ALBERT

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: 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: 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: 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

Description: Published

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

Description: Published

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

Description: Published

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

Description: Published

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: 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: 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: 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: 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: 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: 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: 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 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: 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

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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

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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

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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

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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

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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

Description: Published

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

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 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

Description: Published

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: 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: 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: 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

Description: Oman sea is an important aquatic part of south-east part of iran that lies from 27°N(Hormoz strait) until 25° 45′N (Gwatar Gulf) that is next to two Southern Province ,Hormozgan ann Sistan-o- baloochestan. Sampling was carried out from march 2007 and 2008 to September 2007 and 2008 in two period of time postmonsoon and premonsoon . A total 24 station on 10 transect 4 stations were on each transect 1 and 2 with 10 miles far from each other and for the others 2 stations were on each transect. A 0.1 m2 VAN – VEEN GRAB was used for sediment sampling and a CTD was used to record physical data of water column. Macrobenthos frequency data and biodiversity indices were used to determine of density and biodiversity of macrobenthos respectively. Wet weight was used to determine wet biomass of macronenthos. Among benthic invertebrate polychaete with average 800 ind-2 and then amphipods and gastropods were the most abundance . Yearly density of macrobenthos showed polychaete with the average of 500 ind.-2 in 2007 and 1000 ind.-2 in 2009 was the most abundance . Macrobenthos density in postmonsoon was more than premonsoon.p〈0.05. An increasing and decreasing in density and biodiversity was obtain from coast to depth respectively p〈0.05. There was no significant different between macrobenthos density from Hormoz strait to Golf of Guiter.p〉0.05. There was a negative regression between macrobentos density and depth(p〈0.05) and positive rsgresion between macrobenthos and oxygen concentration and temperature.(p〈0.05). There was also a significant relationship between macrobenthos ,coppepda and polychaete density with organic carbon.p〈0.05. Bimass changed from strait to Golf and coast to depth increasingly.p〈0.05.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was conducted to study of Hydrology, Hydrobiology and Environmental pollution in the southern of the Caspian Sea. 33 stations were selected from Astara (in the west) to Hassan gholi (in the east). In each station, sampling carried out at suface, 10, 20, 50 and 100m depths. Sampling was performed during four seasons in 2004. Sampling stations also divided into three regions, including west (from Astara to Ramsar), middle (from Ramsar to Sari) and east (from Amirabad to Hassengholi). The results showed that maximum of water temperature was 24 ?C at summer in the eastern region while the minimum of water temperature in winter season has been 9.7 ?c in the western region. The average of dissolved oxygen concontration in spring , summer, autumn and winter season were 6.9 , 6.6, 8.2 and 6.7 mg/l , respectively. The maximum value of salinity was observed in spring (13.55 ppt) and minmum value in winter (8.24 ppt). The average of total nitrogen concentration were season was 711, 884, 583 and 669 µg/l in spring, summer, autumn and winter repectively. The average of total phosphorus concentration was 27.9, 37.1 and 42.6 µg/l in spring, summer, autumn and winter, respectively. The average of dissolved silica concentration has varied from 167 to 923.6 µg/l. The five phyla of phytoplankton have identified. The most species diversity was observed in winter (70 species) but the low species diversity has obtained in autumn. The most phytoplankton population was in spring and summer seasons. The cell abundance of phytoplankton in different seasons was fluctuated from 3914*103 to 17337*103 ind/m3. In addition, the phytoplankton biomas was varied 11.4 to 30.7 mg/l. Result showed that distribution of phytoplankton are varied at different areas, layer, seasons and stations. The average of cell abundance of zooplanktons was varied from 2023 to 12364 and/m3 at different seasons. The mean of bioman varied from 9.40 to 43.48 mg/l. In this study, 17 species and one class of macrobenthos were identified. The frequency of Annelida and Biovalvia was higher than all macrobenthos. The average of macrobenthos was 1218±851 ind/m2 and their biomass was 14±15 g/l. The average of PAHs concentration were 0.038, 0.028 and 0.21 mg/l in spring , summer and winter, respectively. The decending trend of heavy metal concentration were Fe〉Mn〉Zn〉Cr〉Pb〉Co〉Cd〉Cu at different seasons in 2004. The maximum concentrations of organochlorine pesticides (OCPs) components in three regions of sampling zone such as , -BHC (middle), β,-BHC (middle), DDT (east) and dieldrin (east part) were 88.3, 35.0, 74.3 & 79.1 g/l during spring, summer, fall and winter, respectively.