ALBERT

Description: Qhar-khetlu dam reservoir is in the central part of Ijrud city of Zanjan province with a reservoir volume of 500000 and a water volume of 900000 cubic meters, covering an area of 6 hectares and containing 3500 hectares of the watershed in order to control seasonal floods, drinking water in the village, strengthening the aquifers of the area and As a water supply in the dry seasons, 120 hectares of agricultural land was planted for irrigation.Study of this water source with the aim of measuring biological and non-biological factors, determination of aquaculture production and Fish release capacity and fishing capacity for optimal use of fishery management in Zanjan province was done in 2006.The results of hydrochemical analysis of the water of Qharkhetlu dam reservoir showed that the minimum and maximum temperature of water ranged from 4.5 to 26 ° C, the pH of the water was 4.7 to 8.8, the dissolved oxygen was 7.7 to 12.2 mg, the total water hardness fluctuation was 154 194 mg / L and electrical conductivity of 272 to 390 micrometers per square centimeter, the water transparency was 25 to 380 centimeters.In this study, six phytoplankton classes with 31 genera and 3 classes of zooplankton with 14 genera were obtained. The abundance of phytoplanktons was counted from 150,000 to 206,000 per liter, and the average chlorophyll a, 1.10 micrograms, was estimated. The frequency of zooplanktons were 32 to 132 per liter, as well as the mean of 544 per square meter of macrobenthos.By comparing of the physical, chemical and biological factors and also the results of previous studies of this water source, the conditions for the introduction of warm water and cold water fishes including silver carp, big head carp, rainbow trout out and native fishes including species of Barbus and Capoeta genera are suitable. Estimation of Qhar-khetlu dam reservoir production is 80 kg / ha and its production capacity is 484 kg per year.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was conducted to determine growth parameters, catch and fishing effort trends, stock assessment and Acceptable Biological Catch (ABC) of Caspian Sea mullets in the Iranian coastal waters of Caspian Sea in the fishing season of 2012-2013. For gathering of data on biometry and catch statistics, 5 mobile working group in the regions of Anzali , Kiashahr , Nowshahr , Babolsar and Torkmen were involved from the start to the end of fishing season.Gathered data Were entered to the computer. For data analysis , common methods were undertaken for estimation of growth parameters , mortality rates , biomass and Maximum Sustainable yield ( MSY ) and Acceptable Biological Catch ( ABC ) as well. . According to the result, the number of beach seines cooperatives was 124 and fishing efforts were 45260 beach seining haul . The catch per unit of effort CPUE) was calculated 37 kg/haul during this fishing season . The total catches of Caspian Sea mullets (including illegal fishing estimated as 2151 mt. Growth parameters of golden gray mullet ( Liza aurata ) were estimated as K=0.12 /yr, L∞ = 59.24 cm, t0 = - 1.31 /yr. Based on catch-at-age data, in the fishing season of 2012-2013 , the total biomass, from the biomass-based cohort analysis were estimated 11321.6 mt. The reference points of F0.1 and F30% were estimated 0.3 /yr . based on these results , the fishing mortality rate in fishing season of 20122013 were very closed to these reference points . In this survey , the Maximum sustainable yield and Acceptable biological catch were estimated as 2207.7 and 1981.4 mt respectively .Results of biometry of leaping gray mullet (Liza saliens) showed that the mean length and weight of this species were 28.8 ± 3.4 cm and 230.5 ± 74.8 g respectively . Based on these results and due to decline of golden gray mullet stocks , it is recommanded to reduce fishing effort and harvest keep to the level of MSY and ABC .The study of spawing condition of golden gray mullet in new situation of this species is also recommanded .

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was conducted to determine growth parameters, catch and fishing effort trends, stock assessment and Acceptable Biological Catch (ABC) of bony fishes in the Iranian coastal waters of Caspian Sea in the years 2010-2011 and 2011-2012. According to the result, the numbers of beach seines were 131 and 128 and their fishing efforts were observed 50184 and 42255 beach seining during 2010-11 and 2011-12, respectively. The catch per unit of effort CPUE) was calculated 182.9 and 205.6 kg/haul during two sampling periods, respectively. The total catches (including illegal fishing) were also obtained 16601.5 mt and 17034.1 mt during 2010-11 and 2011-12, respectively. The highest proportion of catch was belonged to kutum and golden grey mullet (86% and 88%, respectively) in two fishing seasons aforementioned above. Growth parameters of kutum were estimated as K=0.21/yr, L∞ = 60.0 cm, t0 = 0/yr. The Growth parameters were K=0.18/yr, L∞ = 61.1 cm, t0 = -0.14/yr for golden gray mullet and were K=0.12/yr, L∞ = 73.6 cm, t0 = 0.92/yr for common carp. Based on catch-at-age data, in the years 2010-2011 and 2011-2012, the total biomass, from the biomass-based cohort analysis were estimated 41700mt and 34400 mt for kutum and 14600 mt and 14400 mt for golden grey mullet, respectively. The reference points of F0.1 and F35% were 0.41/yr and 0.34/yr for kutum and 0.36/yr and 0.33/yr for golden grey mullet, respectively. Stock enhancement plays an important role in recovery of kutum stocks in the Iranian coastal waters of Caspian Sea. There is a significantly negative correlation between fingerlings released and condition factor (CF) and recruitment and CF. The different trends for fingerlings, recruitments and CF suggest that CF may be partly density-dependent, declining at high population sizes due to intra-specific competition. Therefore, more research should be conducted to determine the desirable level of artificial propagation. Food consumed by fish species, Rutilus frisii kutum, Rutilus rutilus caspicus, Cyprinus carpio, Liza auratus and Liza saliens were included Foraminifera, Porifera, Annelida, Mollusca, Arthropoda, filamentous algae, fish eggs and detritus.The results showed that Rutilusfrisii kutum generally feed on Balanus and Cerastorderma. The main food item for Cyprinuscarpio, Liza auratus and Liza salienswas detritus. Based on available models, the ABCs were estimated as 6600-7400 mt for kutum and 2200-2800 mt for golden grey mullet (with precautionary approach 6600 mt and 2200 mt for kutum and mullet, respectively) in 2011-12. Two species (kutum and golden grey mullet) are vulnerable to environmental factors, and these factors should be considered in the stock assessment and management of the fish. For two species, the ABC with a lower andmore accurate value based onmore information, should be selectedfor the implementation of a precautionary management approach.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Following to introduce Vannamei shrimp (Litopenaeus vannamei) into Iran aquaculture industries by fisheries organization its postlarvae were successfully reared in ponds in Bushehr and Choebdeh in Khuzestan. Due to activity of Shrimp site and importance of input and output water quality, this study was done in 11 stations including: two stations in Bahmanshir river, two station in C4 and C5 irrigation canals, six staions in active farms along C4 cannel (Yonesi, Mosavei and Salman Zadeh), and C5 cannel (Mohamadi, Khairi and Ashraf Por) and one staion in output draing were selected. Sampling were carried out from May2009 befor beginning stocking to harvest time in October 2009. Physico- chemical parameters and plankton sampled biweekly and benthic animals and heavy metals were sampled monthly. Some parameters such as pH and temperature by using portable multy parameters and others. Analyzed with standard methods. Heavy metals were measured by plarography method (797 Vamtro). Plankton and benthos samples were studied only in Bahmanshir station. According to results the maximum values for DO (11.1 ppm) PO4 (1.86 ppm) NO3 (8.4 ppm) and TSS (4992 ppm), pH (8.4) NO2 (0.18 ppm) BOD5 (9.06 ppm) were measured. In comparison to aquaculture water quality standards except for TSS in river stations others are located in allowable range. We didn’t observed any main changes in water quality from river to output drainage. The results of biotic parameters in river stations showed that diatoms were the most group of phytoplanktons. Zooplankton groups were Copepods, Rotifera and Protozoa. Tintinids and Nematoda larvae were the most abundant zooplankton. Benthic animals were included nine crustacean species and two annelid species. Isopods with 52% were the most and ant group.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Menmiopsis leidyi was entered into Caspian Sea from Black Sea and mass population constitutes in the southern Caspian Sea. In this surveys, the relationship between length and wet weight measured and length and weight followed by this equation: n= 384, R^ 2=0.87 w= 0.003 L^ 9005 . The relationship of dry and wet weight calculated, in this surveys, the ratio of dry weight to wet weight was equal to 1.615% in 12 salinity. In vitro, the clearance rate at 12 and 27 C were 52.48 and 107.33 ml/h, respectively, daily ration at above temperatures were 1.98 and 16.65 respectively. Mnemiopsis leidyi can feed Acartia in accordance to 16.5 mg/1gbw (body weight) at 27 C in one day. The average digestive time in 12 C and 27 C were 77.50 min and 36 min respectively. The digestive value in 27 C was 2.5 fold than 12 C . The result indicated that clearance rate, daily ration and digest were increased in high temperature. Stomach content of Mnemiopsis leidyi was shown that this organism utilized from Acartia and Balanus, in addition, stomach content of kilka including two species of zooplankton from the southern Caspian Sea. Stomach contents of clupeonella cultiventris contain more than 54 percent of Acartia and its nauplii. This frequency observed in cluponella engrauliformis and clupeonella grimmi. On basis of zooplankton sampling in the sea, over 90 percentage of zooplankton populations contain Acartia.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: To accomplish the stock assessment that pre-planned for bony-fish resources investigation started by considering two pivotal act. First gathering biometric data and second using catch statistics information for stock analyses. Implementing the research programmes five itinerant groups in Anzali, Keyashahr, Noshahar, Babolsar, Torkaman have been organized during fishing season. The biometric data were supplied in computer that distincted by each fish species and subdivided into age groups. In analyses the samples, Bertalanffy formula used for calculating average length and age, also for growth coefficient. Total mortality rate calculated by using Pauly formula, and the biomass status estimated through Cohort analysis. The catch by beach seiner cooperatives recorded 8630 metric tons, but estimation including. Poacher catch raised the harvest to 15.6 thousand tons. The total catch of Kutum reduced by 1400 tons compared with previous year, but the estimation revealed the biomass of Kutum 18.5 thousand tones, the stock stowed reduction in quantity relative to past years. Harvest exceeding the limit, fishing pressure. And employing higher fishing effort, combining releasing the Kutum seedling with shorter average length in recent years, leaded the shrinkage of biomass of Kutum resources. The Golden Grey mullet catch has been estimated 3437 metric tons, the figure showed 1500 tons increment, in comparison with previous year, nearly 24% of catch was shorter than Lm50% of this species. In Guilan province higher number of sub - size golden mullet captured, this development occured less in Mazandaran and Golestan province. Higher rate of exploitation, reduction of catch in recent years, dominating small size fish in catch composition indicated the population undergoing stress in ecosystem. Thin - lipped grey mullet only comprised 9.2% of the mullet catch - Length - structure of this fish species population formed mainly by young small size fish, the biomass of latter estimated 1100 metric tons. Catch further than maximum sustainable yield, by higher exploitation rate, and gradual diminishing of harvest, represented the resources of this fish species suffering both by high fishing pressure and un - sustainable effort, which ultimately declined the fishery of this fish species. Carp catch and its resources in Anzali region become very low, it is necessary to enhance the stock by Sea-ranching programmes. The carp resources in Gorgan region enjoy better status, but catch practices do not compatible with rule and regulation in Gorgan and Gomeyshan area. The standing stock of Gorgan carp estimated nearly 6000 tons. The information concerning carp resources indicate the stock experiencing pressure and likely the catch will diminish in future. The total catal catch of carp calculated 1900 tons. In recent years the Caspian roach resources are increasing but the bulk of harvest fished illegally and by gill - nets. The total catch of the roach during 1998-1999 estimated 1700 tons. Considering the semi - artificial propagation of roach in Golestan province, if has been concluded the multiplication of this fish species also should be planned by fisheries authorities for Anzali region. It is also advisable catching of this fish species to be regulated soon and selective catch are proposed. The catch of pike - perch during the year of 1997 - 98 jumped to 95 tons, but 90% of catch formed by young fish or sub – standard length size. Almost, all the increment of catch attributed to the releasing of millions of seedlings in the Sea which the plan has been implemented by Iranian Fisheries. Increasing the numbers of released seedlings, with higher average weight Identification of most suitable site for unloading the fries could ensure better survival rate and contribute the enhancement of resources and produce good catch for this desirable fish species. The total catch of Bream hit 18 tons, but most of the catch comprised by young fish with sub - standard size. The present formation of fisheries population of bream are the result of seedling releasing! In the Sea by Iranian Fisheries, since the catch of bream are negligible despite releasing programmes of seedling in a decade which 14million individuals until now, one could conclude the programmes do not contributed effectively to stock rehabilitation. The Caspian Barbus (Barbus brachycephalus) are at the threshold 01 vanishing, at present a few numbers are caught, therefore B.capito appeared in catch composition. The catch of latter species in recent two years are increasing. Total catch during the year of 1998 - 99 estimated 34.5 tons, biomass calculated 93 tons. Caspian vimba are small size fish which beach seiner (mesh size in bosom 30 millimeters) could not capture them ideally, bulk of the catch caught in illegal manner by gill nets. The total catch estimated 154 tons which the present fishing procedures surpassed total allowable catch (136 tons). In recent years the catch of this fish species are increasing. "Shemaya' similar in size with Vimba are caught less by beach seiner, illegal catch are considerable, the total catch in 1998 - 99 estimated 86 tons. The level of harvesting of this fish species are increasing in recent years and its population size become significant relative to last years. The main part of catch concerning Aspius fish species occured in Guilan coastal area, high fishing pressure reduced the population size, including low discharge of water in rivers during spawning period, impact negatively to reproduction. Catch statistic in 1989 showed 128 tons of this fish species are caught but in 1998 - 99 it has been reduced to 6.8 tons. It has been suggested artificial spawning could prevent its fate as endangering species. Caspian salmon catch estimated 78 tons during 1998 - 99, salmon population in Caspian Sea are supported by releasing reared smolts, which in recent years nearly 500 thousands fingerlings released in suitable rivers. After banning the gil nets application in Southern Caspian Sea, the catch of salmon in beach seining are increasing. It is necessary the released smolts in rivers being protected for its safe approach to Caspian Sea. The total catch of herring fish species in 1998 - 99 were nearly 700 tons. The bulk of the catch occur In Guilan fishing area, elimination of gill - nets usage in Southern Caspian Sea contributed the increment of herrings catch in beach seining. The herring resources in Caspian Sea reduced relative to past decades. The catch during 1913 – 1916 ranged between 130 - 160 thousand tons, in Caspian Sea.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Sabzkooh in Ardal and Gandoman region in Charmahal province with annual production of 1300 metric tons of rainbow trout, is one of the most important rivers in the province. The effects of fish farms effluent on the river water quality and the possibilities to develop or limit the existing ones were studied. Flora and fauna of the river including Phyto and zooplankton, macroinvertebrates and fishes were sampled and studied. Moreover some key physico-chemical water quality parameters, concentrations of stable pollutants (heavy metals: Zn, Cu, Fe, Pb, Cd and agricultural poisons (herbicides or pesticides: DDT, Lindane, Alderine and indosulfate) and Coliform contamination were also measured. All phytoplankton genus were of tow taxa, Cianophyta and Chrysophyta and zooplankton fauna belonged to Rotatoria, Protozoa and meroplanktonic chirinomids and nematodes. Four fish species from 3 families were identified of which rainbow trout had the highest relative frequency (94.6%).All the measured heavy metals including Zn, Cu, Fe, Pb, Cd and the agricultural poisons concentrations such as DDT, Lindane, Alderine and indosulfate were lower than the hazardous level suggested for the surface waters. According to the benthic macroinvertebrates populations study, stations at downstream (no. 6 and 7) which received the Chartakhteh and Rudarud farms effluent had least EPT richness and the hilsenhof family level biotic index at this locations was greater than 5.25, classifying them as having organic pollution. Even though measured key physico-chemical parameters such as nutrients (N and P compounds and BOD5) in the receiving stations and effluent water never exceed the maximum permitted range but in downstream stations these factors were very close to the range. One way analyze of variance (P 95%) for TN, TP, No2, NH4, BOD5, pH, PO4 and Ec revealed no significant differences between stations before and just after receiving the effluents, however these parameters in the effluents themselves significantly differ from upstream stations 1,2 and 3 proving relatively lower organic pollution and the potential for constructing new farms or expanding the existed ones in upstream region from Chartagh to Dehnoo. At downstream from Dehnoo to Rudarud and lower parts, dense trout farm effluents in addition with point and non point pollution (municipal, agricultural and other coming run off from the catchments area) had remarkable effects on the river water quality and as a result no farm construction or expansion is recommended. To avoid or reduce the existing farms effects on the river system there should be certainly some remediation actions carried out. Constructing sedimentation ponds before releasing the effluents, obeying the rule of water extracting, preventing fish escape, increasing feeding efficiency and controlling the lateral inlets from catchments area which are potentially pollutant, should be considered to improve the situation and prevent further environmental problems caused by fish farms effluent in these area.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Feeding habits of three dominant species of tuna fishes (Thunnus tonggol, Thunnus albacares, Euthynnus affinis) and dominant species of sardine (Sardinella sindensis) were investigated from December 2006 to November 2007 in the western waters of Oman Sea. Seasonally samples of three species of these tuna and monthly samples of sardine were collected. Feeding studies on 101 longtail tuna (T.tonggol) indicated that the bony fishes were main food of this species (98.3%) and followed by random foods included cephalopods (1.7%) and crustaceans (1.7%). Among the bony fishes, anchovy (66 %) and sardines (25.9 %) were most important than the other fishes. FI and CV for this species were calculated 26.4 and 21.8 respectively. Stomach content analysis of 85 specimens of E.affinis demonstrated that bony fishes were only food for this species (100%). Sardines (49.3%) and anchovy (11.9%) were foremost food items for E.affinis. Moreover FI and CV were calculated 64.7 and 15.3 correspondingly. The stomach of 120 yellowfin tuna (T.albacares) were analyze. Results showed that bony fishes,cephalopods and crustaceans were formed food items of this species .Yellowfin tuna were preferable fed on bony fishes (87.7%) specially sardines(41.2%),flying fish(13.9%)and M.cordyla(10.4%) and followed by cephalopoda (43.8%) specifically Loligo sp.(84.5%) and crustaceans(11.2%) . FI and CV were calculated 38.3 and 25.8.Study on 320 stomachs were determined that zooplankton and phytoplankton formed food of S.sindensis. Zooplankton (crustacean and molluscs) were main food (90%) and phytoplankton (Bacillariophyceae and Dynophyceae) were least food items (10%). Copepoda (crustaceans) with 58% were preferable food and bivalves and after that bivalves (molluscs) with 14%, Bacillariophyceae (8%) and Cyanophyceae (2%) CV and FI were 30.3 and 29.4 respectively.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The research was carried out to investigate phytoplankton, zooplankton and Ichthyoplankton of Khamir, Laft in the western parts of Hormozgan Province and Tiab, Yekshabeh in the eastern parts of it for one year from March 2015 to November 2016. The aim of the study was to achieve seasonal changes of phytoplankton, zooplankton and Ichthyoplankton and compare them among estuaries. In order to achieve this goal, four stations were determined and seasonally sampled. Phytoplankton was taken 2 liter by bottle from 0.5 m below water surface, Zooplankton sampling was done by using standard plankton net with 55 micron mesh size that well equipped with flow meter by horizontal pulling and Bongo Net with 300 micron mesh size used for Ichthyoplankton sampling. During the study, 80 species of phytoplankton were identified, including 53 species, 24 species Dinophyceae, Cyanophycea 2 species and 1 species belonging to Dictyochophyceae. East and West estuaries had the 63% similar percentage of phytoplankton and results showed that 54 Bacillariophyceae genus were common in two regions. The Tiab estuary showed an average 21524±5903 cells/L of phytoplankton high density. Zooplankton was identified with eight phylum. The study of seasonal variations showed that in all seasons crustacean had higher density than other groups. Four copepods orders were identified which the calanoid had higher density and distribution in compare to others. 19 families of the larvae were identified and 69/99% similarity was also observed between estuaries of two region. Glupeidae, Gobiidae, Engraulidae and Scianidae families were abundant than other families. Shannon-Wiener, Maraglef and Evenness biological indices were found higher in west than the East estuaries. The results showed values were the highest in laft estuary, respectively H'= 3/22, d=7/11 and J'=0/72. The lowest biological indices in Tiab estuary, respectively H'= 2/233, d= 4/109 and J'= 0/597. The estuaries in the West had more diversity and eveness. The highest and lowest of biological indices were obtained (d= 5/948 and H= 2/759) and (d=2/825, H=0/830 and J=0/249) in the winter and summer, respectively.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The shrimp farming success in the future will greatly depend upon increasing supplies of healthy and high quality seed for stocking ponds. The limited and inconsistent availability of wild shrimp postlarvae together with an urgent need of establishing selective breeding programs, increased the interest in captive broods of penaeid. Many investigations have been carried out on several shrimp species world-wide. This study have been conducted on 2 shrimp groups since September (Mehr) to July (Tir) 1999 in Bandar-e-Imam southwest Iran. The wild group (SPB) prepared from Jask area and the pond group (POB) prepared from artificial ponds upon harvesting them as marketable size have been investigated. 2 groups were exposed to natural diets consisting of squid and artemia biomass in same conditions using 12 m3 concrete tanks. Stocking density was 2 piece/m2 (1F:1M). Half part of the pond bottom covered by fine sand to reduce the stress where the other part has been used for feeding. Daily ration given in 3 times by satiation method. Also reproductive performance of wild gravid brooders (WLB) were recorded as a control group. 2 examined groups well grown and around 50% of the SPM and around 30% of POB females successfully ripened a produced eggs and nauplii where almost all males of both groups were matured. Data showed fecundity is highly correlated to the TL and W of the brooders by positive trend. Considering the TL, W, Fecundity and nauplii production the WLB brooders are significantly (P=0.05) higher than 2 other groups, while the SPM broods are significantly (P=0.05) higher in hatchability. Meanwhile the survival rate from nauplii to postlarvae stage was around 30% for SMP brooders. On the other hand the growth parameters (TL, W) of the marketable size of the shrimps produced from SMP brooders were significantly (P=0.05) higher than those produced from WLB group. Since the fecundity is improvable by increasing the brood size thus the data suggest the sup.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The aims of this project was to inform and aware about the red tide condition before entering the algal bloomer in water resources to the hatcheries and farmed shrimp complexes in Bushehr province coastal. Field investigation and sampling have been carried out in the southern of the input water channels of Mond, Delvar and Helleh farmed shrimp complexes, which are located along the coastal of Bushehr Province, from April to December 2011 .The physic-chemical parameters such as pH, salinity and water temperature and also meteorological conditions were measured and recorded on the field. The water sampling has been lunched for determination of nutrients and chlorophyll - a, phyto- and zoo- planktons. No Cochlodinium.sp outbreaks have been detected in the studied area, during the study. The only bloom which reported by a fisherman, was outbreak in offshore of Bushehr province in Khoure Khan on 13th September 2011. The sample which transferred to the Iranian National Shrimp Research Institute was included Alexandrium.sp and its density was 2 million cells per liter. The identified phytoplanktons were belonged to three order of Bacillariophyceae (52.6%) with average density of 10778 cells per liter, Dinophyceae (37.7%) with density of 7731 cells per liter and Cyanophyceae (9.7%) with density of 1980 cells. 12 genera belonged to Dinophyceae , 25 genera of Bacillariophyceae and two genera of Cyanophyceae were observed during the study. The highest density of phytoplankton was recorded in Helleh station by 18374 cells per liter. The maximum density of phytoplankton was at Delvar station by 141120 cells per liter in December. The highest density of the phytoplanktons was belonged to Dinophyceae by 126000 by cells per liter of which the Alexandrium.sp had the density of 124500 cells per liter in August 2011. From the Dinophyceae the Alexandrium.sp with mean density of 20345 cells per liter, Ornithocercus 920 cells and Prorocentrum.sp 820 cells were the predominant species. The identified Zooplankton in were belonged to 8 branches and 19 groups. The highest density of zooplankton was recorded in Helleh station by 1194 no. per liter. Nauplii were the dominant zooplankton groups with an average density of 136.4 no. per liter, Tintinnids 98.7, Cyclopoida 60.8, Calanoida 35.7 and Harpacticoids 14.5 no. per liter . The average of water and air temperature was recorded 29.4 °C and 28.3 °C, respectively. Average of salinity was 41.2 and pH was 8.46. The average of depth in all stations was 5.7 m. The mean concentrations of silicate, nitrate, nitrite, ammonia and total phosphate were 1.99, 0.03, 0.009, 0.14 0.15 ppm, respectively and the average of chlorophyll - a was 0.94 mg.m-3.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This research was done to study on communities' strucure of benthic animals' growth on artifitial reefs, constructed in Hendijan coastal waters in khozestan in Nort west Persian Gulf. The seasonal sampels of attached organisms were collected from spring to winter during 2010 year study.One station (D) in older and three stations (A, B, C) in newer reef site were selected.Random sampling was carriedout by using quadrat (25×25) via diving. During survey, the number of 59 species of attached animals belong to 13 animal groups, including, 9 species of cnidarian, 8 species of spoges, 7 species of Gastropoda, 8 species of Bivalve, 4 species of polychaet and 17 species of Crastacean were identified. In studied artifitial reef apoint of biomass, softcoral were dominant group which include 92% of total biota, and the species Plumarella sp. is the dominant species. However, apoint of abundance the species pisidia sp. from anomura crabs was the most abundant species especially in station A and D. Different kind of Cnidarian such as Dendronephthya sp., Sarcophyton sp. And Lobophyllia sp. was observed in station D for the first time. The polychates, Mollusk and some of crustacean and Echinodermata species were observed in lower abundance in comparision with previous studies. This results show that communities have been changed along time. According to MDS analysis, based on Bray-Curtis similarity, different stations presented seasonal variation based on identified species-biomass. Clustering analysis based on mean biomass indiffernt seasons explained that. Station D in 55%, station B in 75% and staton A and C in 80% similarity were Seperated. According to obtained results, there were not signifidant differences between station that can be caused by similarity in structural characteristics such as bottom slope and age of reefs. The mean abundance in spring was significantly high than other seasons. Which can be caused due to bioticfactos such as life cycle and reproduction season? In this research, fish communities accord to recorded information by visual consus and fisheries Traps arund the reefs, hare been increasing. In present study with increasing biomass in the biotic communities on artificial reefs enhancement of fish stock most be expected. These substrates can be reduced the pressure on destructed which is the opportunity for rehabilitation. In present study with increasing biomass in the biotic communities on artificial reefs enhancement of fish stock most be expected. These substrates can be reduced the pressure on destructed which is the opportunity for rehabilitation. The most frequent and abundant fish species was Epinephelus sp.. This species was presented in all stations and seasons. The other abundant fish species were Scolopsis sp.,Epinephelus coioides, Diplodus sargus and Neopomacentrue sp..

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This investigation conducted for evaluation Silo (Cylindrical) Fish Tanks as an applicable method for aquaculture of Rainbow trout (Oncorhynchus mykiss). Current research was designed in two practical phases as accidental experiments through 3 treatments and repeats of which stocked by three Rainbow trout (375 gr) densities as 75, 100 and 125 fish/m3 in 9 silo fish tanks (2 m3). For better understandings of the silo performance method, concrete circular fish tanks (similar volume) considered as controls and stocked as similar fish densities as silo tanks. The duration of the first phase of experiment was 150 days. The second phase of the experiment was determined for evaluating two proposed silo type (Inlet and outlet in bottom side / Inlet from bottom and outlet in upper side). In this stage, proposed silos (stocked by fish of 294 gr weigh) tested for rearing trout for 30 days. Water supplied from two surface wells after some aeration operations. Stocked fish were fed by pellets made by Fish Feed Chineh Company (Ltd) in Iran. Feeding operation conducted according to the recognized manuals by consideration of water temperature, fish weight and biomass. Meanwhile, biometry operation conducted in 10 days intervals while fish were anaesthetized. In addition, water quality was determined by daily measurements. According to the results of the first phase of experiment, there were significant variations on Growth rate, survival rate, FCR, FCE and SGR through the cultured organisms in silo tanks compared to the circular tanks. Meanwhile, according the results of an economic study on this survey, the fish culture in silo tanks showed significant economical and profitable in compare to controls. In additions, the second phase of experiment showed better aeration conditions in silo tanks when inlet water supply from bottom side and outlet located in upper side. Because of the fine distribution of fish in silo tanks and more usage of depth by this method, fish culture would be an applicable and profitable technique in narrow lands and slopes through the mountains area. The maximum stocking rate recorded more than 100 Kg fish/m3 in silo tanks.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Mnemiopsis leidyi is one the species of comb-jelly. It belongs to the Ctenophore phylum and lobate order. Mnemiopsis leidyi first appear in the Black Sea in 1980s and reached to the biomass levels up to 1.5-2 kg m2 in the summer of 1989. This species is food rival of pelagic fish. It has been reported that the ctenophore caused the dramatic decrease of zooplankton and pelagic fish stock in the Black Sea. In this study, sampling on Mnemiopsis leidyi, zooplankton and phytoplankton started from July to December 2002 from a total of 2 stations located Anzali and Khazarabad by METU net in the Iranian Coasts of the Caspian Sea. Experimental studies on Mnemiopsis have indicated that Mnemiopsis begins to produce eggs in the Caspian Sea, when it reaches length about 15 mm. Although eggs were obtained even from specimen with 12 mm length and weight of 0.5 g. The most abundant size of reproducing Mnemiopsis was 20-30 mm in the Caspian Sea. Average fecundity of M.leidyi in the Caspian Sea was 1174±741 eggs/day with maximum 2824 eggs/day for specimens with length group of 30-39 mm and the weight about 2.0-2.7 g. Percentage of hatched eggs was not high in experiments with M.leidyi the range from 9 to 92 % after 24 hours. The maximum produce egg of M.leidyi measured with mean 845±733 eggs/day in Salinity of 11 ppt and the minimum egg recorded with mean 2 eggs/day in salinity of 4 ppt. The results showed that the biomass of M.leidyi had some fluctuation in different months and its maximum biomass was recorded in August with a figure of 384±156 g.m2 and the minimum biomass was observed in December with a figure of 87±46 g.m2. The gut contents of Mnemiopsis leidyi showed a wide variety of prey including 84 % of zooplanktons and 16% of Phytoplanktons. The most abundance of intaked foods was Acartia (belong to Copepoda) with 34 % and the least was podon polyphemoides (belongs to Cladocera) with 0.74 %. Also 3.0 % of fish eggs and 4.2 % of Lamllibrachia were found among stomach contents. The young specimen (5〈 mm) consumed more zooplanktons and phytoplanktons comparing to adult ones. Copepoda was dominant zooplankton in the Iranian coasts of the Caspian Sea. Fecundity of Mnemiopsis showed correlation to the length and wet weight in the Caspian Sea and reproduction of M.leidyi was done small size in comparing with other area in the Caspian Sea. Salinity, water temperature and food availability is the most important factor in producing eggs in M.leidyi. It seems, that Mnemiopsis leidyi feeding has been one of the most important factor in declining zooplankton populations and Clupeonella stocks.

Description: Iranian Fisheries Science Research Institute

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Description: Biomass estimation of fishes were done by depletion method in Shadegan Wetland in 2011-12. Fishing effort and landing catch amount per unit effort was done via random oversea in fixed landing area monthly. Fishermen and catch statistics were obtained from census. Total catch was calculated from multiplication of effort and average catch. Fishes biological characteristics survey indicated that Golden barb (Barbus luteus) and Berzem ( Barbus pectoralis ) has maximum (62 kg/ha) and minimum (4 kg/ha) biomass respectively. Maximum and Minimum biomass was in spring (380 kg/ha) and in winter (58 kg/ha) respectively and mean biomass was estimated 249 kg/ha in whole area during one year. Number of fishermen were about 1317 and maximum fishing effort was in April, May and June. Total fish landing was 4300 tons per year in which 1119 tons was calculated in April. Large scaled barb ( Barbus grypus) and Abu mullet (liza abu) had maximum and minimum mean length and weight. The range length of most of fishes was low and their spawning season was in winter and spring. Length- weight relationship indicates their isometric growth. Despite of 45% decrease of number of fisherman to previous time (2008), catch effort and exploitation was increased (20%). Regarding fish living area (70000 ha), total biomass was 17430 tons.

Description: Iranian Fisheries Science Research Institute

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Description: Regarding to monitor of demersal resources in the Persian Gulf and Oman Sea, and also biomass and CPUA estimation of them, eleven research cruises were carried out by using R/V Ferdows-1 equipped with bottom trawl, covering the area from 49º 00´ E in the west (borderline with Kuwait) to 61º 25´ E in the east (borderline with Pakistan) from 2009 to 2011. The study area was stratified into 17 strata (A to Q) of which 10 strata (A to J) were in the Persian Gulf and 7 strata (K to Q) were in the Oman Sea, covering the depths of 10-50 m in the Persian Gulf and 10-100 m in the Oman Sea. A total of 316 stations were randomly selected and the biomass and CPUA were estimated by swept area method. In 2009, due to the bloom of jellyfish, there was some problem for sampling and therefore made some bias in our estimation. Therefore, the biomass of jellyfish was excluded from all calculations. The comparison between two regions indicated that the percentage of density of demersal fishes in the Persian Gulf during years 2009, 2010 and 2011 were 1.5, 3.7 and 1.7 times more than the Oman Sea and totally 60-80% of total biomass was found for the Persian Gulf. Also a comparison among 17 strata the highest biomass was found for K region (Sirik to Jask) in the Oman Sea in 2009 & 2011; and C & D regions (Genaveh to Dayyer) in 2010 in the Persian Gulf. The same comparison was done for CPUA of commercial, non-commercial and total in both water bodies and it was found that in years 2009 and 2011 the regions of L (Jask to Meidani) and K (Sirik to Jask) in the Oman ; and 2010 the G region (Mogham to Farour) in the Persian Gulf had the highest value of this parameter. It can be concluded that the north-west of the Oman Sea has the best condition of biomass and CPUA of commercial and non-commercial demersal fishes; and on the contrary the low values were estimated for A region (north-west of the Persian Gulf) and P region (Konarak to Ramin) in the Oman Sea. With review the mean CPUA in defferent depth layers for years 2009, 2010 and 2011, it was concluded that with increasing the depth, the mean CPUA is decreased and the lowest CPUA belongs to depths of 50-100 m. The comparison between commercial and non-commercial groups in both ecosystems, it concluded that the density of commercial species were higher than non-commercial ones; and for years 2009, 2010 and 2011 the commercial species consist of 52.2, 57.1 and 59.7 % of total biomass. In all years the Persian Gulf indicated higher values than the Oman Sea. The most abundant fishes were Rays, Catfishes, Grunts, Japanese threadfin bream, Carangids, Hair tail, Barracuda and Lizardfish for both Persian Gulf and Oman Sea.

Description: Iranian Fisheries Science Research Institute

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Description: Aquatic animals possess specific biological characteristics and lifecycle. Without knowing about their biology and complete lifecycle, planning about their conservation can not be effective. Following the previous studies on fish larvae in Khuzestan coastal waters this study was done to determination catch composition and density of juvenile fishes in Khuzestan coastal waters during 2007 to 2008. Studied area included two main fisheries ground, Lifeh-Busafe in west and Bahrekan in east coasts. Monthly random sampling was carried out by using shrimp trawl net with Akhtar vessel. Juvenile fish's means the fishes that completed their larval cycle and are look like their parents but have not been matured yet. The catch mean, biomass, CPUA and the stock size of different species were estimated by using Swept Area Method. Totally 101485 caught fishes included 38 families and 63 species. The most abundant trawled fishes were Thryssa vitriostris Leiognathus bindus Ilisha melastoma Penahia macrophthalmus and Johnius belangerii .These five species contain about 80 %, the species Arius dussumieri and Cynoglossus arel 4.5% and 3.2 % respectively and the others 12% of total caught fishes. In the east coasts the species L. bindus I. melastoma T. vitriostris P. macrophthalmus and in the west coasts the species P. macrophthalmus T. vitriostris J. belangerii and I.melastoma were the most abundant. Among 63 identified fish species , juvenile fishes of 23 species were observed which contain 26.4 % of total caught fishes .the fishes Arius dussumieri and Acantopagrus latus 100%, Liza subviridis, Leiognathus lineolatus and Triacantuhus biaculeatus more than 80 % and Pomadasys stridens Lagocephalus inermis Saurida tumbil and Thryssa vitrirostris more than 50 % were observed as juvenile stage. The most abundant juvenile fishes were T. vitrirostris L. bindus and Arius dussumieri respectively. The maximum (1852 kg/km2) and the minimum (165 kg/km2) values of CPUA were estimated in west coasts in July and December respectively. The maximum (2677 kg/km2) and the minimum (153 kg/km2) values of CPUA were estimated in east coasts in June and August respectively. The biomass showed a distinct peak in June and July in east and west coasts respectively. The highest diversity index in east (2/22) and west (2.36) coasts were obtained in July. In present study the number of identified fishes is more than previous studies. Juvenile fishes spend their sensitive period of lifecycle in Khuzestan coastal waters. After growing in late spring, fish larvae enter to the juvenile stage and select this productive area as nursery ground. Increasing of juvenile fishes in July is accordance with their reproduction season in studied area. The east coasts are deeper than the west and there are some differences in hydrological characteristics due to discharging of the rivers Bahmanshir and Arvandrood in west coasts. The peaks of abundance in east and west coasts were observed with a clear time interval. The higher CPUA in east coasts can be caused due to gradual migration of juvenile fishes from west to east during cold season.

Description: Iranian Fisheries Science Research Institute

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Description: This study was carried out in North of Persian Gulf from 2001 to 2002. Sampling was done in two transect (6 stations) in different depth in Khuzestan coastal waters. Some environmental parameters such as temperature, salinity, pH, DO, density, EC and chlorophyll a by CTD instrument and also Nutrient were measured. Phytoplankton was collected with Niskin sampler from 4 layers 0.5, 20, 50 meter and 2 meter above the bottom. Zooplankton and benthic fauna sampled by Pump and Peterson grab respectively. Physical and chemical parameters were showed little fluctuation during the year. The highest variation ranges were observed in: temperature (17.7-33.8), pH (5.3 - 7.2), DO mg/lit (2.9 -7.5), turbidity (3.8-16.3), salinity (39.4-40.9). The most frequent phytoplankton was observed in classes of: Bacilariophyceae (62%), Cyanophyceae (29%), and Dinophyceae (16%).The most frequent genus of each phytoplankton group were Rhizosolenia, Nitzschia, and Pluerosigma. Occurrence of phytoplankton decreased from surface water to depth layers and then increased near the bottom. The highest diversity and evenness indexes were in spring, summer and winter respectively. The most abundant of zooplankton were founded 5 groups included: Crustacean, moullsca and polycheata larvae, protozoa and some a few Chaetognaths. The most frequent groups of zooplankton were Copepod (62.9%); Moullsca larvae (26.1 %) and the most abundant of copepod genus were: paracalanus, Oncea, Oithona, Microsetella. Zooplankton in off shore stations were more than near shore stations. The most abundant of benthic groups were: Amphipoda (25%), Bivalve (18%), and polycheata (17%). The type of sediment in all stations was silt - clay. Max. and Min. anmount organic matter was 47.18% and 15.3% respectively.

Description: Iranian Fisheries Science Research Institute

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Description: The present project in related to survey of factors and hydrology and hydrochemical features (water temperature, dissolve oxygen saturation, pH, clearance, salinity, nitrogen, phosphorus and silicon) hydrobiology (zooplankton, phytoplankton, macrobenthos) and survey of bio environment pollution (oil, heavy metal, detergent) executed in lower 10m in different water larger in southern Caspian Sea in 2002-2003. For sampling 8 lines number were vertical on coast that selected from Astra in west to Gomishan in east in southern Caspian Sea basin. The result indicated the average physical factors such as pH were 8.11 and salinity12.12 ppt ,and disolve oxygen6.7 mg/l. Average chemical factors such as NO2 , NO3 and NH4 were 1.2 µg/l, 25.7 µg/l, 13 µg/l respectively.Total nitogen and organic nitrogen and inorganic nitrogen were 690.2 µg/l , 667.6 µg/l , 41.6 µg/l. Average silicat were recrded 266.35 µg/l . Total Phosphorus was observed 37.35 µg/l and average of organic Phosphorus concentration was and 20.25 µg/l .Average of Total organic matter (T.O.M) was 4.98% maximum amount were observed in Lisar and minimum in Nooshahr . Concentration of heavy metal during sampling were respectively ,Fe〉Mn〉Zn〉Cr〉Ph〉Co〉Cd〉Cu. Maximum concentration of Fe were determined in winter in Nooshahr and Babolsar respectively 13/3 µg/l 17/1 µg/l. In many stations and different Season, the amount of heavy meta were lower standard of in marine water. The concentration of oil hydrocarborate ( PAHs) in autumn was 0/13 ppb and in winter 0/12 ppb. The amount of ( PAHs) in Southern Caspian Sea were Lower than other parts of Caspian Sea. The average of detergent concentration ( LAS) was 0/036 µg/l that was two fold higher than determined in 2001. Total 107 species of phytoplankton belong to 5 phylum were identified. The numbers of species of phytoplankton groups were respectively, chrysophyta (42 species), cyanophyta (17 species), pyruphyta (17 species), chlorophyta (21 species) and euglenophyta (9 species). The maximum diversity of phytoplankton observed in summer and minimum in autumn. High diversity of chrysophta and cyanophyta observed in summer and phyrophyta and chrlophyta in spring. The composition of phytoplanhkton groups were respectively, chrysophyta (70%), phyrophyta (9%) and chlorophyta (7%) and euglonophyta (1%). Maximum density of phytoplankton was observed in autumn and minimum in winter. Total 19 species of Zooplankton were identified. Maximum diversity was observed in summer and minimum in winter. Zooplankton changes during sampling, showed amount of density of zooplankton in 5m were more than 10 m depths. Total (17 species macrobenthos were identified. The composition of macrobenthos groups were respectively , Annalida (92/7% ) , Bivalvia (2/7%) gumarida (108%) cumacea ( 1/5%) , Balanidae 103% . max . density were observed in Astara and min . in Sefied roud Average of density were 1218 0/851 ind /m2 and biomass 14 15 g/m2 High density were recorded in autumn and low density in winter . Correlation of phytoplankton and zooplankton with physicochemical parameter and also relation between total organic matter and sediment grain size were calculated.Ecological indicies (simpson diversity evenns diversity and shanoon-wiever diversity) were calculated for macrobenthos. Data were shown impact of cetenephora (Mnenemiopsis leidyi) on zooplankton and phytoplankton and macrobenthos density.

Description: Iranian Fisheries Science Research Institute

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Description: This study was carried out in continuation of previous studies on artificial reefs monitoring in Khozestan coastal waters. The main purpose was the zoo species composition on and around the artificial reefs. Sampling was done from May 2012 to April 2013, from 4 stations in artificial reefs area. Reef structures were sampled by scuba diving. Physical and chemical parameters were measured and water quality status was determined by using WQS index. Zooplankton and macrozooplankton communities were sampled by 100 and 300 micrometer mesh size nets respectively. Benthic animal's samples from sediments around of the reefs body were collected by Ekman grab. Sediment characters, TOM and grain size were analyzed by using ignition loss and size series sieves methods respectively. Secondary production of macrobenthic animals based on dominant species length classes was estimated. Ichthyological information recorded by diver (census and video recording) and Gargoor traps were used for fishing effort calculation .Except for nitrite parameter (p〈0.05) in different stations and silica parameters (p〈0.05) in different months, other parameters were not shown significant differences in studied stations and months. The mean of zooplankton density was (914±52) N/m3 and the Copepoda species were the most abundant group (235 ±10) N/m3.Anosim analysis showed no significant differences in reefs specie composition. Different Crustacean groups were included more than 82 percent of macrozooplanktons communities. Among macrozooplankons, the mean density of decapoda, branchiopoda and copepoda were 302, 296 and 191.5 N/m3 respectively. The mean density of macrobenthic animals was 418±90.26 N/m2 and mollusk, crustacean and polychaets were the most abundant benthic animals respectively. During the study period, total macrobenthos biomass 11.37 g-wet/m2 and its mean value 2.84 g -wet /m2, were estimated. Annual production for polychaets and crustacean groups 154g-wet/m2 and 182 g-wet/m2 were estimated respectively. Annual production of total macrobenthic animals was about 675 g-wet/m2/y. According to sediment analysis, the range of silt-clay (8.7-95.6)% and seasonal mean TOM (4.47-13.25)% were calculated in studied stations. According to attached organisms biomass (wet weight), Cnidarian Anthozoa class with (88)% was the most abundant and then sponge (10)%, Cnidarian Hydrozoan class and arthropoda each one with 1% were included total attached organisms. Due to high biomass of Anthozoa species the most abundant mean was observed in spring season. The Malacostraca group especially Crustacean (72)% was the main mobile animals on reef bodies and then Echinodermata (Ophiurida and marine Orchids) (18)%, Mollusca (Bivalves and Gastropods) (4)% and Polychaets (3)% were the main mobile organisms. The range of Shannon diversity index was (3.22-3.46) and (2.44-3.38) in studied stations and months respectively.Totaly in studied area, the number 15 fishes species were observed and Sparidae family with 3 species were the diverse fish family.The fish Hamour (Epinephelus coiodes,Seranidae) (87)% was presented in all studied months and stations. After Hamour the Neopomacentrue sindensis and Diplodus sargus Kotschyi were the most abundant fishes. The maximum and the minimum of hamour catch per unit effort were in reef B in spring and reef C in autumn respectively .Data comparing showed that except for nitrite the other physical and chemical parameters were observed in the same range by 2005-2007 study. According to obtained results, Zoo communities in different part of ecosystem showed greater diversity than to past years and in comparing to mudflat coastal waters in Khozestan waters, new ecosystem has been created in the region. High diversity of different animal groups that were disperses in water column in early phases of its life and need to settlement to substrate to continuing the life were observed in area. Attached animals plays an important role in biological and ecological characters in the coastal area.

Description: Iranian Fisheries Science Research Institute

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Description: In order to the physical and chemical factors, planktons identification, determination of Chlorophylla and primary production in lake on study wad conducted, behind the Halilrud dam in Jiroft city. For this purpose 5 station selected and sampling was performed seasonally. Compersion of physical, chemical factors and planktons were done by duncan multiple test range. Studied factors had the suitable value for fish culture. In classes of Chrysophyceae, Bacillariophyceae and, Chlorophyceae had the most frequency respectively. Totally 49 phytoplanktons genus were identified which 18, 14,8,5 and 3 genus were related to Chlorophy ceae, Bacillariophyceae, Cyanophyceae, Dinophyceae and Chrysophyceae, genus respectively. Nitzchia and Navicula in Bacillariophyceae, Chlorococcum, Pediastrum, Staurastrum and Tetradron in Chlorophyceae, Spirulina, Chroococcus, Phormidium in Cyanophyceae and Dinobryon in Chrysophyceae had the most frequency. From Various group of zooplankton, Copepoda, Naplius, Cladocera, Rotifera (Brachinus, Keretella), Trichuridae were identified in winter season and Rotifera was the most of all. Chlorophylla had not significant difference in 9 seasons but it had significan difference in 5 depthes. Increasing in depth causes to decrease chlirophyla. The most chlorophylla was in 0.5m depth (4.7 mg/m3 ) and the least chlorophyllla was in 20m depth(0.82mg/m3) primary production in lake was calculated by chlorophylla equal to 154 kg/ha/year.

Description: Iranian Fisheries Science Research Institute

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Description: The Caspian Sea is the largest lake, both by its area and volume. Zooplankton are very important in the food web since many animals eat them.The Sampling was done in 4 transacts in Anzali, Tonekaboun, Noushahr and Amirabad at 3 different depths including 5, 10 and 20 m. Sampling was carried out in four seasons of spring, summer, autumn and winter in 2013. The annual changes of zooplankton was between 392±113 ind./ m3 in autumn (Amirabad) to 8065±11735 ind./ m3 in winter (Amirabad). The lowest density of zooplankton in the spring was 2207 ind./ m3 in Anzali. The density of zooplankton in Tonekabon and Amirabad was 2.0 and 2.8 fold more than other transects respectively. The results showed that the abundance of zooplankton in summer was between 1964±470 ind./ m3 (Amirabad) to 5706±6088 ind./ m3 (Tonekabon). The biomass was 30.02, 52.22, 22.98 and 18.31 in Anzali, Tonekabon, noshahr and Amirabad respectively. The abundance of zooplankton in the autumn reached the lowest value. The lowest value was 392 ±113 ind./ m3 and 3.71± 0.19 mg/ m3 (Amirabad) and highest value was 2280 ±1435 ind./ m3 and 20.23 ± 14.50 5mg/ m3 (Anzali). The highest density was observed in Amirabad (8065 ind./ m3 ) and Anzali (8061 ind./ m3 ) in winter. The aim of this study was diversity, distribution, density and biomass of zooplankton in the southern of Caspian Sea.