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In the early 1980s, an alien ctenophore Mnemiopsis leidyi already known as a gelatinous zooplankton was transported (likely via ballast waters) to the Caspian Sea from its introduced or native water of the Black Sea or western Atlantic which caused negative impacts. In this report, distribution of M. Leidyi, planktonic and benthic organisms had been investigated in the Southern Caspian Sea (Iranian waters) in 6 transects consisted of Lisar, Anzali, Sefidroud, Nowshar, Babolsar and Amirabad at 26 stations during 2005 and 2006. As a whole, 1422 samples had been analyzed included 258, 346, 217, 117 and 484 belong to ctenophore, phytoplankton, zooplankton, benthos and physicochemical parameters, respectively. M. leidyi abundance and biomass were fluctuated between 284-2751 ind.m-2 and 16.9- 390/9 g.m-2 respectively in 2005 while maximum abundance and biomass were recorded in autumn and minimum in winter. In 2006, its mean abundance and biomass were 184-2150 ind.m-2 and 9.1- 209/8 g.m-2 respectively. M. leidyi maximum abundance and biomass were noted in summer and its minimum in spring and winter months. Overall, mean M. leidyi abundance and biomass were recorded in 20 m within 1202 ind.m-2 and 139.5 g.m-2 respectively. Maximum size of the ctenophore was recorded as 55 and 60 mm in 2005 to 2006 respectively, while less than 10 mm length frequency consisted 83.16 and 82.88 per cent of total population. Spatial_ temporal distribution of M. leidyi in different regions showed it was more abundant in west and east (714- 4494 ind.m-2) ratio to central parts (13-1519 ind.m-2) of the Southern Caspian Sea. Species composition of zooplankton had shown the negatively impacts of M. leidyi invasion in the period of sampling as the only 17 holozooplankton were determined with Rotatoria (7 species), Copepoda (4 species), Ciliophora (4 species) and cladocera (1 species). Zooplankton maximum abundance and biomass were recorded in February (3039742901 ind.m-3 and 372.1575.4 mg.m-3) respectively and its minimum were in July (12211601 ind.m-3 and 6.9 7.7 mg.m-3) respectively which was belonged to Rotatoria (76%) and Copepoda (10%). In this study, 21 species of benthic fauna were deter minted belong to Pseudocumidae (5 species), Gamaridae (4 species) Amphartidae (3 species), Oligochaeta, Balanidae, Xantidae, Nereidae, Scarbicularidae, Carididae, Mytilidae, Herpobdellidae and Chironomidae (each 1 species). Oligocheata was recorded with maximum abundance (943 2502 ind.m-2) and Bivalve consisted of higher biomass (68.7162.5 g.m-2). From five phyla of phytoplankton, 172 species were determined of Chrysophyta (74 species), Cyanophyta (32 species), Chlorophyta (32 species), Pyrrophyta (24 species) and Euglenophyta (13 species), in which Chrysophyta and Pyrrophyta were noted as main groups with their maximum abundance (up to 65%) and biomass (93%). Maximum water temperature was recorded in August with 29.52.5 ֯C and minimum in February by 9.31.3 ֯C. Mean value of salinity was 12.010.90 ppt, secchi disk ranged between 0.2 to 7 m and oxygen demand varied from 5.95 to 10.54 mg. l-1). Moreover, silicate concentration was recorded between 200 to 300μg.L-1, Phosphate measured from 31-47 μg.L-1, Ammonia varied in 10-29 μg.L-1, Nitrite (0.6- 1.7 μg.L-1), Nitrate (0.06-4.20 μg.L-1, which mainly accumulated in coastal waters of the southern Caspian Sea.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was performed to investigating of distribution, biomass estimation and preparing Atlas of seaweeds in coastal and Islands of Persian Gulf (Hormozgan province). The samples were collected monthly from Sep. 2001 to Aug. 2002 in 6 stations of coastal and from Nov. 2002 to Oct. 2003 in 4 stations of Island of Persian Gulf in periods of low tides. For assessment of biodiversity and biomass estimation, the samples were taken from quadrate with 0.25 m2 (0.5m x 0.5m) area in random fashion. During this study 78 species of 4 divisions of seaweeds were identified. Rhodophyta represented 38 species, Chlorophyta 21 species followed by 18 species of Phaeophyta and only 1 species of Cyanophyta. The maximum and minimum species diversity of seaweeds was 74 and 31 species and related to Lark Island (St8) and Michail (St.5) respectively. Although some species such as Gracilaria corticala, Gelidiella acerosa, Laurencia snyderia, Colpomenia sinousa, Padina australis and Dictyosphaeria covernosa were abundant-in-all-stations-during-period-of-this-studynbut-some-species-were-not-see in some stations, such as Turbinaria conoiedes only in Lark island (St.8), Spatoglassum variable and Sleochospermum marginatum in Lark (St.8) and Qeshem islands (Sty), Codium papilatum and Ulva spp. in Lark and Hormoz (St. 7) islands, and Sargassum ilicifolium in Bandar Lengeh (St.2), Shiyo (St.6), Larak (St.8) and Qeshem islands (St. 10). The maximum and minimum value of algal biomass (wet weight) was recorded in Bandar Leneeh (St.2) with 1058 qr.m-2 and Oeshem islands (St.9) with 391 gr.nf2 and there was significant difference between two stations (P〈O.05). Also, the maximum algal biomass was recorded in summer (1466 gr.m- ) and in Tahoneh-Gorzeh (St.4) and minimum value (130 grem-2 ) in Qeshem islands (St.9). In the other hand, the maximum value of algal biomass was recorded in Brown algae division (824 gr.m2) and in Bandar Lengeh (St.2) and the minimum value of algal biomass were recorded in Green algae division (26gr.m-2) and in Hormoz (St. 7) and Qeshem islands (St.9). The average biomass of red algae, brown algae and green algae was 559 gr.m-2 (St.4), 1160 gr.m-2 (St.2) and 519 gr.Bf2 (St.4) respectively. The maximum and minimum length of two brown algae Sargassum sp. and Padina sp. were recorded in spring (growth season) and summer respectively. Also the maximum and minimum dry on wet weight percent were recorded in summer and spring and therefor, there is significant difference between different seasons (P〈O.05).