Description: Iranian Fisheries Science Research Institute

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Description: This study was conducted from january. 2002 to April .2004. During this survey four research cruises were carried out on aquatic animals. This survey was based on cruise and area which are as follow: 1. Identification of species _ Palaemon adspersus _ Palaemon elegans 2. Length and weight frequencies 3. Length and weight Relationships 4. Distribution according Catch Per Unit Area (CPUA) separately for each sampling station. 5. Sex ratio of P. adspersus 6.Biomass P. adspersus: Following results for p. adspersus was obtained in The Gorgan bay: Min. and Max. of carapace length (CL) in 1st cruise were : 11.50 and 18.40 mm ( female ) 9.60 And 15.70 mm (male) respectively. CL mean was 13.99 ±1.51 and 13.61 ± 1.37 mm for female and male respectively. Min. and Max. of total weight (TW) was 0.7 and 3 gr. (female ), 0.2 and 1.80 gr. (male) which their mean was 1.36 ±0.51 and 1.23±0.32 for female and male and female respectively. Min. and Max. of CL in 2nd cruise were: 8.70 and 18.70mm ( female),8.70 and 15.60mm(male)which the mean were 13.89±2.4 and 11.59±1.62mm for females and males respectively. Min. and Max. of TW in Second cruise were 0.6 and 3.80 gr (female), 0.5 and 2.70 gr (male) which the mean were:2.13±0.7 and 1.22 ±0.43 for females and males respectively. L/W relationship equations were as follow in the 1st and 2nd cruises: 1st cruise: TW = 0.0007CL ^2.8418, R²= 0.7623, (female) TW=0.0014CL^2.5872, R²=5402, (male) 2nd cruise: TW=0.0066 CL^2.1847, R²=0.8146, (female) TW= 0.0044 CL^2.2859, R²=0.8149, (male) Sex ratio (M/F) in the 1st and 2nd cruises were 1.18:1 and 0.44:1Respectively. Distribution in the 1 st cruise obtained in the East, eastern south near coasts (less than 1 n mile) and in the 2nd cruise obtained in the North east, North and South parts near coasts. In the South east of the Caspian Sea: Min. and Max. CL were 5.6mm (1st cruise) and 17.50mm (3rd and 4th cruises). L/W relationship equations were: TW = 0.0019 CL^2.6037, R²=0.7814 (3rd cruise) And TW = O.0023lCL^2.5475, R²=0.8804. In general numbers of shrimps were less in the 1st and 2nd cruises. Sex ratio (M/F) obtained 1:1, 1:1, 0.52:1, and 1.02: 1 respectively from 1st to 4th cruises. Shrimps were present in all depths however, when the temperature dropped this species moved toward deep water. P.elegans: CPUA and Biomass were estimated . The biomass was 46.64 Kg and 97.62 Kg in TheGorgan Bay and south east of The Caspian Sea respectively . The number of P.elegans was very few both in the Gorgan Bay and the South east of the Caspian Sea. The review of The P.elegans is described at The very end of the present research report.

Description: Iranian Fisheries Science Research Institute

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Description: This study was carried out in the North of Oman Sea in parts of Iranian waters during pre-monsoon and post monsoon seasons between 2007 and 2009. Number of 10 transects were chosen from coastal to maximum 50 meter depth. Cruise was done with Fredous ship and Rosette bottle multi watersampler was used for sampling. A phytoplankton community in the North of Oman Sea included in 204 species and divided in six taxonomic divisions: Bacillariophyceae (89 species), Dinophyceae (105species), Cyanophyceae (6species), Dicthyochophyceae (2species), Euglenaphyceae and silicoflagellate each (1species) respectively. Density decreased in most transects from inshore toward offshore waters and maximum density was in surface layear.Significant differences between each transects were found. Dinophyceae and Bacillariophyceae were dominant in pre-monsoon and post-monsoon respectively throughout two years. Important genuses of diatoms are Rhizosolenia, Chaetoceros, Pleurosigma, Coscinodiscus, Gyrosigma, Nitzscha, Navicula, and Leptocylindrus. And also there were Dinophyceae like: Scrippsiella, Pyrophacus, Gymnodinium, Pyrodinium, Prorocentrum, Cochlodinium, and Noctiluca. Phytoplankton density in the post-monsoon were recorded higher than pre-monsoon, furthermore phytoplankton density in 2009 was more than 2007. Cochlodinium polykrikoides density increased in 2009 especially in the pre-monsoon then dropped to post-monsoon season. Zooplankton population in this study is characterized by 8 phylum, 8 classes, 15 orders, 35 families and 78 genuses. Copepoda was the most abundant group of zooplankton and included in 4 orders of Cyclopoida, Calanoida, Poecilostomatoid and Harpacticoida. The static result showed significance among different transects layers and lines. In this study, 31 ichthyoplankton families with different density and distribution were recorded. In the pre-monsoon eight families was identified and Scainidaea family had the highest density and also in postmonsoon 6 families was classified in which scainidae was dominant family. In pre-monsoon 2009, we found 8 families that Pomacentridae family had higher density; Hemiramophidae was in the second position and followed by Clupeidae. In post-monsoon season density and diversity were increased and 23 families were recorded. Myctophidae family was the most abundant. The highest frequency there was other important families like Engraulidae, Synodontidae, Scainidae, and Leiognathidae in this period. Result of this study indicated that the monsoon was important and effect on abundance, distribution and species composition of plankton.

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Description: The alarming rate of population growth has increased the demand for food production in third-world countries leading to a yawning gap in demand and supply. This has led to an increase in the number of hungry and chronically malnourished people. This situation has created a demand for the formulation of innovative and alternative proteinaceous food sources. Single cell protein production is a major step in this direction. SCP is the protein extracted from cultivated microbial biomass. Algae, fungi and bacteria are the chief sources of microbial protein that can be utilized as SCP. Produced proteins from these microbes have various nutrition values. SCP is the manufacture of cell mass using microorganisms by culturing on available agriculture, industrial wastes and fisheries by products. Fish wastes due to high protein are the most important substrates for SCP production. In this study, SCP production was done from Silver carp and tuna fish wastes (head, tail and vise versa) and cooked water of canned tuna factories. The used microbes were six genus and species of yeasts include Candida utilis, Saccharomyces cereviceae, Rhodotorula, Khyveromyces marxians, Zygosaccharomyces rouxii and Bacillus subtilis and B.licheniformis. The examination was done in bench scale and CSTR bioreactor (Continuous Stirred Tank Reactor). The effects of various parameters such as pH, temperature, time, supplemented substrates, method of inoculation of microbes, rpm were evaluated. Changes of microbial growth and protein contents were tested by using Optical Density (OD) and Makrokjeldal methods respectively. In end of examination, produced protein were extracted and lyophilized. The results showed that protein percentage in bacterial protein was than yeast protein but wet percentage in bacterial protein was low. Production value produced from tuna fish wastes was higher than (30-45 g/l) to Silver carp wastes (25-29 g/l) and cooked water (10-15 g/l). By adding supplemented substrates, production value has been increased. Candida utilis, in comparison other yeasts, has high activation. B.licheniformis has also had more activation than Bacillus subtilis. The results of the effect some parameters on fermentation showed that yeasts and Bacillus in pH= 5.4 and 32oC and pH=6.9 and 35oC were better than growth pH=6 and 25oC and pH=6.5 and 30oC respectively. Time of fermentation in batch and bioreactor was 54 and 21 hours respectively. High rpm has been caused increasing of microbial growth in bioreactor. The conclusion showed that with optimizing of the growth condition such as some parameters (pH, temperature, substrates and so on) produced SCP with high efficiency. However, produced SCP should be exanimated with other specific tests such as amino acid and fatty acid profiles, minerals, nucleic acids and so on. After full examination, this SCP as probiotic could be used in fish and poultry feed.

Description: Iranian Fisheries Science Research Institute

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Description: At the present study, the water quality parameters monthly, environmental pollutants (pesticides, heavy metals and surfactants) seasonally, macrobenthos and bacteria (monthly) were done 2009 t0 2010 that located in Mangol Dam with longitude and latitude 52° 22' 49" N and 43° 15' 43" E, respectively. All water samples were collected from under-groundwater, surface water and wastewater in 12 stations and the results are as follow: The mean concentrations of DO, BOD5, COD, HCO3-, CO32-, TA, Ca2+, Mg2+, TH, TSS, TDS, Cl-, PO43-, NH4+, NO2- and NO3- were determined about 11.86±0.49, 5.95±0.11, 4.96±0.59, 28.1±6.1, 14.34±1.64, 36.30±2.33, 64.66±2.34, 28.84±1.52, 271.62±8.41, 0.37±0.03, 0.45±0.02, 28.02±1.96, 0.06±0.01, 0.010±0.001, 0.01±0.001 and 0.96±0.03 mg/l, respectively and also temperature, pH and EC were 12.7±0.61°C, 8.00±0.02 unit, 0.57±0.02 ms/cm in all samples. The surface water quality of Haraz River and its tributaries were suitable for usual applications such as aquatic matters, but based on BOD5 need to more attention for human usages. The water quality index (WQI) of surface water was classified in group II at all stations that shows serious water quality changes due to domestic and agriculture sewage. The groundwater was affected by different matters that caused change of water quality parameters. The wastewater was classified from good to moderate based on BOD5. The quality of wastewater was declined at down-stream with decreasing DO and pH and increasing BOD5 pollutants. The mean concentrations of aldrin and endrin were about 0.66 ± 0.59 and 0.71 ± 1.07 µg/l, respectively. The maximum seasonal concentration of organochlorin pesticides (OCPs) were detected in fall, winter and spring for endosulfan sulfate, γ-BHC, heptachlor, endrin aldehyde compounds about 2.85, 0.34, 0.14 and 0.14µg/l, respectively. The maximum seasonal percentage range of OCPs in fall, winter and spring for endosulfan sulfate, DDD and β-BHC were 42, 25 and 25 %, respectively. The maximum seasonal concentrations during fall, winter and spring were detected in Sorkhroud and Polechelave stations for only Fe about 1.48, 3.3 and 8.22 µg/l, respectively. Also for Hg in spring was determined about 17.2 mg/l. The mean concentration of Zn, Fe and Hg in water sampled were 0.23 ± 1.01 and 1.21 ± 2.00 µg/l, respectively and 4.65± 6.38 mg/l. The maximum concentration of linear alkyl benzene sulfonate (LAS) in summer was 971µg/l. The mean concentration of surfactant during fall, winter, spring and summer was 418.62 ± 52.16 µg/l. The maximum seasonal percentage ranges of surfactant during fall, winter, spring and summer in all stations of sampling were 76, 76, 100 and 100 %, respectively. Tottaly 15 families of macrobenthos were identified in Haraz River. The maximum mean of abundance and biomass in Sorkhroud and Nour-roud stations were 1177±256 ind/m2 and 3609 ± 935mg/m2, respectively. During Seasons, the maximum mean abundance and biomass were detected in fall and winter with 1185±444 ind/m2 and 3891±849 mg/m2, respectively. Water quality were classified by Hilsenhoff Biotic Index such as Sorkhrood station as "Very Poor", Isar town station as "Fairly Poor" and Karesang and Nor-roud stations as "good" qualification. The maximum of total coli forms and fecal coli forms in surface water were observed in Sorkhrood about 4.9 and 2.3CFU/100ml, respectively. The maximum of total coli forms and fecal coli forms in groundwater were observed in Halomsar and Absak stations about 4 and 1.7CFU/100ml, respectively. Maximum of total coli forms and fecal coli forms in wastewater were observed in Nor-roud station about 3.1 and 1.6CFU/100ml, respectively. The Ovary of nematode in wastewater were observed in Nor-roud and Isar Town stations about 30 through 124, respectively.

Description: Iranian Fisheries Science Research Institute

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Description: The culture of Iranian Shrimps began in Bushehr in 1372. Early the green or the pink tiger shrimp (Penaeus semisulcatus) which were found in most habitats of the Persian Gulf and Oman Sea were considered in breeding and reproduction, but due to reproduction difficulties, it was rather replaced by the Monodun imported species, then the production of the white shrimp Metapenaeus affinis and Then P.merguensis in some southern areas of the country such as Hormozgan has began in small scale,but none of these species couldn't meet the economical needs of the consumer society and they were not indelible and dominant enough in the shrimp aquaculture industry of the country until breeding of Indian White Shrimp (Fenneropenaeus indicus) has began in large scale in the provinces of Khuzestan and Bushehr, which are seen as the heart of shrimps reproduction and breeding, and in Hormozgan and Sistan. the incidence of white spot viral syndrome (White Spot Syndrom Virus) led to the import of the western white leg shrimp from the USA (P.vannameii) by the Iranian Fisheries Research Organization (IFRO) in 1383, at the present all southern and northern breeding farms of the country (fundamental measures has been carried out in line of shrimp reproduction in Gorgan province in 1386) has put the breeding of this shrimp species as the single breeding species at top of their agenda. The subject of feeding the breeding shrimps is widespread and regarding to the non-proprietary species there are still some species which contain high protein than the other species in studying the different shrimp species requirements. In Iran due to the scarce factories producing the shrimp's food, the alimentary compound of the breeding shrimps during industrializing years of this type of breeding even after the non-aboriginal western white leg shrimp species being inclusive was stable and through different biological processes including: Naplies which feeds from its yalk and by entry into zoa stage start eating only small-sized phytoplankton. And by entry into the stage between zoa and mysis it feeds from phyto and zooplankton simultaneously and entering the post-larva stage it stars sarcophagi. and after 15 post-larva stage entering the growth and transition stage to earthen ponds feeding by concentrated industrial foods in large and small packages depending on young and adult mouth and due to feeding requirements of every stage the alimentary compound is nearly as follows: Digestible protein, energy, fat, carbohydrates, vitamins and minerals will start and the final product will be released in market Or they will be used in the later years of laying eggs and feeding for brood stock. In feeding section the details of every stage and their food's nutritional needs at each stage and will be fully described.

Description: Iranian Fisheries Science Research Institute

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Description: This study was conducted to determine growth parameters, catch and fishing effort trends and stock assessment of mullets in the Iranian coastal waters of Caspian Sea in the years 2015-2016 and 2016-2017. According to the result, the numbers of beach seines were 123 and 120 and their fishing efforts were observed 43588 and 42230 beach seining, respectively. The total catches (including illegal fishing) were also obtained 1542 mt and 2505 mt during 2015-2016 and 2016-2017, respectively. The mean (± SD) of fork length were observed 33.4±5.24 and 33.3±5.72 cm and for total weight were 395.8±142.8 and 395.5±264.52 g in 2015-2016 and 2016-2017, respectively. The frequency of immature individuals were observed 14.2 and 15.7 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 4 to 6 years comprised up to 75.4 and 70 percent, respectively. In fork length – weight relationship a and b were calculated 0.029 and 2.690 for 2015- 2016 and 0.0207 and 2.7914 for 2016-2017, respectively. The Growth parameters of golden gray mullet were K=0.16/yr, L∞ = 64.3 cm, t0 = -0.26/yr. The total and naturaly mortality, Z and M, were calculated 0.81 and 0.35, respectively. Based on catch-at-age data, in the years 2015-2016 and 2016-2017, the total biomass, from the biomass-based cohort analysis were estimated 8170 mt and 7960 mt for golden gray mullet, respectively. In the years 2015-2016 and 2016-2017, the instantanuse fishing mortality F, were 0.25 and 0.46 year-1 and explotation ratio were 0.46 and 0.57, respectively.

Description: Iranian Fisheries Science Research Institute

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Description: The survey sampled during the fourth stage of the season was in 1387. Sampling in eight directions perpendicular (transect) to the beach and 480 samples was performed. In each transect from Astara to the Turkmen 5 stations at depths of 5, 10, 20, 50 and 100 m were selected for sampling. The total number of 191 species was identified; Bacillariophyta category species number was 97, equivalent to %50.8, category of Chlorophyta 28 species, equivalent to %14.7, category of Pyrrophyta 26 species, equivalent to 13.6 %, category of Cyanophyta 25 species, equivalent to 13.1% and category of Euglenaphyta 15 species, equivalent to 7.9% of all species formed. Average abundance of phytoplankton was 27947500(SD=2465184) n/m3 . The average biomass was 125.51(SD=8.84) mg/m3 . Abundance and biomass in spring and summer, autumn and winter have been significant differences (p 〈0.05). The highest frequency was in winter, autumn, summer respectively and spring was (p 〈0.05) and The highest biomass in winter, fall, spring and summer was respectively (p 〈0.05). Bacillariophyta category has the highest abundance equal to 14390833 ± 16262.35 n/m3 (mean ± standard error) were equivalent to %51.49 of the total abundance, Euglenophyta category has the least density equal to 109791 ± 16262.14 n/m3 (mean ± standard error), which is equivalent to % 0.39 of total abundance were included. Also Pyrrophyta category has the highest biomass equal to 69.66 ± 5.53 mg/m3 (standard error ± mean) were equivalent to %53.14 of the total biomass and Chlorophyta category with an average of 0.68 ± 0.11 mg/m3 (mean ± standard error) have the lowest biomass, were equivalent to %0.54 of the total. Phytoplankton Categories in every season, with biomass and abundance have been different (p 〈0.05). Abundance and phytoplankton biomass in the upper layer and lower layer varies with depth of 50 meters (p 〈0.05). With distance from shore and depth increases, reducing the mean abundance and biomass were observed (p 〈0.05). The highest and lowest abundance of phytoplankton was observed at depths of 10 and 100 meters respectively. The maximum amount of phytoplankton biomass in surface areas of deep stations 20 m and the lowest biomass sampled at the deepest point of the station was 100 meters. Abundance and biomass of phytoplankton in the deep layers of the sample with significant difference (p〈0.05) . So that the highest abundance layers of 10 m, the surface layer of 5 m, 20 m, 50 m and 100 m, respectively(p 〈0.05), and the most biomass in the surface layers of 5 m, 20 m, 10 m, 50 and 100 meters, respectively (p 〈0.05). Abundance and biomass of phytoplankton in transects was significant difference (p 〈0.05). Most phytoplankton respectively transect Astara, Babolsar, Anzali Amirabad, Turkmen, Sefidrud, Noshahr, Branch was observed (p 〈0.05) and in terms of biomass, respectively transects Astara, Anzali, Sefidrud, Babolsar, Noushahr, Branch, Amirabad and Turkmen values were higher (p 〈0.05). Species diversity indexe (Shannon – Wiener) phytoplankton was equivalent to 2.92. Environmental conditions and nutrients in different seasons on these parameters influenced the way that species diversity was lowest in summer and in autumn, winter, and spring, respectively, species diversity increased.

Description: Iranian Fisheries Science Research Institute

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Description: In this investigation, were examined the effect of partial harvesting on optimal management of shrimp culture. In order to achieve to the purpose 6Pool0.4/hectare was selected. Three pool with density Twenty-five per sq. m as a witness and another three pond by density fifty per sq. m as the test sample were storage. Based on the results of biometry and biomass estimates of pool was calculated and provided amounts daily meals for shrimps. The first harvest took place after a period of120 days from the test pools .Average of harvest from pools B4, B6andB7 ,was determined respectively, 1373,1365 and1105kg.Second harvest from treatment poolsB4, B6andB7were determined, respectively, 1663,1748 and1783kg. Final harvests from the pools were after 150 day. Harvest average from control pools B1, B2 and B3 was calculated and estimated respectively, 1824, 2000 and 1685 kg. The Average of FCR was calculated 1.51 in control samples. In general, the average of feed conversion rate of the treatment samples were calculated 1.51.We did not see the difference between FCR of control and test samples. According to the project's achievements, we can say, partial harvesting has an important role to increased productivity of shrimp farms in Hellh site from BushehrProvince.

Description: Iranian Fisheries Science Research Institute

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Description: The abundance and biomass of benthic macroinvertebrates were studied in the place of fish cage culture in southern coasts of Caspian sea (Mazandaran waters- kelarabad). The goal of this study was to consider of fish cage culture effects on the abundance and biomass of benthic macroinvertebrates. The sampling was carried out in 3 stations in depth of 20 meter of Kelarabad waters monthly. In this study 7 species were identified belonged to 5 genus of 4 family. Totally 23442 sample of benthic invertebrates were counted that the lowest and highest abundance were in station 1(23.4%) and station 2(46.8%) respectively. The results of stations study showed that the highest abundance and biomass were in stations 2 and 3 with the average of 646 ± 1230.4 n/m2 and 0.526 ± 1.001 gr/m2 respectively. This coulld be respectively dependant to not settling of cage (witness station) and appearance of Cerastoderma glaucum because of its large body in station 1. The difference of abundance and biomass between different stations was not significant (p ›0.05). The study on abundance and biomass in different seasons showed that the highest abundance in autumn with the avarage of 888.13 ± 1371.58 n/m2 belonged to Strblospio gynobranchiata and the highest biomass belonged to C. glaucum which was because of appearance of not native species of polychaeta and also the species with shell covering from bivalvia. The results showed that the specie of S. gynobranchiata from polychaeta including 93.3% of abundance was the dominant specie that could be related to appropriate ecological conditions for living and high adaptability.It was concluded that the abundance and biomass of benthic macroinvertebrates in station 1 was lower than other stations which was related to fish cage culture activity and its effects on benthic macroinvertebrates. So it is suggested that each mariculture activity in southern coasts of Caspian sea should be carried out with regarding to environmental considerations and performance of comparative evaluation project of environmental effects.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was conducted to determine catch and fishing effort trends, length and age composition, growth and mortality parameters and estimate biomass and acceptable biological catch of Kutum in the Iranian coastal waters of Caspian Sea from 2013 to 2015. The catch of Kutum was 6112.8 and 5599.2 tons and CPUE were 181.1 and 183.5 kg/haul in 2013-2014 and 2014-2015, respectively. The mean (± SD) of fork length were observed 39.4±6.1 and 40.7±5.6 cm and for total weight were 805.1±378.0 and 891.5±384.6 gram in 2013-2014 and 2014-2015, respectively. The most predominated of length class was obtained 40-42 cm and frequency of immature individuals were observed 37.8 and 44.4 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 4 to 6 years comprised up to 84 percent. In length – weight relationship a, b and r2 were calculated 0.011, 3.02 and 0.96 respectively. K value, L∞ and t0 were calculated 0.19 (/year), 61.3 cm and -0.99 respectively. Mortality parameters such as Z, M and F were calculated 0.82, 0.36 and 0.46 respectively and Exploitation rate were calculated 0.56. The biomass of kutum estimated 41000 tons and the acceptable biological catch calculated 8250 to 9750 tons. The biomass of Kutum decreased in recently years in spite of produce and release of huge fingerlings. This recruitment (produce and release fingerlings) must be continued for stability of stocks and fishing stress must be decrease by anyway.

Description: Iranian Fisheries Science Research Institute

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Description: In this study ichthyoplankton, phytoplankton, zooplankton, benthics and hydrochemistry parameters were studied. 9 out of 11 sampling stations were in the Gorgan Bay area and 2 of them were in the mouth of the Bay. Ichthyoplankton survey were carried out in 6 stations and the other surveys such as phytoplankton, etc were done in 11 stations in 2009. Gorgan Bay map and position of sampling sites are given at the end of material and methods section. Biomass and frequency of phytoplankton at different stations, months and seasons were calculated that are presented in Tables 1 to 3. Hydro-chemical parameters such as water temperature, air temperature, visibility, DO, BOD5, pH, Alkalinity (bicarbonate, carbonate and total) , Hardness (calcium, magnesium), CL,EC, Salinity, N (nitrate, nitrite, NH3), Phosphate were measured and results are shown Table 11 . Biomass (mgr/m3) and numbers (ind./m3) of 47 genus of different phylum of phytoplanktons such as Cyanophyta, Chlorophyta, Pyrophyta, Chrysophyta and Euglenaphyta as well as different phylum of zooplanktons consist of Protozoa, Arthropoda, Rotifera and Cyliophora were estimated. Frequency of phytoplanktons (ind/m3) was 131.2, 1.6, 65.3, 18.9 and 23.8 millions respectively. Furthermore, their biomass was 308.4, 1.9, 1358.9, 295.1 and 124.7 mg/m3, respectively. The maximum and minimum numbers were observed in Leptolingbaya belonged to Cyanophyta and Diatoms of Chrysophyta 84.3 and 0.025 million ( ind/ m3) respectively. The maximum and minimum biomass was observed in Gyrosigma (Chrysophyta) and Tetradron (Chloropyta), 12317.3 and 0.014 mg/m3 respectively. The average biomass of zooplankton was measured 531.74, 30.77, 225.07, and 96.26 mg/m3 respectively and the total was attained 883.83 mg/m3 Table 5 . The maximum and minimum biomass of all zooplanktons was estimated in November and July, 3446.23 and 6 mg/m3 respectively. Furthermore, the maximum and minimum numbers of zooplanktons were found in September and July which were 48.4 and 0.002 millions respectively and the average number was 8.4 ind/m3 Table 4 . Also numbers and biomass (gr/m2) of 11 families of benthos which inhabit Gorgan Bay such as Annelida, Mollusca and Arthropoda were investigated in separated stations and distinctive months. The maximum and minimum biomass of benthos was observed in January (42.91 gr/m2) and March (0.6428 gr/m2). The biomass was considerable in April, February, August and December (Tables: 4, 5 and 6).

Description: Iranian Fisheries Science Research Institute

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Description: Sediments samples were collected using Veen Grab Sampler (0.1 square meter) at 8 transects namely Astara, Anzali, Sefidroud, Tonekabon, Noshahr, Babolsar, Amirabad, Torkman in the southern of Caspian Sea. Five stations were selected at 5, 10, 20, 50 and 100 meter depths in each transect. Sediments were sampled triplicate at each station. Samples also were collected during four seasons (spring (May), summer (July), fall (November) and winter (January)) in 2009. Results of this study showed that species composition of Macrobenthos consisted of 32 species which belonged to 7 families of Polychaeta, Crustacea and Bivalvia at studied area. In addition, Oligochaeta identified in “Class”, Chironomidae considered in Insecta categories “Family” and Streblospio spp. (Polychaeta) was recognized in “Genus”. Gammaridae and Pseudocumidae of Crustacea with 12 and 10 species had the highest species diversity compared to other groups, respectively. Polychaeta was consisted 75.5 percent of total abundance of macrobenthos which the major abundance (equal 62.4% of total abundance) were belong to Streblospio spp. from Spionidae family, while its biomass was equals 5.11% of total macrobenthos. In contrast, Cerastoderma lamarcki species from Bivalvia Class with only 1.7% of total abundance of macrobenthos allocated 69 percent of total biomass. In the southern of Caspian Sea, average total abundance was significantly less at 4 western transects (Astara, Anzali, Sefidroud, Tonekabon) compared to 4 eastern transects (Noshahr, Babolsar, Amirabad, Torkman) (p〈0.05). The highest average abundance of macrobenthos (10655±1246SE ind/m2) was observed at transect of Torkman, and lowest value (4032 ± 686SE ind/m2) was recorded at transect of Sefidroud (p〈 0.05). Generally, minimum species diversity were obtained at 20 m depth in all transects and the maximum value was observed at 5 m depth in most of transects (p〈0.05). In contrary, maximum average abundance of Macrobenthoses was at 20 m depth in transects of Anzali, Sefidroud, Tonekabon, Nowshahr and Amirabad compared to other depths. Macrobenthoses abundance average in 5 m depth (except Astara and Torkman) was less than other depths in 6 transect (p 〈 0.05). Total average abundance and biomass of macrobenthos was 5976±583SE ind/m2 and 43.675 ± 11.402SE gr/ m2, respectively. Maximum and minimum of abundance of macrobenthos were observed in summer (7714±778 ind/m2) and winter (4071 ± 340 ind/m2), respectively. Maximum and minimum of biomass of macrobenthos were obtained in fall (50.271±13.258SE gr/ m2) and in summer (35.123 ± 8.903SE gr/ m2), respectively (p〈 0.05). Percent of total organic matter (TOM) were low in 5 and 10 m depths and increased toward offshore depths. TOM percent was 2.06±0.11SE at 10 m depth and increased to 4.62 ±0.17SE in 100 m depth. Percent of silt and clay (grains size less than 63 micron) had positive significantly correlation with percent of TOM (p〈0.01).While they had negative significantly correlation with percent of sand (grains size between 63 and 1000 micron) (p〈0.01). Percent of silt and clay like organic matter, had ascending trend toward to depth increased and varied from 44.4 ± 4.06SE percent in 5 m depth to 96.5 ± 0.59SE percent in 100 m depth. In contrast, percent of sand decreased toward depth and varied from 54.5 ± 4.13SE percent in 5 m depth to 2.8 ± 0.53SE percent in 100 m depth. Result of current study showed that total abundance of macrobenthoses had positive significantly correlation with TOM percent (p〈0.01) and silt/clay percent (p〈0.05). Abundance of Oligochaeta had positive significantly correlation (p〈 0.01) with TOM and silt/clay percent. Two groups of Polychaeta, Gammaridae and Cerastoderma lamarcki had negative significantly correlation with TOM and silt/clay percent (p〈 0.01), and every four aforementioned groups had positive significantly correlation with sand percent (p〈 0.01). Overall, different correlation between abundance of various macrobenthos groups and TOM percent and type of grain size of sediment could be related to fluctuation of abundance of various macrobenthos groups at difference transects and depths. On the other hand, in study area were occurred simultaneously some phenomena such as increased abundance of Oligochaeta and Polychaeta, dominance of Streblospio Genuse (Polychaeta group), and decreases abundance of Bivalvia and appearance of Menemiopsis leidyi which need to study more and monitoring of this area.

Description: Iranian Fisheries Science Research Institute

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Description: Recently, we have been encountered to increasing jellyfish biomass in the world tropical coastal waters and due to their role in ecosystem food web, can be made direct and indirect effects on marine stocks and causing problems for fisherman’s communities. Now, the number of studies on this animal groups and factors which caused to jellyfish bloom has been increased. Present study was carried out for identification and density estimation of jellyfishes in the East and West coasts of Khure-Musa canal in Khuzestan coastal waters in North-West of Persian Gulf. Monthly samples were collected by two sampling methods from randomly sites in studied area in day light during February 2007 to January 2008. Small jellyfishes were collected by using 500 micron mesh net and density was calculated as number per 10 square meters. Large jellies were collected by using shrimp trawl net and quantity measurements were done by swept area methods. Totally, 18 species including 9 hydromedusae, 2 Scyphomedusae, 3 Siphonophorae and two Ctenophores were identified. Generally from 5357 separated small jellyfish, 56.6 % was from East and 43.4 % was from west coasts. Ctenophore, Pleurobranchia (31%) and then the Hydromedusa Eiren hexanemalis (22%) were the most abundant taxa. The maximum number of jellyfish (1080 per 10m2) was observed in western coasts in July and then decrease in summer and autumn. In contrast to Eastern coasts, the highest frequency (655 per 10 m2) was observed in western coasts in September. Two peaks of frequency in May-June and in summer to fall were observed in this area. The highest frequency of macro jellyfishes were in July and mostly in East coasts (2811 per km2). During February 2007 to February 2008 Catostylos tagi and Chrysoara hysocello were dominated. Monthly jellyfish abundance variation showed inverse relation between Eastern and Western coasts. The maximum diversity was in August in Eastern coast and July in Western coasts. The minimum values were calculated in winter months in two areas. Obviously, with increasing jellyfish abundance, in summer months, fish larvae population decreased. Jellyfish explosion can be caused by several factors, fishing pressure and removing top predators from food web, climate change, global warming and eutrophication phenomena are defined as the major factors in jellyfish bloom in worldwide tropical coastal waters. Therefore human activities enhance the occurrence of this phenomenon. Recent drought, decreasing freshwater input, increasing waste discharge and overfishing are probable causes for jelly blooms in Khuzestan coastal waters.

Description: Iranian Fisheries Science Research Institute

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Description: Due to various Physic and chemical factors of rivers leading to the sea, the situation seems different topography and throughput rate initial productions in the different seasons and due to various circumstances physical and chemical rivers leading to the sea, seabed topography in different situation appears to be of primary production in the eastern and western between the Caspian Sea in the season, may be altered.Identifying species and determining the distribution and biomass of the changes and how they are affected by environmental changes and we are environmentally conscious. We also compare the current situation with previous studies, we find that the number and types of plankton biomass have been what it is. During 1392 in spring, summer, autumn and winter, in a study of 8 transects of 40 stations. In each transect from Astara to the Turkmen. 5 stations at depths of 5. 10 and 20 m were selected for sampling. The total number of 182 species from seven branches Bacillariophyta, Pyrrophyta, Cyanophyta, Chlorophyta, Euglenophyta, Xantophyta and Chrysophyta phytoplankton were identified. Including 81 species of Bacillariophyta, 33 Cyanophyta, 25 Pyrrophyta, 31Chlorophyta , 9 Euglenophyta, 1 Xantophyta and Chrysophyta had 1 specie. Most of Bacillariophyta (61 species) was in Autumn and then in winter (48 species). Dominant species of Bacillariophyta were Pseudonitzschia seriata, Rhizosolenia fragilissima, Stephanodiscos sp. , Melosira varians, Nitzschia acicularis and Cyclotella menenghiniana Pyrrophyta was greatest diversity of branches in summer, autumn and winter (19 species), which includes Exuviaella cordata, Exuviaella marina, Prorocentrum praximum and Prorocentrum scutllum. In the autumn density of Cyanophyta was 285/7(± 137/1) cubic meters × 106 and biomass was 95( ± 54) mg per cubic meter) and 18 species were observed. The dominant species in this category were Oscillatoria sp., Nodularia spumigena and Oscillatoria agardhii. Most species of Chlorophyta branche in autumn and winter and summer median region with the highest density at the density of 26/2% and most of it is Binuclearia lauterbornii. Identified as the branches Euglenophyta were Trachelomonas, Euglena and Phacus that were observed in all seasons. In winter, the highest mean biomass was 9( ± 0/818) mg per cubic meter and the highest density of in summer was 0/5 ( ± 0/5) in cubic meters × 106. In winter the depth of 10 meters and surface of Babolsar, Amir Abad and Anzali, a kind of Chrysophyta and in surface of Tonekabon and Anzali a species of Xantophyta were observed that had negligible density and biomass. Studies have shown that density and biomass of Bacillariophyta were 228 (± 471) per cubic meter × 106) and 6157 ± ( 290) mg per cubic meter) respectivity and Pyrrophyta were 28/17( ± 27/14) cubic meter × 106in cubic meters) and 3349 ( ± 336) mg per cubic meter) and Cyanophyta 120/40 (± 123/87) per cubic meter × 106 per cubic meter), biomass (55 ± 57mg per cubic meter) were the branches of the dominant phytoplankton. Abundance and biomass in different seasons have been significant differences (p 〈0.05).

Description: Iranian Fisheries Science Research Institute

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Description: Present study was conducted in shrimp farm located in east of Chabahar in Sistan and Balouchestan province from August 2001 until May 2003. Fourteen stations at three locations (i.e. supply channel, drainage channel and Gwatr Gulf) were selected to determine physical and chemical factors such as; temperature, salinity, dissolved oxygen, pH, nitrate, nitrite, ammonia, phosphate, silicate, total suspended solid and turbidity. Sampling was conducted twice a month during the shrimp culturing period and monthly at other times. Water samples were collected every two weeks to determine Chemical and Physical factors, Chlorophyll a, Phytoplankton and Zooplankton. Sediment samples were collected seasonally to examine Macrobenthos, Grain size and Total Organic Matter. The results revealed different bioenvironmental area in the three locations (i.e. supply channel, drainage channel and Gwatr gulf) over the study period. One-way analyze of variance of chemical and physical factors indicated significant difference between different times as well as different stations (p〈0.05). The negative relationship was observed between the culturing production area and the amount of average dissolved oxygen, pH and total suspend solid. An increase in the culturing production area in 2002 as compared to that of 2001 causes a decrease in the amount of these factors. However, it dose indicates positive relationship with nitrate, nitrite, ammonia, transparency and chlorophyll. Forty nine phytoplankton genus were identified, which mainly belong to diatoma, dinoflagellate and green blue algae. Diatom was dominated among these groups. Diatom and green-blue algae and diatom comprised %79, %69 and %64 of phytoplankton flora respectively in supply channel, Gwater Gulf and drainage channel. Copepod and thintinnida were the major groups of zooplankton. High abundance of bivalve, Polychaetes and amphipoda were found in supply channel, Gwatr Gulf and drainage channel respectively. Analysis of grain size showed the existence of sandy sediment in Gulf of Gwatr and sandy-loom in supply channel. Drainage channel sediment found to be sandy-loom, sandy-silty-loom and sand loom. Among three locations, the highest TOM was found in drainage channel. In last location, production area in 2002 increased as compared to that of 2001, which showed negative relationship with salinity, nitrate, nitrit, ammonia and chlorophyll a. Drainage of the Gwatr s shrimp farm did not cause any thermal contamination in the location. Shrimp aquaculture activities caused an increase in the average of salinity, range of pH in the Gwatr Gulf.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was carried out in Bushehr province waters (49ْ 40E and 30ْ 00N to 52ْ 00E and 27ْ 40N) in July and August 2010-2011. The objectives of this study were to determine the opening and closure periods of shrimp and to estimate of the shrimp biomass in the study area. Based on the total length, the opening season of shrimp fishery in 2010 and 2011 were proposed on 12 and 22rd of July, respectively. The closed season was determined based on the remaining of 20% of shrimp stock and proposed on 12 and 29th of August, respectively. The primary estimation of the biomass in these years was 840 and 455 metric tones, respectively. While the total catch were estimated 847 and 859 tones in these years. During this study 9 species of the penaeid and solenoserid species were identified. The percentage of the green tiger prawn to the other species in the study years were 73% and 92%, respectively.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Regarding to monitor of demersal resources in the Persian Gulf and Oman Sea, and also biomass and CPUA estimation of them, ten research cruises were carried out by using R/V Ferdows-1 equipped with bottom trawl, covering the area from 49º 00´ E in the west (north-west Persian Gulf) to 61º 25´ E in the east (borderline with Pakistan) from 2012 to 2014 The study area was stratified into 17 strata (A to Q) of which 10 strata (A to J) were in the Persian Gulf and 7 strata (K to Q) were in the Oman Sea, covering the depths of 10-50 m in the Persian Gulf and 10-100 m in the Oman Sea. A total of 316 stations were randomly selected and the biomass and CPUA were estimated by swept area method During this three years period, the strat A and B weren’t covered. The comparison between two regions indicated that the percentage of density of demersal fishes in the Persian Gulf during years 2012, 2013 and 2014 were 1.0, 1.4 and 1.6 times more than the Oman Sea and totally 50-60% of total biomass was found for the Persian Gulf. Also a comparison among 17 strata the highest biomass was found for K region (Sirik to Jask) in the Oman Sea in 2012 & 2014; and C region (Genaveh to Bordkhoon) in 2013 in the Persian Gulf. The same comparison was done for CPUA of commercial, non-commercial and total in both water bodies and it was found that in years 2012 to 2014 the region K (Sirik to Jask) in the Oman Sea and Stratum Q (Bersi to Gwatr) had the highest value of CPUA. On the contrary, the startum M (Biahi to Galak estuary) showed the lowest value of biomass for both commercial and non-commercial fishes. With review the mean CPUA in defferent depth layers for years 2012, 2013 and 2014, it was concluded that in the Oman Sea with increasing the depth, the mean CPUA is decreased and the lowest CPUA belongs to depths of 30-50 m The comparison between commercial and non-commercial groups in both ecosystems, it concluded that the density of commercial species were higher than non-commercial ones; and for years 2009, 2010 and 2011 the commercial species consist of 63.4, 65.0 and 59.7 % of total biomass. In all years the Persian Gulf indicated higher values than the Oman Sea. The most abundant fishes were Rays, Ribbon fishes, Carangids, Grunts, Japanese threadfin bream, Lizardfish and Barracuda for both Persian Gulf and Oman Sea.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Regarding to monitor of demersal resources in the Persian Gulf and Oman Sea, and also biomass and CPUA estimation of them, ten research cruises were carried out by using R/V Ferdows-1 equipped with bottom trawl, covering the area from 49º 00´ E in the west (north-west Persian Gulf) to 61º 25´ E in the east (borderline with Pakistan) from 2012 to 2014 The study area was stratified into 17 strata (A to Q) of which 10 strata (A to J) were in the Persian Gulf and 7 strata (K to Q) were in the Oman Sea, covering the depths of 10-50 m in the Persian Gulf and 10-100 m in the Oman Sea. A total of 316 stations were randomly selected and the biomass and CPUA were estimated by swept area method During this three years period, the strat A and B weren’t covered. The comparison between two regions indicated that the percentage of density of demersal fishes in the Persian Gulf during years 2012, 2013 and 2014 were 1.0, 1.4 and 1.6 times more than the Oman Sea and totally 50-60% of total biomass was found for the Persian Gulf. Also a comparison among 17 strata the highest biomass was found for K region (Sirik to Jask) in the Oman Sea in 2012 & 2014; and C region (Genaveh to Bordkhoon) in 2013 in the Persian Gulf. The same comparison was done for CPUA of commercial, non-commercial and total in both water bodies and it was found that in years 2012 to 2014 the region K (Sirik to Jask) in the Oman Sea and Stratum Q (Bersi to Gwatr) had the highest value of CPUA. On the contrary, the startum M (Biahi to Galak estuary) showed the lowest value of biomass for both commercial and non-commercial fishes. With review the mean CPUA in defferent depth layers for years 2012, 2013 and 2014, it was concluded that in the Oman Sea with increasing the depth, the mean CPUA is decreased and the lowest CPUA belongs to depths of 30-50 m The comparison between commercial and non-commercial groups in both ecosystems, it concluded that the density of commercial species were higher than non-commercial ones; and for years 2009, 2010 and 2011 the commercial species consist of 63.4, 65.0 and 59.7 % of total biomass. In all years the Persian Gulf indicated higher values than the Oman Sea. The most abundant fishes were Rays, Ribbon fishes, Carangids, Grunts, Japanese threadfin bream, Lizardfish and Barracuda for both Persian Gulf and Oman Sea.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Mnemiopsis leidyi is one the species of comb-jelly. It belongs to the Ctenophore phylum and Lobate order. It is a purely marine, free-swimming animal with a transparent jelly-like walnut-shaped body, which was transported from the Black Sea into Caspian possibly at the end of 1990s. This species is food rival of pelagic fish. It has been reported that the ctenophore caused the dramatic decrease of zooplankton and pelagic fish stock in the Black Sea. In this study, sampling on Mnemiopsis leidyi, zooplankton, phytoplankton was conducted from December 2003 to March 2005, from a total of 11 stations located along four transects (Anzali , Khazarabad, Tourkman and Gorgan Bay) by METU net in the Iranian coasts of the Caspian Sea. Clupeonella catch was done by light fishing with fishing vessel in Anzali region. The results showed that the biomass of M.leidyi had some fluctuation in different seasons and its maximum biomass was recorded in summer with a figure of 524.4±156.2 g.m2 Tourkman region and the minimum biomass was observed in winter with a figure of 5.15±1.81 g.m2 in Anzali region. Study of stomach of Mnemiopsis showed, that Acartia (belonged of Copepoda with 66 %), lamlibranchia (13 %) has the highest frequency and the lowest were Balanus nauplii, Rotatoria, Tintinnopsis and Podon polyphemoides. The maximum mean abundance of zooplankton was 29368±24318 n.m3 in winter (Anzali region) and the minimum was recorded 4170±5014 n.m3 in summer (Tourkman region). Copepoda was dominant zooplankton in the Iranian coasts of the Caspian Sea. Chrysophyta with 150000000±440000000 n.m3 and Euglenophyta with 260000±521000 n.m3 had the highest and the lowest frequency respectively in the Caspian Sea. The main foods of Clupeonella were Acartia with 80 %. The survey of stomach of Clupeonella showed that the feeding of these species was not good and the highest fullness index was recorded 220.95±314.67. These results showed, the main food item of Ctenophora and Clupeonella were Copepoda (Acartia). It seems, the impact of Mnemiopsis leidyi feeding has been the important factor in declining zooplankton populations, Clupeonella stocks, and also increasing of phytoplankton abundance.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This survey was carried out by R/V Gilan with a conical plankton net of 100 micron mesh by vertical hauls at 8 transect in the southern Caspian sea. Transects were located at Astara, Anzali, Sefid roud, Tonekabon, Noshahr, Babolsar, Amirabad and Torkman in depths of 5, 10,20,50and 100m. Samples were taken in 4 seasons ( in each season 64 samples) in 2009. In this study 23 species formed the zooplankton community including 4 species of Copepoda, 8 species of Rotatoria, 2 species of Protozoa and 8 species of Cladocera. The meroplankton blonged to 2 species of Balanus sp and Lamellibranchiata larvae. The annual results revealed that the maximum abundance of Copepoda were 3612±4839 ind/m3 and 35/75 ±42/81 mg/ m3 in summer and decreased gradually since autumn and reached to minimum value in winter. The maximum abundance of Cladocera was 300± 383 ind/m3 in spring and reached to less than 4 ind/m3 in summer and autumn. The Rotatoria had high population (3775± 8632 ind/m3) in winter which consisted the zooplankton population with Copepoda. The Protozoa had no efficient role in zooplankton population of Caspian sea during the year. The zooplankton population was affected by Meroplankton and Lamellibranchiata larvae in spring and winter. The Copepoda contributed in zooplankton population only in summer and autumn. The maximum zooplankton abundance and biomass were in 5m depth which included 10209±8352 ind/m3 and 43/56±26/08mg/ m3 in spring, 8545±7127 ind/m3 and 73/59±56/65mg/ m3 in summer(10 m depth), 8427±6711 ind/m3 and 43/15± 29/59 mg/ m3 in autumn and 24426 ±26975 ind/m3 and 334/25±392/21 mg/ m3 in winter which decresed from surface to depth. The maximum abundance and biomass of zooplankton were 5119±6018 ind/m3 in east and 28/59±24/79 mg/ m3 in central area in spring, 6628±7117 ind/m3 in west area and 50/73±59/52 mg/ m3 in central area in summer, 5248 ±5489 ind/m3 and 31/16 ±31/22 mg/ m3 in west area in autumn and 11588±16191 ind/m3 and 131/02±193/61 mg/ m3 in west area in winter. The annual statistical analysis reveals that there is significant difference between Copepoda and Cirripedia population among seasons, sampling stations, depth and sampling layer (Kruskalwallis test, p〈0.05) and the total zooplankton populatin had no significant difference only between seasons (Kruskal-wallis test, p〉0.05). The Cladocera, Lamellibranchiata larvae and the Rotatoria had significant difference between seasons only (Kruskal-wallis test, p〈0.01).

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Exploitation of bony fishes resources started on 12 October 2005 and finished on 9 April 2006 in 2005-2006. 142 beach seines caught about 14333.4 tons of bony fishes by 47101 hauling. The total catch was estimated 21844.7 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 97 percent of total catch. Length classes 39-40, 31-32 and 40-41 cm predominated for kuttum, golden grey mullet and common carp, respectively. Age groups 3 to 5 year comprised 84.2, 74.8 and 83.7 percent for Kuttum, golden grey mullet and common carp, respectively and age group 4 year was dominant with 42.0, 35.9 and 43.0 percent, respectively. K value and L∞ calculated 0.26 (/year) and 58.3 cm for Kuttum and 0.15 (/year) and 61.5 cm for golden grey mullet, respectively. The total biomass and MSY estimated about 24733.7 and 8550.4 tones for kuttum and about 16948.0 and 4999.0 tones for golden grey mullet, respectively. Exploitation rate (E) calculated 0.71 and 0.70 for Kuttum and golden grey mullet, respectively. In 2006-2007, the exploitation of bony fishes resources started on 12 October 2006 and finished on 7 April 2007 in 2006-2007. 134 beach seines caught about 14120.0 tones of bony fishes by 48470 hauling. The total catch was estimated 23801.8 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 98.5 percent of total catch. Length classes 39-40 and 38-39 cm predominated for kutum and common carp, respectively and length classes 27-28 and 29-30 cm predominated for golden grey mullet. Age groups 3 to 5 year comprised 80.2 and 71.8 percent for kutum and golden grey mullet, respectively and age groups 4 to 6 year comprised 71.8 percent for common carp. Age group 3, 4 and 5 year was dominant with 35.5, 32.1 and 27.1 percent for kutum, golden grey mullet and common carp respectively. K value and L∞ calculated 0.27 (/year) and 60.7 cm for Kutum, 0.2 (/year) and 58.4 cm for golden grey mullet and 0.19 (/year) and 66.7 cm for common carp, respectively. The total biomass and MSY estimated about 46654.9 and 14801.4 tones for Kutum, about 19549.0 and 5748.4 tones for golden grey mullet and about 10584.3 and 2186.0 tones for common carp, respectively. Exploitation rate (E) calculated 0.69, 0.53 and 0.52 for kuttum, golden grey mullet and common carp, respectively.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Mnemiosis leidyi is one the species of comb-jelly. It belongs to the Ctenophora phylum and Lobata order. Mnemiopsis leidyi first appear in the Black Sea in 1980s and reached to the biomass levels up to 1.5-2 kg m2 in the Summer of 1989. This species is food rival of pelagic fish. It has been reported that the ctenophora caused the dramatic decrease of zooplonkton and pelagic fish stock in the Black Sea. In this study, sampling on Mnmiopsis leidyi, zooplankton and phytoplankton started from July to December 2002 from a total of 2 stations located Anzali and Khazarabad by METU net in the Iranian Coasts of the Caspian Sea. Experimental studies on Mnemiopsis have indicated that Mnemiopsis begins to produce eggs in the Caspian Sea, when it reaches length about 15 mm. Although eggs were obtained even from specimen with 12 mm length and weight of 0.5 g. The most abundant size of reproducing Mnemiopsis was 20-30 mm in the Caspian Sea. Average fecundity of M.leidyi in the Caspian Sea was 1174±741 eggs/day with maximum 2824 eggs/day for specimens with length group of 30-39 mm and the weight about 2.0-2.7 g. Percentage of hatched eggs was not high in experiments with M.leidyi the range from 9 to 92 % after 24 hours. The maximum produce egg of M.leidyi measured with mean 845±733 eggs/day in Salinity of 11 ppt and the minimum egg recorded with mean 2 eggs/day in salinity of 4 ppt. The results showed that the biomass of M.leidyi had some fluctuation in different months and its maximum biomass was recorded in August with a figure of 384±156 g.m2 and the minimum biomass was observed in December with a figure of 87±46 g.m2 . The gut contents of Mnemiopsis leidyi showed a wide variety of prey including 84 % of zooplanktons and 16% of Phytoplanktons.The most abundance of intaked foods was Acartia (belong to Copepoda ) with 34 % and the least was podon polyphemoides (belongs to Cladocera) with 0.74 %. Also 3.0 % of fish eggs and 4.2 % of Lamllibrachia were found among stomach contents.The young specimen (5〈 mm) consumed more zooplanktons and phytoplanktons comparing to adult ones. Copepoda was dominant zooplankton in the Iranian coasts of the Caspian sea. Fecundity of Mnemiopsis showed correlation to the length and wet weight in the Caspian Sea and reprodaction of M.leidyi was done small size in comparing with other area in the Caspian Sea. Salinity, water temperature and food availability is the most important factor in producing eggs in M.leidyi. It seems, that Mnemiopsis leidyi feeding has been one of the most important factor in declining zoolankton populations and Clupeonella stocks.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In order to determine the impact of the new invasive ctenophore (Mnemiopsis leidyi) of the Caspian Sea, it is needed to monitor the temporal and spatial distribution as well as seasonal biomass fluctuation of this animal. At the present study, sampling was conducted in 8 transects such as Astara, Anzali, sephidroud, Tonekabon Nowshar, Babulsar, Amirabad and Bandar Torkaman. Each transect had four stations located at the points off the shore where the bottom depth was 5, 10, 20 , 50 and 100m, respectively. Ctenophore samples were collected with planktonic net and simultaneously some morphometric characteristics such as weight, length, abundance and biomass were measured. Statistical analysis was done based on the averages of year, season, location, depth and size of the M. leidyi. In 2008, mean abundance and biomass of M. leidyi were recorded 63±7 ind.m3 and 7.70±2.34 g.m3, respectively. M. leidyi abundance and biomass were ranged of 0-639 ind.m3 and 0-158 g.m3, respectively. The maximum seasonal average of abundance was 150 ± 17 ind.m3 while the maximum biomass was 26.59± 4.61.m3 in summer. There is a significant different between abundance and biomass in summer and autumn, respectively (p〈0.05). Comb jelly length in autumn was smaller than in summer. Minimum M. leidyi abundance was observed in spring (4.0±0.7ind.m3) and winter (6±2ind.m3). The lowest average of seasonal biomass was observed in winter (0.50±0.07 g.m3). The maximum of M. leidyi biomass was recorded at the depth 5m of Anzali in summer 2008 with 639 ind.m3 and 158 g.m3, respectively. There was not significant different between abundance and biomass in various transects (p〉0.05). The results showed that the highest abundance and biomass coincide to photic zone (≤ 20 m in depth) in which there is a significant different between photic zone and various layer (p〈0.05). The maximum ctenophore size was recorded 55 mm in 2006 and 60 mm in 2007, in which it was 50 mm in 2008. The data of M. leidyi from 2001 to 2008 indicated that abundance and biomass of comb jelly decrease in trend. Therefore, the results showed that the M. leidyi is a superficial and littoral species in the southern Caspian Sea.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The present survey was conducted for evaluation of environmental impacts of shrimp farm effluents in Tiab district of Hormozgan province. During the growing season of 2003(Jul-Dec) water and sediment samples have taken with monthly intervals from inflow and outflow of the farms and related coastal waters adjacent to Tiab estuary. The samples were carried to the laboratory for physical, chemical and biological analyses. The results showed that the farms exert significant influence on humidity of surrounding air. Furthermore most of the measured parameters such as pH, salinity, BOD5, COD, ammonia, nitrite, nitrate, phosphate, TP, total phytoplankton and zooplankton numbers in water column and the percentages of the TN of sediments of the outflow waters were adequately higher than inflow water, but reverse results were measured for oxygen content of the water and total macrofauna numbers. There were no any significant differences between inflow and outflow channels in the case of temperature and TN of the water. In the statistical analyses, station effect only showed significant influences on variation of zooplankton numbers, TN, COD and salinity of the water and the percentage of sediment total organic compounds. The results also showed that during the growing season in the surveyed channels the most values of water and air temperature, air moisture, salinity and COD decreased, but in contrast the magnitude values of pH, BOD5, nitrite, nitrate, phosphate, TP and total phytoplankton and zooplankton numbers increased during the same time. The month effect significantly influenced the preceded noticed parameters, but had no significant effect on variation of other parameters such as: TN and total macrofauna of the water column and percentages of total organic compounds and nitrogen of the sediment. The results showed that there were no significant differences between the surveyed channels and coastal waters in the case of measured values of water and air temperature, pH and oxygen content. Higher total phytoplankton numbers were measured in the coastal waters, but most of other surveyed parameters were high in the channels. In the coastal waters the variations of most measured parameters were managed by winds and the related waves and turbulences, so water exchange with Tiab estuary had no significant effect in this respect.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In the years 2007-2007, 2008-2009 and 2009-2010 the exploitation of bony fishes resources (by 131 beach seines) started on 12 October but finished on 9 April, 9 April and 13 April, respectively. During these periods the total catch of bony fishes were 23537.8, 20045.5 and 18664.8 tonnes, respevtively. During these periods, kutum predominated and represented the highest proportion of total catch at 73.1, 74.0 and 66.9% , followed by golden grey mullet at 18.3, 13.9 and 18.7%, respectively. K values calculated 0.22, 0.15 and 0.14 year-1 and L∞ were 66.0, 62.7 and 70.0 cm for kuttum, golden grey mullet and common carp, respectively. The instantaneous coefficient natural mortality were estimated as 0.386 and 0.35 year-1 for kutum and golden grey mullet, respectively. During three periods, the exploitation rates were 0.789, 0.584 and 0.614 for kutum and 0.71, 0.75 and 0.61 for golden grey mullet, respectively. In the years 2007-2007, 2008-2009 and 2009-2010, the total biomass, from the biomass-based cohort analysis were 56600, 62090 and 61590 tonnes for kutum and and MSY estimated about 24733.7 and 8550.4 tones for kuttum and 11040, 11900 and 14460 tonnes for golden grey mullet, respectively. The ABC (acceptable biological catch) were estimated as 8000 and 2200 tonnes.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: One of the effective factors in cyst production on Artemia culture ponds is the number of oviparous females and density of biomass in view of adult's weight per liter of ponds water. In this study, the effect of oviparous female's abundance (Reproductive Females lit-1) on daily cyst yields with using the ANOVA and correlation Analytical method were assayed. The result indicated that, with presence the small number of oviparous females (less than five Ind lit-1) and Artemia density (between 0/1to0/2g/ lit) on culture ponds, the cyst yields at first sixty days culture period (160 Kg.dw/ha) were more than yields that harvested at three months later (47Kg.dw/ha) and on the second three months of cultural period despite of presence the larger number of oviparous females (more than twenty Ind/lit) and presence the same Artemia population density, the daily cyst yields was declined.(Sig=0.000).

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Present project was conducted in shrimp farm located in east of Chabahar in Sistan and Balouchestan province.Twentieth sampling stations at three locations (i.e. 2 stations in supply channel,13 stations in drainage channel and 5 stations in Gwatar Gulf) were selected to determine physical and chemical factors such as; temperature, salinity, dissolved oxygen, pH, nitrate, nitrite, ammonia, phosphate and biological parameters for example Chlorophyll a, phytoplankton and zooplankton. Sampling was conducted once a month from March 2003 until January 2004. The results revealed different bioenvironmental area in the three locations (i.e. supply channel, drainage channel and Gwatar Gulf) over the study period. Concentration of salinity ,pH , nitatr ,nitrite ,ammonia and chlorophyll a in drainage channel were more than supply channel and Gawtar Gulf. While concentation dissolved oxygen and phosphate were in drainage channel less than Gawtar Gulf.Also, sediment with small grain size (clay and silt) caused uptake phosphate and amount phosphate decreased in drainage channel. Considering with lack of environment standards in Iran shrimp effluent, data compared with others countries standard. Results showed that with considerable farm area , value of temperature , salinity , dissolved oxygen and pH were in permit range in Gwatar Gulf while concentation nitrate, phosphate and chlorophyll a were sometimes more than permit range that could cause plankton bloom.Also, Gwatar Gulf were influence monsoon. Nitate , phosphate , chlorophyll a and phytoplankton increased in gwatar Gulf.Regards with that postmonsoon was simultaneus with shrimp harvest.Therefore, increase some parameters could be caused from shrimp effluent or postmonsoon. Thirty four phytoplankton genus were identified including diatoma, dinoflagellate , cyanophyta and chlorophyta. In each area maxiumum percentage of phytoplankton were belonged to diatoma( 63%) in supply channel , cyanophyta(51.7%) in drainage channel and dinoflagellate (94.5% ) in Gwatar Gulf.Amount and range chemical and physical factors and plankton composition were different in drainage channel , supply channel and Gwatar Gulf. Cyanophyta could grow more in drainage channel.Percentage of aboundance and diversity of phytoplankton changed in 2002 inrelation to years ago( before shrimp culture , 2000 year and 2001 year) specially in Gwatar Gulf.Mainly percentage of zooplankton were copepoda and thintinida respectively.Diversity zooplankton decreased ratio to years ago. In drainage channel , abundance total of phytoplankton and zooplankton were more than Gwatar Gulf and supply channel.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The marine survey for sturgeon stock assessment was conducted in summer, winter and spring in the years 2006 and 2009 to estimate the relative and absolute abundance and percentage composition of each species in the Guilan, Mazandaran and Golestan Provinces. This survey was carried out in the Iranian waters of the Caspian Sea on board the Sisara2 and Guilan vessels using trawl nets at 2-100 m depths. Trawling was carried out in 85 stations that were selected using a stratified random design. The number of stations in each scope was based on the area of the scope in terms of the total area. Trawling and sampling in shallow water up to 10 m were carried out using 9 m trawl nets whereas 24.7 m trawl nets were used for depths more than 10 m. Trawl surveys were carried out in the daytime. Trawling velocity was kept at 2.5-3 kts and trawls lasted half an hour in order to calculate abundance, and biomass of sturgeons using the swept area method. Catch per unit area (CPUA) in the winter 2006 survey was 3853 specimens nm2 , in the summer and winter 2007 survey was 1854 , 2912 specimens nm2 at depths less than 10 m respectively . CPUA for sturgeons in spring 2008 survey was 2103 specimens nm2 at depths less than 10 m and 393 specimens nm2 at depths greater than 10 m (10-100 m depth). These values in the winter 2008 survey dropped to 44 specimens nm2 at depths at depths above 10 m. CPUA for sturgeons in the spring 2009 survey was 300 specimens nm2 at depths less than 10 m and 307 specimens nm2 at depths greater than 10 m. In all the surveys conducted CPUA for A. persicus was higher than that for the other sturgeon species. Based on the calculations carried out in the marine survey in winter 2006 the estimated absolute abundance for sturgeons was about 2977.363 thousand. The total biomass of sturgeon was estimated as 131.713 tons. In the summer 2007 survey total abundance was estimated 1432.398 thousand, and total biomass of sturgeons was estimated at about 312.161 tons. In the winter 2007 survey total abundance for sturgeons was estimated at about 2250.105 thousand, and total biomass was estimated 578.08 tons. In the spring 2008 survey total abundance was estimated at about 3002.832 thousand. The total biomass was estimated at about 2533.318 tons .In the winter 2008 survey total abundance was estimated at about 152.722 thousand, and total biomass in winter 2008 was estimated 170.540 tons. Total abundance in spring 2009 survey was 1310.232 thousand and total biomass was estimated at 2019.tons. Investigation of stomach content of sturgeon Acipenser persicus caught under 10m depth in 2006 to 2007 surveys showed that there is significant difference in the consumed food. Polychaeta is the major food consumed and crustacean an the minor one(P〉0.05).Also no new types of food( such as bony fishes or benthic) have been observed in food chain of Acipenser persicus only the food consumption rate has been related to the season of year and increases or decreases in warm or cold seasons, respectively For physiological study and determination of sexual maturation stages in sturgeon,119 gonad sampling prepared. The results showed that 63 % of fishes were females and 37 % of them were males. Gill microscopic study shows complications such as hyperplasia, curvature, adhesion, embowed, shorting and lengthen of secondary filaments and fraught bloody. Microscopic study on liver indicates signs of cloudy inflammation, fatty degeneration, dispersion of billed secretions and cell atrophy. The population genetic structure of Persian sturgeon (Acipenser persicus) in Sefidrood and Gorganrood rivers watershed analyzed based on microsatellite markers during sturgeons assessment in 2006-2008. Results showed that Acipenser persicus in two region of south part of Caspian Sea are two independent populations.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Anzali wetland is one of the most important places for spawning fishes and zooplankton groups are the first consumer in this ecosystem . they are the perfect food for the larvae of fishes. Zooplankton status was evaluated in 6 stations of different areas of the Anzali wetland during March 2011 to February 2012. Sampling was done by tube (PVC) and passing through of 30 micron planktonic net. The samples were identified and counted by invert microscope. According to the results were identified 60 Genus and 6 phylum (11, 31, 10, 2, 1, 1, 1, 2 genus of phylum Protozoa, Rotatoria, Arthropoda, Gastrotricha, Mollusca, Tardigrada, Nematoda, Porifera, Annelida) respectively. The results showed that the maximum annual average density of zooplankton was observed with 2497 number per litre in Karkan station and the population was more in the summer than in other seasons. Phylum of Rotatoria,, protozoa and superclass Copepoda formed 48, 45 and 6percent of the density espectively. According to the results the populationof zooplankton did not change much compared to past studies, excluding Protozoa but the diversity of all zooplankton groupe are declined very much. According to the statistical analysis Kruskal Wallis are not significant differences between density of zooplankton in different stations, months and seasons (p 〉 0.05),but significant differences were found in different phylum together (p 〈 0.05).

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This survey was carried out in 8 lines of southern area of Caspian sea consisting of Astara, Anzali, Sefid roud, Tonekabon, Noshahr, Babolsar, Amirabad and Torkman in depths of 5, 10, 20, 50 and 100m in 4 seasons (spring, summer,autumn and winter) of the year 2008. The goal of this survey was identification of different species, distribution, density and Biomass of the zooplankton community in different regions and also their frequency in the different layers and depths and the population fluctuations in whole of year. The most abundance and biomass of the zooplanktons were 28005±24212 ind./m3 and 180.58±149.03 mg/m3in 5 min spring and they were reduced gradually to depths.Copepoda comprised between 9 to 16 percent, Rotatoria comprised between 5 to 13 percent and Lamellibranchiata larvae comprised between 27 to 70 percent of marin zooplanktons.The most abundance and biomass were 11746±7921 ind./m3 and 47.07±31.96 mg/m3, 5281±5521 ind./m3 and 29.03±31.68 mg/m3 in 5m of summer and autumn seasons, respectively. Copepoda comprised more than 95 percent of marin zooplanktons in all of depths in these seasons. The most abundance and biomass were 19030±16518 ind./m3 and 198.99±217.23 mg/m3 in 5 m in winter. Copepoda comprised between 17 to 49 percent and Rotatoria comprised between 32 to 70 percent of marin zooplanktons in all of depths and the abundance of other groups was not considerable in zooplankton community.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The project “Stock Assessment of Zobaidy, Pampus argenteus, in the North of Persian Gulf” started in April 2003 and completed by the end of April 2006 as a cooperative research project to assess the valuable stock of zobaidy shared between Kuwait and Iran in the North of Persian Gulf. The main objectives were to investigate and determine the basic biological parameters, the standing biomass, seasonal abundance, and the impact of regional fishery activities. These studies are necessary to recommend practical management policies and measures for long-term sustainability of the zobaidy stock. The sampling of fisheries data (catch, effort, fish length distributions, and biological data) was started in May 2003 and ended December 2006. Monthly length frequencies data were collected from both the drift gill net and shrimp trawl fisheries. Age determination was based on otolith sectioning, polishing, etching, and staining method. The age groups ranged from 0 to 10 yrs but the dominant age groups were 1-3 years and the estimated parameters for both sexes were L∞ = 32.0-36.0 cm FL and K = 0.26-0.30 yr-1, females grow faster than males. Sea survey on board of two dhow boats was carried out using swept area method. Higher abundance was always obtained in Kuwait Bay rather than the other areas surveyed in Kuwait and Khuzestan waters. The total estimated stock biomass in the surveyed areas varied from 42 t in January 2004 to 2,633 t in November 2004, while the Iranian biomass varied from as low as 19 t in October 2005 to 295 t in November 2003. The data indicated that Ras Al-Gaid, Bubiyan Island is the main nursery area in Kuwait waters, while Lifah, Busaif, and Bahrakan are important nursery areas in the Khuzestan waters. Kuwait Bay and Khor Musa are considered important spawning grounds and should be protected. Yield per recruit analysis showed that higher yield could be gained with increasing fish effort, which is not recommended under the present status of high exploitation rate. In contrast, virtual population analysis indicated that future catches will reduce if the fishery continues with present level fishing effort. A reduction of 50% would be required to maintain the present level of catches as well as to enhance the stock biomass. Formulation of a joint advisory management committee would be advisable approach to manage and monitor the zobaidy stock in the region. This will need commitment from the three countries in the region for data collection on regular basis on length frequency, statistics, and biological data. Copepods with high occurence of 64% - 88% is considered as the main item in the Pomfret fish, while jelly fish and other decapods crustaceans are considered as minor items. Observation of pre- flexion stage larvae of pampus genus among the specimens collected from Khuzestan coast water could be considered as an evidence for the spawning of this fish in this region. The occurrence of pampus larvae in Khuzestan coast during the months of June to October has been reported for several times. Examination of 101 specimens (38 from Kuwait, 63 from Iran) for molecular survey does not show any significant differences between Kuwait and Iran water stocks for this fish, so it is possible to hypothesize a unit population for zobidy stock in Persian Gulf and Oman Sea as whole.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The limnological study of the Golabar dam showed that in the Glabar dam inspite of bing its early establishmeant due to high nutrient and organic matter is located in eutrophic stage. the pH as well as bicarbonate levels shows that buffering capacity of the lake is high and the value of inorganic and organic matter measured are not considered as limiting factor for warme and cold water aquaculture.In the plankton survey 44 species of phytoplankton and 25 species of zooplankton were identified.Cyclotella , Nitzschia, Synedra and Trachelomona from phytoplankton and Polyarthera , Keratella , Filinia , Pompholyx from zooplankton were the dominant spicies.the Bacillariophyta from phytoplankton with 76.5 percent and Rotatoria zooplankton to with 76.2 percent considered the highest abundant . the average frequency of phytoplankton and zooplankton were 5*106 and 723 individual per litter. The Shironomide and Tobificide were the only two bentic group were identified in reservoir wehre their mean frequced were 293.75 and 224.30 respectively.The average biomass of bentic organism were 1.44±0.97 gr/m2.In the survey 12 species of fishes were identified.The potential natural production have been estimated to be 2.8 to 15.5 kg for bentivorous fish and varied from 53 to 175 kg /hec for plankton consumer fishes .The low temperature in several months as well as ice covered of the lake surface in particular in the months of duty and Bahman are the limiting factor of either warm or cold water fish production.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The ecological study of the Persian Gulf Martyres Lake carried out at the 5 stations between 2013 and 2014. This study identified 35 phytoplankton taxa. The diatoms taxa was dominated and their abundance recorded highest (2000 000 cell. l-1) in the lake. The annual phytoplankton abundance was measured as 2500 000 cell. l-1 during the study. The total nitrogen and water temperature were the significant a biotic parameters to increase cyanophytes abundance. Furthermore, 37 zooplankton taxa were identified. The Rotatoria abundance was dominated zooplankton. The annual zooplankton abundance was measured as 72 ind.l-1. Based on the CCA, there was no correlation between Rotatoria abundance and a biotic parameters. The study benthos showed Ephemeroptera and Diptera abundance were dominated; artificial bottom and lack of sediment and organic matters were the main reasons in decreasing of the benthos density. The Chitgar lake is the poorest lake in Iran due to low density of plankton and benthos organisms. The estimation of fish production was 123 kg/ha and for the lake was determaind 16 tonne. The finding display, invasive species was the main fish Chitgar lake that would be negative effect and increase eutriphication trend in the lake. Phosphorus parameter was limited parameters and trophy level recorded low due to high N/P ration in the lake. In overall the Chitgar lake situation is in Oligotrophic category with the low trophy level.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The distribution and stock assessment of edible bivalves were carried out in Bushehr shoreline areas (from 50֯ 38 - 29֯ 27 to 52֯ 41 - 27֯ 17 ) throughout the period of September 2008 - 2009. The objectives of this study were identifying the location of edible bivalves, biomass estimation, to estimate the growth parameters and natural mortality. Samples were obtained at roughly monthly or bimonthly from 7 areas and some of the at low tide during the year from 4 areas. Transects were selected at random direction and at the zigzag pattern in every area, so that is cover all of the shell beds. In each transects one or two sampling quadrat (0.25 m2) were placed randomly. Depending on the area size the number of the quadrat were different. After the removal of the stones and debries, the edible bivalves (empty and live bivalves) and some of the decoration shells were identified and numbered. Some of the samples were transferred to a bag and taken back to the lab for further identification and further analysis. In this study, the percentage of samples was used to show the distribution of the species in different areas. Faunal affinity between stations was calculated by Sorensen formula. For the purpose of the stock abundance, the mean number of the shells in each quadrat was regarded as an estimate of stock mean. The total stock in the investigated areas was obtained by multiplying the mean by the ratio of the stock area to the quadrat area (0.25 m2). Confident limits 0.95 % or 95 probility was given for precise the estimates. The length of some of the bivalves was measured from dextral to sinistral with vernier calipers to the nearest 0.1 millimeter. In some of the species the length frequency was used to estimate growth and natural mortality parameters. A subset of samples of Solen brevis was taken to the laboratory for the precise measurements, and relationship between body weights and total length. Surface sediment samples (5-20 cm) inhabited by some clam species were sampled in some areas. Water temperature and salinity were recorded during the survey in the sampled areas. A total of 45 species or species group was identified in the study area. The main area distributions for live edible bivalve, Solen brevis were located at Bupatil, Kaloo, Piazi and Bordekhoon. Other bivalve, Paphia cor was distributed in the Gassir, but empty bivalve shell was seen in the Bordekhoon shoreline. A limited tidal coastal area of Ganaveh has been covered by a pearl oyster species, Pinctada radiate that attached in the rocky beds. The empty shells of this species and other genus of the family were distributed in the other areas such as Golestan and Nayband. The most important areas for the decoration shells were located in the Golestan and Nayband. The empty bivalve shells, Trachycardium lacunosum were distributed in Lavar shoreline. The other species or species group were distributed in the shoreline of the study areas in different months with the low abundance. The growth parameters of two alive species, Paphia cor and Solen brevis were estimated. The Von Bertalanffy growth parameters for Paphia cor were estimated as K = 0.8 Year-1, L∞= 55 mm and t0 = -0.45 and for Solen brevis K = 0.7 Year-1, L = 120 mm and t0 = -0.35. . Estimated natural mortality rate for Paphia cor was M = 0.57 and for Solen brevis M = 0.26. The maximum ages (Tmax) calculated were 50 months for Paphia cor and 54 months for Solen brevis. The mean biomass of Solen brevis in Bupatil was 3.25 1.1 shells per quadrat with a maximum peak 4.6 shells per quadrat in October (Mehr) and minimum 1.5 shells per quadrat in Augest (Mordad). For the pearl oyster, Pinctada radiata in the Ganaveh this estimation was obtained in maximum peak in July (Tir) 60.5 shells per 100 m2 and minimum in March (Esfand) 3 per 100 m2. Mean biomass for this species was estimated 27.724.2 shells per 100 m2. The mean biomass of P. cor was 8.8 2.2 shells per quadrat and with a maximum in February (Bahman) and minimum in November (Abban).

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The Caspian goby, Neogobius caspius, is an endemic species of Gobiidae family in the Caspian Sea and it has ecological importance (as food for Caspian commercial fish such as sturgeons). The main aims of this study are, studying distribution, length, weight and age structure, sex ratio, diet, reproduction biology and morphological characters of this species in Guilan coast at waters of the Caspian sea and the sampling has been done monthly from Oct. 2005 to Sep. 2006 in 4 station from Astara to Chaboksar, with bottom trawl which had 12.5 meter length, 4.7 meter gape width and 2 mm mesh size in code end. The results showed N. caspius abundance is 9.82±11.93% of Gobiids and 7.92±10.10% of total fish numbers sampled in the study area (13824 specimens belong to 16 fish species) and there were significant differences among stations and seasons. CPUA of N.Caspius was estimated 52.5±105.9 ind/hec and 412.7±770.7 g/hec and there were significant differences among stations and seasons. Maximum body weight, total length and age were measured 65.10 g, 176 mm and 6 years old with an average 8.74±9.9 g, 84.83±28.4 mm and 1.83 years old, respectively and maximum age of males and females was 6 and 5 years old respectively and there were significant differences among stations and seasons and between sexes. It was estimated algometric growth model from length-weight regression, coefficient of K Von Bertalanffy growth model was estimated 0.42 and 0.68 in male and female, respectively. Sex ratio was 1.27 female to 1 male. Coefficient vacuity, relative gut length and intensity of 169 fullness were 8.72%, 0.76±0.17 and 267.7±263.3 for, respectively and Caspian goby fed on 30 different prey consist Zooplanktons (8 types), Benthic animals (15 types) and fishes (7 types) and young and yearlings have fed mainly mixed food (zooplankton and benthic animals) and adults on zoobenthose. Gammarids, Bivalvia, Cumaceae and Vormes constituted 44.7, 38.9, 24.8 and 19.7 % of prescence in full-gutted samples respectively, they were mainly preys (number and weight), hence this species is considered as euryphagus, carnivorous, benthphagus species. It was determined, Caspian goby spawns from March until last June, males and females take part in spawning in 2.8g and 65 mm and 1.3 g and 52 mm, respectively. Length at 50% maturity (LM50) was 80.2 and 77.5 mm in males and females, respectively. Maturity took place at 2 years old for both sexes, too. The absolute fecundity was estimated 109-1350 (451.6±216.3) eggs and relative fecundity 18-80 (36.8±9.2) eggs per one grams of body weight and diameter of ripe eggs was measured 1.31-2.60 (2.18±0.19) mm. Morphologically, there were 15 morphologically significant statistical differences between males and females and 15 differences among stations, sexual dimorphism was observed, too.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This project were investigated seasonally from march 2008 up to one year, in southern Caspian Sea iranian coast /Sampling was carried out at 8 stations of between 5 and 100 m depth and taken in triple with a 0/1m² van Veen grab/Total twenty four species and one family and one order were identified, presenting low dominance and frequency/ polychaeties 56%,oligochaetes 39% bivalves 〈1% amphipodes1% Cumacea and diptera and cirrepedia %1 of whole macrobenthos compositions/ Polychaetes and oligochaeta dominated, representing 95% of the whole fauna/Average of species were 11/8 species per grab/max 21 species / grab were found in Tonkabon stations at 100 meter depths and minmum 4 species/grab in 20 m in Bandar anzali /Maxmiun density were 4783 n/m^2 in spring and minmum 3177 n/m^2 in winter/Highest density were recorded in Amirabad stations and lowest in nooshar/ Maximum density showed in east, mimun in middle area of sea The biomass of benthos adventages in west/Average biomass of whole area were 6/932 gr/m^2/Mean total organic matter were 3/11±1/1 and silt- clay 62/92±6/12precent and Mean dissolve oxygen and salinity were 8/3±0/15 mg/l and salinity 12/2 ±0/4 ppm and water tempreture were 14/9±0/18ْC/ Mean grain size, fine sand, very fine sand, silt and clay contents were among the main factors related to the patterns of macrofaunal distribution, density and diversity and dominance of trophic groups.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was conducted to determine catch and fishing effort trends, length and age composition, growth and mortality parameters and estimate biomass and acceptable biological catch of Kutum in the Iranian coastal waters of the Caspian Sea from 2015 to 2017. The catch of Kutum was 4282.9 and 3395.5 tons and CPUE were 98.3 and 80.4 kg/haul in 2015-2016 and 2016-2017, respectively. The mean (± SD) of fork length were observed 38.8±6.6 and 37.1±5.6 cm and for total weight were 790.8±435.2 and 637.2±392.2 gram in 2015-2016 and 2016- 2017, respectively. The most predominated of length class was obtained 34-36 cm in 2015-2016 and from 36-38 to 38-40 cm in 2016-2017 respectively and frequency of immature individuals were observed 48.1 and 55.5 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 3 to 5 years comprised up to 76.6 percent. In length – weight relationship a, b and r2 were calculated 0.01, 3.04 and 0.96 in 2015-2016 and 0.005, 3.19 and 0.92 in 2016-2017 respectively. K value, L∞ and t0 were calculated 0.2 (/year), 62.3 cm and -0.65 respectively. Mortality parameters such as Z, M and F were calculated 0.72, 0.37 and 0.35 respectively and Exploitation rate were calculated 0.49. The biomass of kutum estimated 25270 tons and the biomass of Kutum decreased in recently years in spite of produce and release of huge fingerlings. This recruitment (produce and release fingerlings) must be continued for stability of stocks and fishing stress must be decrease by anyway.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The Sampling of macrobenthic communities in southeastern Caspian Sea, Iranian coast, were investigated seasonally from April to March 2012. Sampling was carried out at 8 transect as named Astara, Badar Anzali , Sefied rood , Tonekaboon , Nooshahr , Babolsar, Amirabad, Gomishan.In each transect were choice 8 stations at 5m, 10m, 20m, 50m, 100m depths respectively. Samples were taken in triplet with a 0.1m² van Veen grab.Totally 28 macrofaunal species belonging to 10 families were identified as gamaridae (9species), corophidae (3species),psudocumidae(8 species), amphartidae (2species), balanidae, chironomidae, cardidae scorbicolaridae, nereidae, sponoidae, each one species. Polychaetes were dominated, representing 72.5% of the whole fauna while while (equal 62.4% of total abundance and 5/1%biomass) were belong to Streblospio spp. from Spionidae family. Cerastoderma lamarcki belong to bivavia consist of 2/3% total macobethos abundance and 73% biomass. Total abundance of macrobenthos of middle area were higher than east and west area in southern Caspian Sea. Average benthic population density (no/m2) with (SE) was 4581(444 ). The benthic biomass (mg/m2) with an overall mean of 12. 125(02). Spatial and temporal variations of benthos. In the present study showed, maximum abundance Macrobenthos 17855(5543) no/m2 )were recorded in 20 meter depths at Nooshahr trancect , while minimum 841(109 )in 10 meter depths at Amirabad trancect p〈0.05. Maximum biomass 135.10(126) g/m2 were obtained at 10m depths in Astara minimum 0.51(0.4) ) g/m2 at 5m depths in Nooshahr transect . maximum were obtained in winter and minimum in summer Number of species varied 3 to 18 , Generally, minimum species diversity were obtained at 20 m depth in Tonekabon transects and the maximum value was observed at 100 m depth of sefeidrood variations physicochemical factors were between salinity 12.5to12.9ppt ,temperature 8-19˚c and PH 8.1 dissolve oxygen 69-101mg/li. Total secondary production calculated, according ,104/996g AFDW/m2/yr.Maximum were recorded in 10meter depth (30/381AFDW/m2/yr) and minimum at 50 meter depth(11/007g AFDW/m2/yr) respectively. Average total organic matter were 3/18 percent in sample periods. Percent of total organic matter (TOM) were low in 5 and 10 m depths and increased toward offshore depths. TOM percent was 1/67(0.11 )at 5 m depth and increased to 4/38(0.13 )in 100 m depth. Average total silt &clay were 68/63(2.97) percent in sample periods. Positive significant relation was between silt &clay and total organic matter. Macrobenthos community reduce in high silt clay and high sandy contents. Due to increase of streptolosbio.spp , monitoring program for understanding effect of this organism on ecosystem and on fish feeding is necessary.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: 0Genetic polymorphism by means of biochemical genetic markers using polyacrylamide gel electrophoresis system in four barbus fish species has been investigated. Species scientific name were Barbus sharpeyi ; Gunther, 1847 , Barbus grypus ; Heckel, 1843, Barbus xanthopterus ; Heckel, 1843 and Barbus esocinus ; Heckel, 1843.Sampling site and location were mainly in the rivers located in Khoozestan province such as Karoon and Karkheh rivers and the Dez dam. Different organs such as blood, muscle, kidney, eye and heart were sampled and analysed for the presence of tf, es, sod and pgm alleles. High polymorphism and presence of different alleles scored, but populations were not in the H-W equilibrium. Considring results, using current and avaiable genetic markers such as microsattelits is recommended for future works.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The Taham dam reservoir has been established in order to provide drinking water of Zanjan population as far as 15 km in a mountain region at 1900 meter altitude with a 317 ha surface area. This study was conducted on biotic and a biotic factors in order to recognize of aquaculture possibility within drinking considerations. The results showed the less abundance of phytoplankton with 2 million/l. where abundant of zooplankton was 266 /l. Bacillariophyta and Chlorophyta belong to phytoplankton and Rotatoria belong to zooplankton were dominated among identified plankton phylum. There were identified 45 and 32 genus of phytoplankton and zooplankton respectively. There were identified 5 groups of benthos that Tubificidae, Hirudina had the most frequency, and the biomass of benthos was varied from 1.1 to 23.7 g /m2. The ichtiology survey showed presence of 6 species in the lake that Alburnoides bipunctatus, Capoeta capoeta, , Leuciscus cephalus were the most abundance in the catch. L. cephalus was recorded with the maximum size of 870 g while the most frequent weight class was 150 450 g for C. capoeta,, L. cephalus . Diet survey showed the adequate feeding of fishes in lake also the observation of leech in trout guts was very considerable. The reproduction study displayed that a partial of matured fishes were succeed in breeding. Leuciscus cephalus have been known as a typical species with commercial size and high abundance which will be needed a fisheries management in Taham Lake to sustainable exploitation. The hidrochemical results indicated low nutrients values while total nitrogen was varied from 0.32 to 0.61 mg/l. and the Chl-a was varied from 7.9 to 25.9 μg/l.. The oxygen amount was 4.5 to 8.4 mg/l even in 65 meter depths. Total hardness average was about 149 mg/l where the Ca and Mn were measured in a low values. Trophic model in Taham lake showed the early stage of mesotrophy while other lakes and wetlands in north of Iran had been progressed in mesotrophic level.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study focused on identification phytoplankton, zooplankton, benthos, fishes and relationship between biotic and abiotic parameters at three stations in the Kan river during 2014. This study identified 19 phytoplankton taxa. The findings showed, the diatoms abundance were dominated in the river. The chlorophytes abundance were recorded the lowest abundance in this study. The nutrients and water temperature were the significant abiotic parameters to increase cyanophytes and chlorophytes abundance in the Kan river. This study identified 26 zooplankton taxa. The Rotatoria and Protozoa abundance were dominated in the Kan river. Based on CCA, there was no correlation between abundance zooplankton and abiotic parameters. The biodiversity index of plankton was between 1.8 and 2 and the lake situation is located in the mesotrophic category. The study of the Kan river fishes showed, only one endemic fish species Capoeta bohsei. The length (between 38 and 270 mm, average 144±86 mm) and weight (between 1.1 and 356 g, average 108.8±146.7 g) of the C. bohsei were varied during the study period. The 19 benthos taxa were identified. The Ephemeroptera was most abundant in the benthos groups. The classification of river based on biology indicator and environmental parameters confimed that water quality is located in the moderate category.

Description: Iranian Fisheries Science Research Institute

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Description: This study has been carried out in waters of Bushehr province in the Persian Gulf covering Nayband bay to Bahregansar between 26° 45 N to 30° 00 N and 49° 45 E to 52° 45 E, 15 main and 5 sub- stations, by R/V Ferdows 1 in winter 2004, summer 2004 and winter 2005. The physico - chemical parameters, nutrients (silicate, phosphate, nitrate and nitrite), phyto, zooplanktons, sediments and macrobenthoses were collected from water layers and sea bottom, and then analysed. The parameters were compared and evaluated with the results of the previous work, conducted in the same area. Termocline, halocline, oxycline and picnocline layers were formed in summer. These clins disappeared due to water column mixing in winter. The values of temperature, conductivity and pH in summer were higher than those of in winter, while the salinity and density values of surface and subsurface layers in winter were higher than those of in summer. The temperature and conductivity have been decreased from surface to depth, from coastal rigions to offshore and from southern waters to northwern waters, while salinity, density and turbidity have been increased. The dissolved oxygen is decreased by increasing the values of temperature, salinity and depth and it is observed that D.O. has increased in correlation with chlorophyl a in mean and subsurface layers. The pH was rather decreased from surface to depth while turbidity was increased. Orthosilicate (Si_SiO44), nitrate (N_NO3 ), and nitrite (N_NO2 ) concentration have increased from surface to depth while orthophostate (P_PO43) decreased. Among the phytoplanktons, Dinophycea had most abundance in winter 2004 and Diatoms had most abundance, variety and distribution in summer 2004 and winter 2005. Among the zooplanktons, Copeopda had most abundance, variety and distribution. The intensity of phytoplanktons in summer was more than those in winter; it decreased from surface to depth and from coastal rigions to offshore, at first increased and then gradually decreases. Intensity of zooplanktons in summer was more than those in winter and decreased from surface layers to depth and from coastal waters to offshore. The abundance of benthoses in summer was more than that in winter while their biomass in winter was more than that in summer. The abundance decreased from southern to northwern waters, but the rate of decrease in biomass was more than that of abundance. The mainly texture of sediments was loamy or muddy and the grain size in southeastern and northwestern areas were coarser than those in middle area. Compared with the previous study, the trend of physico chemical, silicate, nitrate and nitrite were the same but in spite of the past, the values of pH in summer were more than those in winter and also phosphate concentration had been decreased frome surface layer to depth. The overall trends of phyto and zooplanktons densities are almost similar to previous observation, but cyanophyceae significantly decreased, in comparison with spring and summer abundance. It is also observed that the zooplanktons average density has been in reverse order compared to previous observations. Average concentration of phosphate in the entire region was seven times more than that of the former study and its maximum value has rised more than 26 times in the petroleum and gas industries areas. On the other hand, the abundance and diversity of phyto and zooplanktons and also the ratio of biomass to abundance of benthoses were decreased.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Demersal resources in the Gulf of Oman are one of the main objectives for both industrial and traditional fisheries. In order to implement a rational management of these resources; the research project of “stock assessment of demersal resources in the Gulf of Oman” were carried out as a monitoring survey in 2003 The objectives of project were: 1) Identification of catches composition of demersal fishes 2) To estimate the biomass and CPUA of demersal resources 3) To determine the distribution pattern of commercial fishes 4) To determine the ratio of commercial, non-commercial fishes and amount of bycatches The studied area was restricted to the borderline with Pakistan in Gwatr (61 25 E) in the east and strait of Hormuz (57 00 E) in the west and isobath of 100m in the south, covering depths of 10 to 100 m with a total area of 1700 nm2. The R/V Ferdows-1, a stern trawler equipped with a fish bottom trawl was used for sampling. To collect the catch data, 107 stations were selected in a random stratified design distributed in different depths and area. The total area was stratified to 7 primary strata, and 4 different sublayers of 10-20, 20-30, 30- 50 and 50-100 m. The swept area method was used to assess and estimate the amount of biomass and CPUA (catch per unit of effort). The total catch was classified to 3 main groups of: a) The commercial demersal fishes, b) The non-commercial demersal fishes c) The non-demersal group The total biomass of all groups was estimated 88346 tons of which 52478 tons belonged to jellyfishes. In this year there was an unpredictable and high bloom of jellyfishes scattering in all area of the Gulf of Oman. The total biomass of fishes was estimated 35808 tons of which 19391 tons were commercial fishes. Meanwhile the amount of non-commercial fishes was calculated about 15102 tons.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This project in partnership with Azerbaijan State Fisheries Department and the aim of increasing fish production hydrothermal (Carp fish) at unit area through providing scientific and practical method in applying air device and nutrition management, a field area of 8.5 hectares and in ponds with 3300 m2 at village Eylarzgy carried at Urmia city. After preparation of ponds, action to release fry density was 6000 ha piece. Percent including 55 percent of silver carp (as most fish), Common carp 31 percent, 8 percent Grass carp and 6 percent of Big head with average weights 67 to 92 grams respectively. For fertilizing ponds in addition to basic fertilizer, during development, organic fertilizers (cow) amount to 24 ton/ hectar (Aslary) once every two days and types of mineral fertilizers (chemical) rate of 1012.5 kg per in three days once were used.In addition to feeding carp fish with natural food, concentrates and food for feeing Grass carp fresh forage (alfalfa) was used. Oxygen supply required for ponds were provided with one to two air units (Air jet). Sampling and biometry of fish and water samples for water analysis and identification of plant zooplankton (of the family and genus) once every month until the end of the growing period was performed. Resulting data were analyzed with Excel statistical software. Results showed that the production rate in the studied ponds was 4.74 tons per hectare and production of 3.15 tons per hectare in year ago, the farm has 50.5 percent increase compared to year ago average production rate in the whole province (3.21 tons per hectare) of 47.7 percent and the average production rate in the country in 1385 (about 3.8 tons per hectare) 24.7 percent increase shows.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In order to limnological study of Bukan Dam reservoir, sampling was performed monthly from determined sampling sites from April 2013 to March 2014. Sampling was conducted in reservoir lake by a PVC pipe with 2.25 m length and 5 cm diameter by columnar method. Besides, in more dipper (〉5 m) sites, sampling conducted from bottom to surface with 1-m intervals (layer sampling) by a 2-liter Ruttner type sampler. In rivers due to water flow sampling was conducted by a scaled measure. Phytoplankton sampling was performed by 1-liter bottles. Zooplankton was sampled by filtering of 30 L through 55- micron plankton net. These samples were then transferred into bottles and sampling date and the name of station were attached on the bottles. Then, the samples were fixed immediately and transported to laboratory. It should be mentioned some physical parameters were determined in situ. Also, a 2-liter and another 1-liter water were collected to determine chlorophyll a and chemical factors respectively. Samples were preserved in dark and cold place for a week. The upper layers (without phytoplankton) were removed and the lower layer (with phytoplankton) was sampled into 5-ml chambers. The enumeration and identification was performed by a Nikon TS100 inverted microscope with ×400 (Phytoplankton) and ×200 (Zooplankton) magnification according to Utermohl (1958) method. About 50 fields were enumerated for each sample. The comparison of physicochemical and biological factors with standard criterion indicated that the presence of a fertile plain, agricultural growth, drought and higher water demand in recent years, as well as, higher population density, the Saghez city which is the main source of pollution in Bukan dam reservoir has caused that Bukan dam is in the transit state from mesotrophy to eutrophy. The results of the present study suggested that higher trophy in Bukan dam reservoir together with algal high density has negatively affected the Fish life and has reduced the stock in the lake. However, complementary studies should be performed prior to releasing. In this way the problems of other ecosystems should be prevented.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: During the year 1998 1999 Mako and Mabhabad reservoirs were surveyed by Fisheries Research Center of Guilan province Mahabad Resevoir located at 36 47 N ( Lat ) and 45 , 43 E ( Long ) in western It has an average area of 700 hectares and is mesotroph- that Azarbiajan province chracterized by depletion of oxygen in the bottom during warm months In phytoplankton , Chrysophyta and in zooplankton Rotifera were dominance . There is low diversity of benthic animals in this reservoir and Oligocheata and Chironomidae are two benthic forms that comprise the most populations The fishes of this water body can be categorized in two groups : endemic and exotic . Ichthyofauna of the reservoir and its catchment area comprise 9 endemic species and subspecies and 9 exotic species and subspecies that located in 4 family , Cyprinidae , Balitoridea Siluridea and Poeciiiidae In the reservoir and its inlets and outlets , Cyprinidae is salient component of the ichthyofauna by a figure of 83.3 % . The fishes of this reservoir are ail kind of food zooplanktoniphagous level consumers such as phytoplanktoniphagous benthophagous and picsivorous Parasitic diseases are highly incident among the fishes of this water body and it can be said that fishes of the reservoir are widely infected by the parasitic diseases . The most important waterfowls and seashore birds are that migrate to the reservoir for wintering . The most commercially endemic fish species are Sia mahi ( Capoeta capoeta ) dace ( Leuciscus cepha/us ) and catfish ( Si/urus g/anis ) and commercially exotic species are common carp ( Cyprinus carpio ) Silver carp ( Hypophtha/michthys molitrix ) and Big head (Hypophtha/michthys The annual catch of endemic and exotic species in 1998 were 124 and nobi/is ) Stock estimation showed over exploitation and 111.9 tonnes respectively underexploitation for exotic ( big head and silver carp ) and endemic ( dace and sia mahi ) fish species respectively . Estimation revealed that this reservoir annually can produce 14323 tonnes of silver carp big head and common carp and for achiveing this figuer anoually 394000 fingerlings of mentioned species should be released in this Mako reservoir which is situatd on Zang Mar river was built in 1995 It is 12 Km to Mako city with the geographical identification of 39 11 N ( Lat ) and 49 29 E ( Long ) It is a earth kind reservoir that has a maximum depth of 77 m . The length of the barrier is 210 m and the upper and lower wide of the barrier are 10 and 350 m respectively Three river entred to the reservoir are Ghezet Chay , Emam Gholi and Dibak .

Description: Iranian Fisheries Science Research Institute

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Description: Regarding to monitor of demersal resources in the Persian Gulf and Oman Sea, and also biomass and CPUA estimation of them, a series of research cruises (5 cruises per year) were carried out by R/V Ferdows-1covering the area from 49 00 E in the west (Khoozestan provice) to 61 25 E in the east (Gwater) in a 5 years program form 2004 up to 2008 (no cruise in 2006). The study area was stratified into 17 strata (A to Q) of which 10 starta (A to J) were in the Persian Gulf and 7 strata (K to Q) were in the Oman Sea, covering the depths of 10-50m in the Persian Gulf and 10-100m in the Oman Sea. A total of 316 stations were randomly selected. The biomass and CPUA were estimated by Swept Area method. The comparison between two regions indicated that the percentage of density of demersal fishes in the Persian Gulf during years 2004, 2005, 2007 and 2008 were 3.3, 3.9, 2.3 and 2.4 times more than the Oman Sea and totally 70-80% of total biomass was calculated for the Persian Gulf. Also a comparison among 17 starta, the highest biomass was found for starta C & D in the Bushehr province waters. The amount of CPUA for both regions of the Persian Gulf and Oman Sea was compared and it was concluded that in years 2004 and 2005, the mean CPUA in the Persian Gulf was partially higher than the Oman Sea with 1.06 & 1.20 times more; and on the contrary for the next two years this value was higher in the Oman Sea with 1.3 times more. The highest CPUA of demersal resources for the Oman Sea belonged to the strata K & O for years 2004, 2007 and 2008 and for year 2005 was for L and strata. It can be concluded that the north-west of Oman Sea has the best condition of biomass of commercial and non-commercial species and the O stratum will be in the second ranking. With review the mean CPUA in different depth-layers for years 2004, 2005, 2007 and 2008, it was concluded that with increasing the depth, the mean CPUA is decreased in which the CPUA values in depth-layer 10-20m for these years were 8.3, 3.0, 2.1 & 1.6 times more than depth-layer 50-100m. The comparison of mean CPUA for 10 strata of the Persian Gulf showed that in years 2004 and 2005, the mean CPUA of demersal fishes in the Hormuzgan province waters was higher than in Bushehr province waters (1.2 times more). In total, the highest maen CPUA belonged to F (Naiband to Mogham) and G (Mogham to Farour) in Hormuzgan waters. On the contrary, in years 2007 and 2008 this value in Bushehr waters was 1.3 times higher than western part of Hormuzgan waters with the highest value in D stratum(Boordekhoon to Dayyer). Also the comparison of mean CPUA for different depth-layers, it was found that the mean CPUA has ascending trend with increasing the depth, with the highest value in depth-laer of 30-50m in which contains the 55-68% of total biomass. The lowest biomass is found in depth-layers of 10-30m. Totally, the minimum CPUA and biomass for both commercial and non-commercial species belonged to a stratum located in Khouzestan province waters and it was shown the over-exploitation of resources in this area. The comparison between commercial and non-commercial groups in both ecosystems , it was concluded that the density of commercial species was higher than non-commercial ones , and in all years the Persian Gulf indicated higher values than the Oman Sea.

Description: Iranian Fisheries Science Research Institute

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Description: Without industrial and urban development and their effects on marine ecosystem, due to high biotic potential, Khure-Mussa would be one of the productive coastal areas. Because of sensitivity and vulnerability to environmental changes this area are classified in sensitive ecologic area. This study was conducted to evaluation ecological health status in Khure-Mussa in the Northwest of Persian Gulf by using benthic indices. Twenty creeks in Khure-Mussa area were set up for study and sampling in four seasons from winter 2008 to autumn 2009. Monthly water sampling for physico-chemical parameters was done by bottle sampler and seasonal samples of surface sediment were collected by Peterson grab sampler (0.125m2) .At each station three samples for macrobenthic study and one sample for grain size analysis and organic matter determination were obtain. Totally, 187589 macrobenthic individual were collected and separated. Among identified groups, Polychaetes with total number108906, Crustacean with total number 46561, Bivalve with total number 14156 and seapen with total number 9841 were the dominant groups and were included 58, 25, 8 and 5 percentage of total number respectively. The highest abundance in the spring and the lowest abundance in the summer were observed. According to mean abundance, Somaily creek and Khure-mussa (3) station showed the highest and the lowest abundance respectively. Seapen is included more than 90 % of total biomass. The range of Shannon diversity index was (1.95-3.58) which the minimum and the maximum values were found in Shipping and Patil station respectively. Significance benthic biological parameters (abundance and richness) in different creeks explained the variation of benthic community structure in studied creeks. In addition, seasonal significant differences were found in these parameters due to seasonal changes in benthic animal s succession. The results of grain size analysis showed that the range of siltclay was (63.6-95.59). According to AMBI index values, all of the studied creeks are classified in slightly pollution level and disturbed condition except for Petrochemical station that placed in moderate pollution level. The BOPA index values in all stations showed more than threshold level (0.19) that means bad and weak ecological condition. The highest and the lowest ITI index values were observed in Oil exporting port station (64.92) and Ghazaleh creek (29.53) respectively. The others were grouped in 30-60 range that means moderate pollution level and disturbed ecological status. The values of ABC (Abundance Biomass Curve) that explained the relation between macrobenthic biomass and abundance, were calculated near zero from 0.1 to -0.1 in all studied creeks that show moderate condition for living animals. In general the studied creeks showed pollution potential and benthic biological parameters indicated downward trend in ecological quality and health status.

Description: Iranian Fisheries Science Research Institute

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Description: Cheshmehkileh River and adjacent mountainous streams, play a strategic role as a historical axis for anthropogenic civilization, human welfare also habitat and migration pathway of commercial – biologic valuable fishes e.g. Caspian trout, Caspian kuttum, members of Cyprinidae family in south Caspian Sea drainage. Treats such as overfishing of Caspian trout and Red spotted trout stocks in mountainous headwaters, barriers construction and manipulations those are out of river carrying capacity developed by human activities, affected normal function of river as well. Sand mining big factories establishment next to the river, legal and illegal trade of river sediments, direct entry of Tonekabon landfill leakage into the river, development of Rainbow trout farms since 3 decades and huge effluents into the river containing dead fish and types of solids, escapement of cultured Rainbow trouts into the river, … are major minimum factors which needs basic information for integrating inclusively drainage management system. Cheshmehkileh River contains Headwaters of Dohezar (Daryasar & Nusha), Sehezar and Valamroud rivers during 13 monthly sampling phases between September 2009 and October 2010 based on macrozoobenthoses investigations by EPT, EPT/C EPA protocols, measurements of nominated physic-chemical and microbiologic parameters. Probability of Rainbow trouts escapement and invasion, existence, nutrition in Cheshmehkileh environment indeed investigated. Data analysis explained significant differences (P〈0.05) between groups of measured parameters in different sampling stations. Dendogram of clustered analysis based on consolidation of major biologic/ physic-chemical and microbiologic parameters, separated stations No. 1, 3, 2, 4 in one group and remained classified in different groups. Station 8 and 9 similarly separated which expressed general similarities according to Sehezar river environment which were differs in comparison with other stations. Station 11 separated according to its natural quality of water and environment. Similarities between station 10 to Sehezar river stations 8 and 9 expressed general influence of Sehezar River more than Dohezar River in Cheshmehkileh condition especially in station No. 10. High scores of EPT and EPT/C indices in upstream stations 1, 3 and 8 also low score of indices in stations 7, 13 and 6 expressed levels of environment quality between these groups of stations. Maximum average biomass of macroinvertebrates belongs to Trichoptera order in Cheshmehkileh River. Significant decrease of biomass in stations 11, 12 and 13 in comparison with other stations stated environment degradation in mentioned stations relevant to excessive sand mining as well. Pollution resistant groups of invertebrates significantly increased in downstreams against upstream stations. Also disappearing of Plecoptera order in station No. 7, 9, 10 and 13 stated low quality of environment in comparison with upstream stations. Confirmation of effects quality and quantity for point and non-point sources of imported pollutants require specific management considerations in order to present exploitations, pollutants control and emergencies for river monitoring in forthcoming years.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: From June 2004 to March 2006, a survey in Iran waters (Bushehr province) has completed. Sampling was accomplished in two area, north and south. In this period 15 cruises achieved in summer and 3 cruises in autumn and winter. In each cruise of north and south area 18 and 30 stations were sampled respectively. Stations row on three depth stratums that is, below 10 m, 10-20 m, and 20-30 m in total area from Bahrekan to Motaf. Some Biological parameters such as sex stages, sex ratio, mean total length, species composition were measured. Duration of shrimp fishing season in years 2004, 2005 and 2006 were 40, 44 and 40 days in summer respectively. In June and august the Catch per Unit Effort (CPUE) in south was more than northern area. CPUE increases in north area especially at the end of summer during fishing season gradually. Computing on Biomass estimation resulted 674, 1024 and 873 ton in years 2004, 2005 and 2006 respectively for all shrimp species (usually tiger shrimp, white shrimp and other). Total commercial landing of shrimp catch in above years were 1602, 1597 and 1110 ton respectively. Percentage of tiger shrimp in commercial landing in above years was 77, 75 and 84 respectively. We found that the least mean length of tiger shrimp was observed in southern area especially from Motaf to Rodmond stations. The schools of prawn penaeus semisulcatus enter to Bushehr waters from southern area that is Motaf region. Other than Motaf; Nakhilu, Rase khan and Rod-mond show same characteristics. Also in this region, density of shrimp increases with depth in most summer cruises. The result from analyses of gonad maturation studies shows the adult and mature females (stages III and IV) of P. semisulcatus accumulate in northern area at the end of autumn. This stock catches in autumn by illegal fishing.

Description: Iranian Fisheries Science Research Institute

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Description: The phytoplankton, zooplankton, Macrobenthos and ctenophore Mnemiopsis leidyi with Physico-chemical parameters and pollutants of water were investigated in the Caspian Sea during 2007-2008. The sample station located between 48°to° 54° longitude and 36° to 39° latitude. The samples were gathered in four seasons and eight transects (half-line perpendicular to the coast) in Astara, Anzali, Sefidrud, Tonekabon, Noshahr, Babolsar, Amirabad and Turkmen. Sampling was done of 5, 10, 20, 50 and 100M depth of different layers. Nonparametric test and multivariate analysis (PCA) were used for statistical methods. Physico-chemical factors: The results showed that the changes of physico-chemical factors, includes: water temperature, salinity, organic nitrogen and inorganic nitrogen (ammonium) are most important than other factors. The lowest sea surface water temperature was recorded in winter (7.2 oC) and highest in summer (29.8 oC) (p〈0.05). However, there was not significant difference at 50 and 100m depths in different seasons (p〉0.05). The lowest salinity was recorded in winter (10.42±0.14ppt) (p〈0.05) and the rest of the seasons, there was not significant difference (p〉0.05). The most inorganic nitrogen was determined (ammonium ion: 40.8±2 µg.l-1) in winter and the highest organic nitrogen (660.6±92 µg.l-1) in summer (p〈0.05). The concentration of inorganic nitrogen was evident from the surface layer to a depth of 100 meters (p〈0.05), but this trend was not observed in inorganic nitrogen (p〉0.05).The maximum concentrations of total nitrogen were measured at the near-shore stations (640.6±28 µg.l-1). The annual average water transparency was 4.91±0.24 m and increased in away from the beach (p〈0.05). Phytoplankton: in total, 191 species of phytoplankton were identified. The phylum of phytoplankton include: Bacillariophyta with 97 species (50.8%), Chlorophyta with 28 species (14.7%), Pyrrophyta with 26 species (13.6%), Cyanophyta with 25 species (13.1%) and Euglenophyta with 15 species (7.9%). Bacillariophyta and Euglenaphyta were had the most (51.49%) and the lowest (0.39%) abundance respectively. Nevertheless, Pyrrophyta and Chlorophyta were having the most (53.14%) and the lowest (0.54%) biomass respectively. Mean abundance and biomass of phytoplankton in the photic and the aphotic layers were a significant difference (p〈0.05). The average abundance and biomass decreased with increasing depth (p〈0.05). The most abundant and biomass phytoplankton was determined in the photic layer. Abundance and biomass of phytoplankton in the different seasons have been significant differences (p〈0.05).The most abundance of phytoplankton was in winter, fall, summer and spring respectively (p〈0.05) and the most biomass of phytoplankton was in winter, fall, spring and summer respectively (p〈0.05). Zooplankton: Also, 14 species of zooplankton include: 2 species of Copepoda, 5 species of Rotatoria, 2 species of Protozoa, 3 species of Cladocera, 2 species of newborn and larvae of Balanus and larvae of Bivalvia from meroplankton group were identified. However, the dominant zooplankton population was divided into three groups of copepoda, Rotatoria and meroplankton. Mean abundance and biomass of zooplankton in different seasons and layers showed significant different (p〈0.05). The most abundance and biomass of them in winter and the photic layer was determined. The mean abundance of Rotifera, Cladocera and protozoa in different depth was having not significant differences (p〉0.05). However, there was significantly in other groups (p〈0.05). The most abundance of them was in photic layer. Ctenophore: Average abundance and biomass of Mnemiopsis leidyiwere recorded 63±7 ind.m-3 and 7.70±2.34 g.m-3, respectively. The maximum seasonal average of abundance was 150 ± 17 ind.m-3 while the maximum biomass was 26.59± 4.61 g.m-3 in summer (p〈0.05). The lowest seasonal average of M. leidyi abundance and biomass were in the winter (6±2 ind.m-3 and 0.07±0.02 g.m-3, respectively) (p〈0.05).The average annual abundance and biomass of ctenophore were not significant difference in the 8 transects (p〉0.05). The maximum of ctenophore abundance and biomass were belonged to the depth of low than 20m (p〈0.05). The maximum of ctenophore abundance and biomass were recorded in the 5m depth of Anzali with 639 ind.m-3 and 158 g.m-3, respectively. Results of biological and non-biological factors showed that significant changes between euphotic and aphotic layers (p〈0.05).There were the most seasonal changes in the euphotic layer. The results showed that the presence of ctenophore is highly related to the presence of the zooplankton and phytoplankton and some non-biological factors. The water temperature is a limiting factor in the ctenophore Fluctuation at the winter, because of food presence (phytoplankton, zooplankton and Nutrients), M. leidyi have had the lowest abundance. Macrobenthos: Three phyla of macrobenthos (arthropoda, annelida and mollusca) include: 5 classes (crustacea, insecta, polycheata, oligocheata and bivalvia), 8 orders, 11 families, 26 genera and 24 species were identified. The most abundance and biomass of orders in the different seasons were belonged to polycheata (annual average: 2452±258 g.m-2) and bivalvia (annual average: 25±6 g.m-2), respectively. Macrobenthic abundance in all orders except insecta and oligocheata in different seasons was significant difference. The amount of seabed total organic mater (TOM) from the 5m to 100m stations was with an increasing trend and the highest percentage had in the 50m and 100m stations (P〈0.05). The percentage of seabed TOM was not significant difference in the different transect (P〈0.05). However, seabed grain size had significant difference (P〈0.05) and seabed grain size from the 5m to 100m stations was with a decrease trend in the size (P〈0.05). Macrobenthos and physicochemical parameters of correlation matrix showed that macrobenthos abundance in the between parameters have a positive correlation with TOM. However, it biomass with pH (positive), inorganic phosphorus (positive) and organic phosphorus (negative) have a correlation. Heavy metals: The levels of heavy metals (Cd, Cr, Cu, Fe, Pb, and Zn) of water had lower than standard and acceptable for aquatic life. Significant accumulation of metals such as Co, Cu and Cr in the sediment was observed at transect Sefidrud and Anzali and Ni at transects Sefidrud and Astara in comparison with six other transects (P〈0.05). Petroleum compounds (16PAHs): Concentration levels changes of petroleum compounds in seawater in different seasons was significant (P〈0.05) and in seasons of spring, summer, fall and winter was 56.5, 9.3, 14.9 and 19.3 of percent respectively. However, the concentration values in sediments of the sea in different seasons and transects were not significant difference. Maximum concentrations in summer and in Astara transects (8.02 mg.kg-1) were determined. In correlation matrix, observed positive correlation between petroleum compounds and Cr, Ni and Pb in sediments of seabed and between petroleum compounds and Zn in seawater. Organochlorine pesticides (OCPs): The OCPs concentration of seawater in different seasons had significant difference (p〈0.05). The pesticides groups of DDT, BHC, Drin and Endosulfan in seawater in different seasons had significant difference (p〈0.05), but, it was not found in Heptachlor group (p〉0.05). The maximum concentration values of OCPs in all groups in seawater were determined in winter (99%) (p〈0.05). The seawater OCPs concentration in comparison of regional and stations were not had significant differences (p〉0.05). The only DDT group in the seabed sediment had significant difference in different seasons (P〈0.05) and the maximum of seasonal average, it was determined in summer (Average: 0.88±062 mg.Kg-1 and Max: 4.5 mg.Kg1). However, in comparison of regional were not had significant differences (p〉0.05). In correlation matrix, the groups of Endosolfan and Drins in seawater and sediment were had equal variance and the changes were included. There was high correlation of between Endosulfan and Drin with DDT group in seawater and with Heptachlor group in the sediment of seabed. Surfactant: Mean surfactant concentration (LAS) between different seasons had significant difference (P〈0.05). The maximum concentrations of LAS were in spring and summer (Anzali transect) was 0.084 mg.l-1 and 0.082 mg.l-1, respectively. Also, average concentrations in the spring: 0.06±0.003 mg.l-1, summer: 0.059±0.004 mg.l-1, winter: 0.042±0.003 mg.l-1 and fall: 0.031 ± 0.013 mg.l-1 was determined. Nevertheless, there was no significant difference in the study area and station (p〉0.05). Based on existing standards, Surfactant concentration in the southern Caspian Sea region was not critical.

Description: Iranian Fisheries Science Research Institute

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Description: Comb jelly Mnemiopsis leidyi investigation was conducted in the southern region of the Iranian coast of the Caspian Sea during the 2010 in the seasons of spring, summer, autumn and winter at 8 transect with depths of 5, 10, 20, 50 and 100m. Sampling was done at 0–5, 0-10, 0-20, 20-50 and 50–1000 m using a 500 µ and 50 cm mouth opening area. During 2010, a total of 757 samples of comb jelly were collected by the size length of smaller than 5 mm to a maximum of 35 mm. Mean annually Mnemiopsis abundance and biomass was 11±2 ind.m3 and 0.6±0.1 g.m3 . Maximum abundance was recorded in autumn with 25.7±4.8 ind.m3 and maximum biomass was observed in summer of 1.2±0.1 g.m3 . Minimum abundance was found in spring with 2.3±0.4 ind.m3 and minimum biomass was in winter of 0.1±0.3 g.m3 . Statistical comparison showed that the density of comb jelly were not significantly different in spring and summer (P〉0.05, Tukey test), and winter and summer with the same density, while having the highest density of autumn compared to other seasons which showed a significant difference (P〈0.01, Tukey test). Comb jelly biomass showed summer and spring with higher than winter and autumn, compared to the statistical comparison showed no significant difference in biomass between seasons of summer- spring and fall – winter (P〉0.05). Fluctuations of comb jelly abundance and biomass in different seasons showed that the water level of 20 m had a higher value than other layers. In the spring, more than 98 percent of the comb jelly was recorded in the upper layer (less than 20 m), and only 2 percent of the animals living in layers of 20-50 m. In the summer and autumn, about 93 percent of Mnemiopsis was found in the layers above 20 m and 7 percent of those in the lower layers (maximum 50 meters). In the winter, more comb jelly were observed in layers from 20 to 50 m (about 14 percent) and about 87 percent of them were collected in layers less than 20 meters. As a whole, the total maximum annual average abundance was recorded in the autumn of layer 0-5 m with 94.0± 33.8 ind.m3 and the highest average biomass in the 0-5 m layer of summer with 3.1±1.0 g.m3 . Frequency of group length (size) of the population M. leidyi showed that comb jellies of less than 15 mm (prior to adult) consisted of 85.8%, in which at less than 20 m, group length (size) of 15 mm included of 82-92% and at the depth of more than 50 m, these group was 8-18%. Also comb jelly adults (greater than 16 mm) in the surface layers (less than 20 m) were included of approximately 73 to 100% and below 20 m, 0-27 % of the population. Data of the 8 transect showed that the highest density and biomass of Mnemiopsis were recorded in Torkaman with 16.4± 6.5 ind.m3 , and 0.8±0.2 g.m3 , respectively. Statistical comparison of the mean abundance and biomass of comb jelly showed that there were a significant differences between Turkmen and Amirabad transect compared to other transects (P〈0.05). Regional distribution of M. leidyi in the southern Caspian Sea showed aggressive area in terms of density and biomass are areas with significant differences (P〈0.05). Comb jelly population showed that both West and East in terms of abundance and biomass were similar but different with the central region. Eastern and western regions compared to the central region have the higher abundance. Based on the study looks at the rise and persistence parameters of comb jelly, it seems two main factors such as water temperature to the desired value, especially in summer (22-30°C), and food availability (zooplankton) have more roles in the southern of the Caspian Sea. After the invasion of M. leidyi into the Caspian Sea, not only the abundance and biomass of zooplankton decreased but also the species diversity decreased from 36 to 15 species. Hence, it seems the decline in the South Caspian comb jelly was due to decreased of fecundity for lack of zooplankton feeding resources.

Description: Iranian Fisheries Science Research Institute

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Description: This study was conducted to determine growth parameters, catch and fishing effort trends, stock assessment and Acceptable Biological Catch (ABC) of bony fishes in the Iranian coastal waters of Caspian Sea in the years 2013-2014 and 2014-2015. According to the result, the numbers of beach seines were 124 and 120 and their fishing efforts were observed 44688 and 46299 beach seining, respectively. The total catches (including illegal fishing) were also obtained 17144.3 mt and 16733.2 mt during 2013-2014 and 2014-2015, respectively. The highest proportion of catch was belonged to kutum and golden grey mullet (94.4% and 89.5%, respectively) in two fishing seasons mentioned above. Growth parameters of kutum were estimated as K=0.19/yr, L_∞ = 61.3 cm, t0 = -0.99/yr. The Growth parameters were K=0.18/yr, L_∞ = 61.1 cm, t0 = -0.14/yr for golden gray mullet and were K=0.14/yr, L_∞ = 70.8 cm, t0 = 0/yr for common carp. Based on catch-at-age data, in the years 2013-2014 and 2014-2015, the total biomass, from the biomass-based cohort analysis were estimated 46900 mt and 41000 mt for kutum and 11550 mt and 12670 mt for golden grey mullet, respectively. The reference points of F0.1 and F35% were 0.41/yr and 0.34/yr for kutum and 0.36/yr and 0.33/yr for golden grey mullet, respectively. According to catch of species/groups, three main groups can be divided easily. The one–way ANOSIM catch similarity test indicated that coverage rates of different years were homologous and similar, but the coverage rates of different months, regions and periods were not similar. Also, there were significant differences in community composition of fishes in catch of beach seines among three times; three durations; three regions and seasons (in all cases MRPP, p〈0.001). During 1996-2000 species Rutilus rutilus, Vimba vimba, Chalcalburnus chalcoides, Aspius aspius,Barbus sp, Salmo trutta caspius and Silurus glani in the years 2000-2005 species/groups shads, Abramis brama and Esox lucius and in the years 2005-2012 species Cyprinus carpio and Stizostedion lucioperca were indicator species. Also, in the west region of the Caspian Sea species/groups Vimba vimba, Chalcalburnu schalcoides, Aspius aspius, Barbus sp, Abramis brama, Stizostedion lucioperca, Esox lucius and Silurus glani; in middle Rutilus frisii kutum, shads and Salmo trutta caspius and in east species/groups mullets, Rutilus rutilus and Cyprinus carpio were identified as indicator species. Based on available models, the ABCs were estimated as 8250-9750 mt for kutum and 1650-1950 mt for golden grey mullet (with precautionary approach 8250 mt and 1650 mt for kutum and mullet, respectively). For two species, the ABC with a lower and more accurate value based on more information, should be selected for the implementation of a precautionary management approach.

Description: Iranian Fisheries Science Research Institute

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Description: Anzali wetland at south west of Caspian located along of North West and southeast and with its unique feature were add on the Ramsar convention list in 1975. There were recorded a high rich of fauna and flora including 276 plant species, 23 reptiles and amphibians, 60 fishes, 26 mammals and 195 birds. Anzali wetland were encountered with numerous disorder with the eutrophication and the early dismissing. The first studies on Anzali wetland started by many international institutions in 1964. In this study the data of biotic and abiotic factors in Anzali wetland analyzed which belongs to different sites (15 to 38 stations) during 1991 to 2000 and were sampled seasonally or monthly in different years. The results showed the increasing trend of phytoplankton abundance from 7.9 to 66 million C./l. and the western part had the most abundant. The Cyanophyta had the most development than other 7 phylum observed in the area. In Anzali wetland identified 143 phytoplankton genus that 9 genus dominated in more than 80 % replicates and 7 genus had the abundance of more than 5 million cell/l. The Zooplankton abundant increased from 580 to 2200 ind./l. The Rotatoria had the most abundant followed by Copepoda. There was identified 104 zooplankton genus that 5 genus were dominated in more than 80 % replicates and 11 genus had the abundance of more than 30 ind./L. The chlorophyll a varied from 8.8 to 50.2 μg/l. and had a increasing trend after 1996, meanwhile it was measured higher than 25 μg/l in most of the stations. The results of benthic study showed that the Chironomidae and Tubificidae were observed more than other organisms which comprised 12.2 to 23.5% of total biomass of benthic organisms in studied period. The range of biomass was 1.1 to 7.8 g/m2. The ichthyologic survey showed presence of 60 species that 11 species were exotic. 28 species belong to freshwater, 17 species were anadromous and 8 species were resident in estuary. The highest and lowest fish catch were 640 and 288 ton in 1994 and 1999 respectively and it was about 500 ton at the end of period. The hydrochemical factors had the various fluctuation so that the nutrients parameters had a significant difference over studied period. Total nitrogen was varied from 0.78 to 1.41 mg/l and total phosphorus varied from 0.05 to 0.1 μg/l.. The oxygen dissolved amount was from 4.6 to 8.7. EC was between 3 to 5 ms/cm during September and October that indicated of Caspian water projection. According to geographic position of station, all biotic and abiotic data, were arranged. The data bank is used by Idrisi software to produce of necessary maps. Analysis of data showed that there must be a responsible department with a vast authority. Conservation and eutrophication prevention of Anzali wetland connect to special attention to catchment area and landuse management of the wetland. Also there is an urgent need for well-developed technologies and managements to reduce the organic pollution and its environmental impacts on the Anzali Lagoon.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In this investigation which had been done in commercial catch regions (where discharged theirs catch) in three ports Babolsar, Amirabad (in mazandaran) and Anzali (in Guilan).The main objectives of the present study were to estimate of catch and catch per unit effort, von Bertalanffy growth parameters, condition factor, sex ratios, spawning, biomass and maximum sustainable yield of common kilka in Iranian waters of the Caspian Sea. The result shown that catch of kilka in Iranian coastal in 2015 increased from 21553 ton to 22428 ton in 2016 and CPUE was 2.6 and 2.7 ton (Vessel ×Night) respectively . Common kilka was the predominant all months of the year about 98 percent. The mean length was 103±9.6 at the same time and range length 92.5–112.5 mm were the dominant population (about 82%). The mean condition factor was 1.38±0.1 . Age abundance during this period have not been substantially changed and always fishes with 3 and 4 year olds had the highest frequency78.5 and 76.8 percent respectively. The parameters of the Von Bertalanffy growth curve were 138[1 exp ] 0.251( 1.124)   t Lt for common kilka. The instantaneous coefficient of natural mortality (M) was 0.506 yr-1 . The instantaneous coefficient of fihing mortality and total mortality were 0.753 yr-1 and 1.259 yr-1 , respectively. The exploitation rate of common kilka were 0.60 during 2015-2016. In the years 2014-2015 and 2015-2016, the biomass of common kilka was estimated 86401 and 71671 ton, respectively. In these years, fish of the 2nd and 3rd year of this fish had the highest amount of reserves (respectively 29025 and 24632 ton) and The lowest reserves for 6-year-old fish, respectively, were 772 and 355 tons respectively. The breeders biomass of this species is 37132 and 34390 tons respectively and The ratio of biomass of broodstocks to the whole was 43% and 48% respectively. Acceptable Biological Catch was estimated with a precautionary approach of 18,400 tons. The average catch of this species on the coast of Iran in the last 10 years has been more than 21,000 tons, and in fact, the optimal level of harvesting from the reserves has not been observed. It should be noted that when exploiting a storage facility, excessive harvesting of the harvestable product will lead to the destruction of longterm storage.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The main objectives of the present study were to estimate of biomass and maximum sustainable yield of common kilka in Iranian waters of the Caspian Sea. This paper examines the maximum sustainable yield (MSY) and fishing intensity at MSY (fMSY) and then using by fMSY, yield-per-recruit and spawning biomass-per-recruit under various harvest strategies of Fmax, F0.1 and F40%; the acceptable biological catch (ABC) was estimated. The results showed that the catch of three species of kilka were 24080 and 22969 t in 2012-2013 and 2013-2014 in Iranian waters of the Caspian sea, respectively and common kilka predominated with 98.1% and 98.9%, respectively. Growth parameters were estimated as L∞ = 141.8 mm, K=0.297 year−1 , t0 =−1.048 year−1 . The ages of common kilka comprised 6 age groups, ranged from 1 to 6 years and Age groups 3 and 4 years old had the highest frequency. In the years 2012-2013, the catch of age 1 and age 4 represented the lowest and highest proportion of total catch (133.6 and 9121.6 t). In 2013-2014, followed the catch of age 1 and age 3 had the lowest and highest proportion of total catch (151.9 and 8700.2 t). The instantaneous coefficient of natural mortality was estimated as 0.506 year−1 and total mortality and the instantaneous coefficient of terminal fishing mortality were 0.894 and 1.40 year−1 respectively. In the years 2012-2013 and 2013-2014, the biomass of common kilka was estimated 90700 and 83300 t, respectively. Also, the fishing mortality was 0.622 and 0.894 year−1 and the exploration rates were 0.551 and 0.636. The reference points of common kilka at F0.1 and F40% were estimated 0.92 and 0.80 year−1 , respectively. According to Schafer model the MSY and fMSY were estimated 22670 t and 8690 vessel×nights (a unit of effort). In 2013-2014, the ABC of common kilka was estimated 17500, 20060, 23500 and 18900 t in tiers 2, 3, 4 and 5, respectively. However, for the implementation of a precautionary management approach the lower and more accurate ABC-value, based on more information, should be selected and thus the catch should be restricted to 17500 t.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Limnological factors of brackish water pounds of the rainbow trout, Onchorhynchus mykiss were studied at Bafgh region in Yazd province. Physicochemical factors, phytoplankton, zooplankton and benthic populations of pools, supply and drainage channels from different farms were studied in aquaculture cycle in 2002 and 2003. Means were compared using Tukey HSD and t tests. Meanings of factors in 2002 and 2003 were respectively: and 9.3 0.2ppt; dissolved oxygen 7.9 0.2mg/l water temperature 13.8 0.3°c and 14.9 0.6°c; salinity 12.3 0.2ppt and 7.2 0.1mg/l; pH between 7.8 to 9.2 and 8.1 to 9.5; depth of hyalinity 0.85 0.1m and 1.1 0.1m; ammonium 0.1-0.5mg/l; and nitrate 1.8-21mg/l. Main phytoplankton were diatoms specially Chaetoceros, and Cyanophyta. Rotifera were the dominant zooplankton. Benthic fauna mainly included immature Chironomids. Final mean lengths were between 24.7cm to 31.5cm, mean weights between 11179.9gr to 434.6gr. FCR between 1.16 to 1.6; DGR between 1.04gr/day to 3.03gr/day; production 0.03kg/m2 to 0.84 kg/m2. Supply channels had the optimum limnological condition for trout aquaculture. Limnological factors were often not significantly different between pools and drainage channels. Saeeid and Rangin-Kaman farms were the most successful farms.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Intensive culture of rainbow trout, usually done using several different methods.The objective of this study was to compare fish performance and welfare in a new design of Foster-lucas ponds (FLP) and a raceway ponds (RP) under field conditions. Currennt study was designed in two treatment with three repeats. Each pond was randomly stocked by rainbow trout fish with initial average weight of approximately 51±5 g. Stocking density was 120n/m3 during study. After 10 months of trial, fish fed diets with comertial diet (Chineh Company). Feeding operation conducted according to the manuals by consideration of water temprature, fish waight and biomas. During the 10 months experiment, the fish survival rate was high (97.39 and 98.05%). No significant differences in growth parametres were observed between RP and FLP, but in all parametres FLP was higher than RP Final weight was 0.99% higher in FLP than in RP. Water quality factors (Dissolved oxygen, PH) was better in FLP. The results confirm that when water quality is maintained in safe level ranges, growth rate of rainbow trout attained in FLS are comparable to those in RP.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This project was designed with for objective on estimation of Biomass and optimum time for catch season of P.merguinsis and M.affinis shrimps. This investigation was carried out monthly by swept area method in coastal waters of Hormozgan province. The optimum time for fishing season in Bandar Abbas to Sirik waters in 2004,2005 and 2006 respectively was about 25/9/2004, 24/9/2005 and 25/9/2006. Total allowable catch ( T.A.C.) for P.merguiensis and M `.affinis estimated in 2004 to 2006 were 600 , 170 tonnes , 850 , 550 tonnes and 650 , 400 tonnes respectively. The densest catch was obtained for P.merguiensis ( from 58/5 to 65/5 %) and the least catch for P.indicus ( from 0/04to 1/1 % ), respectievly.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Harmful algal blooms resulting in red discoloration of coastal waters in the Persian Gulf, Iran were first observed in January 2007. The species responsible for the bloom, which was identified as Cochlodinium polykrikoides, coincided with massive aquatic organisms’ mortalities in the Persian Gulf. In order to provide optimum growth and bloom forming, C. polykrikoides cells were sampled during the bloom conditions in the coastal waters of Persian Gulf. After adaptation in filtered seawater, they isolated by positive phototropism characteristic of this species to light. They were grown in modified media culture at different salinity (30, 32 and 35ppt), temperature (20, 23, 26 and 28ºC) and intensity (35, 70 and 90 µmol m-2 s-1) with an initial cell density of 50 cell mL−1. The results of the present study clearly showed that the highest alga biomass was obtained following culture by using A2 medium under the 32ppt salinity, 26°C temperature, and under a 11h light:13h dark photoperiod regime at a light intensity of 90 µmol m-2 s-1 provided by cool white fluorescent tubes. Mean cell density of C. polykrikoides in a 60 liter tank for ten days reached to 32 × 106 cell L−1. Moreover, individual C. polykrikoides chain with 18 cells was observed for the first time in cultures. Based on the results from the present study, as mentioned above, providing suitable media culture and physical condition (light intensity and temperature), bloom forming of C. polykrikoides start from day 8 to 10 and will be continued until day 24 t0 28. In the other hand, C. polykrikoide cells immediately crashed and destroyed.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Annually, many data of hydrology and hydrobiology of the southern Caspian Sea at Iran's coasts were collected by Caspian Sea Research Institute of Ecology. The data which had been collected by researchers submitted annually in several reports but has not been processed all at once. Fluctuations of various parameters were surveyed and the relationships between them were analyzed. The main goal of this research is to analysis the data were obtained from 1994 to 2006 and show changes the concentration of various parameters in the Caspian Sea. Physicochemical data indicated that the average trend of transparency and salinity was decreased from 1994 to 2006 annually, where the salinity value was decreased from 12.37 ppt (part per thousand) to 11.5 ppt. The average of dissolved oxygen was increased from 6.4 to 8.6mg/l. pH has slightly fluctuated from 8.15 to 8.31. However, with increasing depth from surface to bottom, the average of dissolved oxygen was sharply decreased (DO concentration in surface and 800 m was 7.18 and 1.45 mg/l, respectively). The trend of salinity and pH fluctuation was very slow with depth but the salinity has an increasing with incrementing of depth but pH has a decreased trend. The average of organic and inorganic phosphorus and TP was nearly increased. The average of Nitrate and Silica sharply increased comparing to depth but the average of Nitrite and organic Nitrogen decreased. The results showed that the temperature fluctuation in different water layers was low in winter but the dramatic decreasing of temperature was occurred at 10-20 m (in spring), 20-50 m (in winter) and 50-100 m (in autumn). With increasing of depth (Slope of the Sea), transparency and salinity values have an increasing while DO and pH showed decreased. As a whole, 335 species of phytoplankton were identified, there are 70 species in advance as these species were not seen in this period but 96 of novel's species have been recorded. The lowest and the most of phytoplankton biomass was recorded in 2006 and 2001 while the biomass was 59 and 1034 mg/m3, respectively. Albet, the lowest biomass was recorded at the depth of 100 m (24.1 mg/m3) but the maximum was observed in surface layer (1344.1 mg/m3). The average of phytoplankton biomass was increased after arrival of the ctenophore. There was a significant difference between the average of biomass in different seasons before and after of the ctenophore invasion (P〈0.001). Bacillariophyta and Pyrrophyta have the most cell abundance with a total of biomass of 52.7 and 37, respectively. From 1994 to 2006, species diversity (Shanon-Niner), evenness and richness were estimated between 3.02-1.29, 0.28-0.61 and 4.32-7.60, respectively. A total of 65 zooplankton species were identified with a frequent species in the Caspian Sea before the ctenophore invasion, while the species diversity decreased after the invasion. The high and the lowest of species diversity was recorded in 1994-1995 and 2006 and in 1999 the biomass of the zooplankton were observed between 12.6 mg/l and 363.8 mg/l, respectively. After arrival of ctenophore, the averages of zooplankton biomass at of the different depths were sharply decreased and were less than the ctenophore invasion. The result showed that there was a significant difference among the average of zooplankton biomass in two periods, seasons and west, middle and east regions as follows: P〈0.001, P〈0.008 and P〈0.01. The maximum abundance and biomass of zooplankton belonged to copepoda with %51.5 and %63, respectively. Rotatoria falls in the second class from 1994 to 2006 (during 1994-2006), species diversity, evenness and richness were varied between 0.19-1.6, 0.08-0.52 and 0.37-2.29, respectively. The species diversity of macrobenthic organisms at the same period s followd by zooplankton changes which sharply decreased. The average of benthic biomass reduced from 13.7 g/m2 in 1994-1995 to 1.8 g/m2 in 2004 but sharply increased in 2005 with a maximum value of 46.7 g/m2. With increasing of depth, the average of benthic biomass was sharply decreased. There was a significant difference (P〈0.001) in macrobethic organisms abundance before and after the ctenophore invasion, but it did not show a significant difference between seasons and different regions (as follows: P〉0.137, P〉0.782). Before the presence of ctenophore, the worms had been constituted a dominate group with a approximately %45 of total abundance and also %20 of their biomass. After this period, their frequency was sharply increased (more than %85) but the maximum value pertains to Cardidae (more than %90). The species diversity, evenness and richness were varied between .69-2.51, 0.23-0.63 and .011-3.79, respectively. AMBI software, Shanon-Viner parameter was moderate in all seasons from 1994 to 1996 but this parameter was reduced in a bad limit (boundary) in the most seasons from 2002 to 2005. The main parameter of M-AMBI consists of several parameters and also approximately showed similar changes such as Shanon -viner parameter. On basis of this parameter, the ecological quality condition of Caspian Sea was superior limit in all seasons from 1994 to 1996 but after the following years were decreased from good to moderate limits (After the presence of ctenophore). Relationship between abiotic variants and phytoplankton indicated that there was a direct relationship between transparency and salinity while there was a powerful and reversal significant relationship between transparency water temperature, transparency in organic Nitrate, phytoplankton number and transparency phytoplankton biomass. The comparison between different variants average in two periods (before and after the ctenophore invasion) indicated that the average of Kilka catch was decreased, the relative frequency of clupeonella engrauliformis and clupenoella grimmi was sharply reduced but the relative frequency of Clupeonella cultriventris was sharply increased, the species diversity, evenness and richness and the number of zooplankton species were sharply decreased, the average of biomass and transparency was sharply reduced, the average of dissolved oxygen and liza saliens or liza auratus catch were increased. These difference were often significant (P〈0.05). Therefore, with the ctenophore invasion into the Caspian Sea, the primary production was increased, the biomass value of zooplankton and specially Kilka which fed on zooplankton were sharply decreased while the fish such as Rutilus frisi kutum and mullet (Liza salins or Liza aurratus) which fed on benthic were increased.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Region South East of the Caspian Sea (area Goharbaran) having valuable resources biological flora and fauna, the diversity of commercial fishes, especially reserves the exclusive sturgeon as well as reserves abiotic such as oil and gas resources and transit of goods through Bandar Amirabad to Central Asia , the ecological conditions for the implementation of the project is very necessary.The aim of this study was to determine species composition, spatial and temporal distribution of plankton and fish of this region.Plankton sampled from different depths (5, 10 and 15 m) were carried out.Sampling of phytoplankton did by Ruttner and sampling of zooplankton did by net with mesh size 100 microns.The fish were sampled monthly from December 2013 to July 2014 and within months was carried out. From livestock gill Monofilament.. In this study, a total of 130 species of phytoplankton of 7 filums Bacillariophyta (60 species), Pyrrophyta (23 species), Cyanophyta (22 species), Chlorophyta (14 species), Euglnophyta (9 species), Haptophyta (1 species) and Chrysophyta (1 species )and 24 species of zooplankton branch of Copepoda (5 species), Rotatoria (7 species), porotozoa (3 species), Cladocera (9 species), and Meroplankton (2 species) of larvae of Cypris Balanus and bivalves Lamellibranchiate larvae and 256 fish Acipenser persicus at 5, Alosa braschnikowi 71 number, Alosa caspia 40 number, Benthophilius lipidus 1 number, Cluponella cultriventris 72 number, Cyprinus carpio 1 number, Liza saliens 15 number, Neogobius bathybius 1 number, Neogobius caspia 5 pcs, Neogobius flauviatilis 19 number, Neogobius gorlab 6 number, Rutilus kutum 14 number, Rutilus rutilus 2 pcs, vimba vimba 4 number was observed.Different ecological conditions appointment dietary needs and relationships of organisms and their adaptations to the environment, the density and distribution of different species of phytoplankton, zooplankton and fish specifies.Also the Caspian Sea due to the type of biological species and number of endemic species (42%) in addition to comb jelly invasion, were force of the effects some species like Gloeotrichia Echinulata and as a result, now or in the future, more species will be observed and recognized will be of most interest. Also Psedonitzschia seriata ability to produce Domick acid that can be hazardous to aquatic animals and even human, was in Goharbaran area. This was considered for fishes of the southern Caspian Sea and ecological distribution of most species depends on the region. The abundance of two species of whitefish and pelagic fish in Ghahrebaran region is more than the whole Caspian Sea. On the other hand, the dominant phytoplankton of this region is Bacillariophyta and dominant zooplankton is Copepoda, which shows the goodness of these plankton branches, and by changing the various factors as the different terms of receiving solar energy and resulting in temperature and water currents can cause seasonal differences in the density of the Bacillariophyta branch and also the Copepoda, therefore one of the most important factors is season, and in the winter, when the aquatic rotation of this ecosystem increases, it increases the nutrients and moves it from the floor to the water column, and as a result, increasing the amount of silica in various levels of water can affect the nutrition of fish.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was carried out for growth of organisms survey on artificial reef from 2004-2006 after establishment in Hormozgan offshore waters (Bandar Lengeh area). Also during this study we were examined some biological factors including: phytoplankton, zooplankton, ichthyoplankton and benthos from spring 2006 to winter 2006. In this study 43 phytoplankton genus were identified, 28 Bacillariophyceae (Diatom) , 11 Dinophycea , 3 Cyanophycea and 1 Euglenaphycea. Bacillariophycea were dominant, Cyanophycea were high density observed in summer and Euglenaphycea was only observed in winter. The most abundant genus of diatoms were: Rhizosolenia , Navicula , Nitzschia , Coscinodiscus. Ceratium , Prorocentrum and Protoperidinium belong to Dinophycea , Oscillatoria belong to Cyanophycea were more than other genus. Copepoda and Nauplius were the most zooplankton and other group were respectively : Oikopleura, Polychaeta and Chaetognatha. The highest density of zooplankton was seen in winter. The statical study between different stations didn't show any significant (p〉0.05). 6 ichthyoplankton families were seen and identified. These families were Clupeidae, Gobbidae , Callionymidae , Sparidae, Engraulidae and Scianidae.The high density were respectively in summer and spring. The highest annual mean belong to Gobbidae family. Benthos groups were including: Crustacea, Mollusca , Polychaete , Nematoda , Nemertin , Foraminifera , Opiouridae and Echiura. Annual high density of Crustacea were observed in spring season, Polychaete and Mollusca were observed respectively in summer and winter. Organisms which growth on the artifical reef were consist of 12 group. These Organism were Barnacle belong to Crustacea with one genus (Megabalanus tintinnabulum), Sponga with 5 families and Tunicate. The highest density was in 2005. We were seen increasing in size in some organisms such as Crab, Polychaetes, Bivalvia and Fish Larvae. Statical study didn't show any significant between organisms in different parts of artificial reef (top, mid, bottom) and kind of artificial reef had no effect on growth of organisms but Barnacles had high density on mixed artificial reef.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The presnt study has been carried out to evaluate the Nannochloropsis oculata culture performance in 100L columnar plastic bags under two chemical media (TMRL and CONWAY) and 3 light regimes in the controlled conditions. Algae used for the experiment has been provided through culture of primitive stock and by transferring it to 2 L glassy erlenmeyer and 15 L plastic containers (as intermediate stage) using CONWAY media respectively. Daily evaluation of algae concentration was carried out during the 18 days culture period. At the end of the study produced algae has been sedimented to be used for evaluation of the dried matter and algae biomass. Results of the study showed that the concentration of the algae culture was 22±3.34×106 cells. ml-1, at 8th day, and reached the concentration of 26.58±4.02×106 cells. ml-1 at the final day of the culture course. Although the results revealed the possibility of achievement of acceptable concentration for the N.oculta by the method adopted in the present study, but the achievement was not such favourable to be considered as an altenative for the common method. Nevertheless it could be considered as an alternative for the constrained situations. Moreover according to the results there was no significant algae concentration difference between light regimes (P〉0.05). Similar results were observed for the interaction effect of chemical media and light regimes. Meanwhile the ratio of dried matter obtained from algae under the TMRL media was significantly (P〈0.05) higher than that obtained from CONWAY media, but reversed results were observed for algae biomass. Light regimes were not significantly (P〉0.05) affect the algae production. Finally it could be concluded that the N.oculata algae could be successfully cultured in plastic columnar bags under the controlled conditions but the method adopted in the present study could be applicable in the improper conditions.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Cheetgar lake or Persian Gulf Martyrs' lake is an artificial lake in the North west of tehran is located in district 22 of tehran municipality.The lake covers an area of 130 hectares, which is located north of forest park Cheetgar. In south,to Tehran-Karaj highway, In north Hemmat expressway, from East to Azadegan expressway and west and from residential areas district 22 of tehran municipality is limited. Kan River from East and Vardavard of West cheetgar Lake crossing and kann river is the main source of water of the Cheetgar lake now. Plankton is one of the important factors related to water quality. In this context, understanding the biological and nonbiological lake and its ecological status of a useful tool for managing sustainable exploitation with an emphasis on water quality is maintained. This study focused on zooplankton structure, biodiversity, relationship between a biotic parameters and zooplankton variation, and trophy state of the Persian Gulf Martyrs Lake (Chitgar-Tehran). Based on the lake condition, samples were collected by Juday net from the bottom to the surface (of a cylindrical column) at the 5 stations between 2013 and 2014. Than 4% formalin fixed samples and transferred to the laboratory for quantitative and qualitative study. In laboratory planktonic samples after determining the volume and mixture, were transferred by pipette to 5ml chambers and after sufficient time to sediment, were identified and counted by inverted microscope.This study identified 36 zooplankton taxa comprised of Arthropoda (6 genus), Protozoa (6 genus), Rotatoria (20 genus), Nematoda (1 genus), Gastrotricha (2 genus) and Oligochaeta (1 genus). The Rotatoria abundance average was measured 61 ±18 ind.l-1 in the lake. The Nematoda, Gastrotricha and Oligochaeta taxa were measured the lowest abundance (〈1ind.l-1) in this study. The annual average zooplankton abundance was measured as 72±18 ind.l-1. The PCA displayed, the Rotatoria Trichocerca sp. and Polyarthera sp. were dominated with high components loading, low variance and highabundance. The CCA showed, there was no correlation between Rotatoria abundance and a biotic parameters. Based on the zooplankton structure and bio-indicator, the lake situation is in the meso-oligotrophic category. Thus, it is might be increased eutrophication trend due tono management and no aquatic control in this ecosystem.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Mullet and other bony fishes are caught by beach seine in Iranian waters in Golestan, Mazandaran and Guilan provinces. In this investigation which had conducted in commercial regions during 2003-2004, we estimated catch and CPUE, species composition, length, weight, age of two species of mullet and Salmo trutta caspius; von Bertalanffy growth parameters, mortality, biomass and MSY of Liza aurata. The total recorded catch of mullet was 3870 mt and L. auratapre dominated (98.5% of total catch of mullet). CPUE of two species of mullet; L. aurata and L. salienswere 69.6 and 1.1 mt purse seine, respectively. The catch of Salmo trutta caspius was negligible (about 3.6 mt). Biomass and MSY (maximum sustainable yield) of L. aurata were estimated to be 11019.8 and 3322.6 mt, respectively.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The anthropogenic affectation was evaluated on the coast N of the Gulf of Batabanó in May 2003 (corresponding to the provinces of Matanzas and Havana), in areas located in the line of the coast. The results were compared with the historical information of the sector. In the coast N and the Ensenada of the Broa, the parameters oxygen saturation, DBO5 and DQO showed characteristic high values of eutrofication. The biggest contribution in the Cianoficies was in the near coastal areas to sources of organic contamination. In the case of the nutrients they show specific data of mesothrofic waters with tendency to the eutrofization and the silts presented a high affectation for toxic metals. The area near to Guanímar is distinguished to present conditions of organic contamination that favor heterothrofic conditions, corroborated by a prevalence of the processes of mineralization of the organic matter over primary production and lows values of fitoplankton concentration. On the contrary, in the region of Surgidero of Batabanó, the processes of synthesis of organic matter prevail suggested by a high primary production, and concentration of fitoplankton, with low breathing levels and mineralization of the organic matter, that indicates that the system is behaving autothrofically. In a general way, this sector is very affected by the anthropogenic impact. The information obtained is of great importance for the development of the fishing and tourist industries in the area.

Description: Published