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 t 0 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: Published

Description: In order to sample, identify and determine Seaweed biomass in the Oman Sea coast (Sistan & Baluchestan Province) with 300 Km length from Gwatr area (with 25 10 N & 61 30 E) to Mydani (25 24 N & 59 5 E) during two years (from Octobr 2001 to September 2003), eleven regions of Gwatr, Passabandar, Beris, kachoo, Ramin, Chabahar, Pozm, Gurdim, Tang, Jood and Mydani were selected as sampeling stations from east to west. Seaweed growth area in intertidial zones determind by measuring and recording of geographic positions by metertape and GPS, then with the help GIS system and satellite maps, area, situation and maps of survey areas, were obtained 15 transects were determind with equal distance in coast area and monthly sampling were done randomly by quadrate 50*50 Cm the samples were transfered to the lab and the weight of each species was obtained after being cleaned, and separating. The biomass of each species per area unit and in the total area was obtained after determing the average weight of species. Also the prefered zones of each species were determined through the maximum number of presence in the transects. Along with this research, the Seaweed species were reconized according to the present references. The photographs were taken and the herbarium sheet was obtained. The samples were sent to experts for final approval. To compare the biomass changes during two years (2002 & 2003), this research was with the same methods of first year from October 2002 to September 2003 in Gwatr, Beris, Ramin, Tang and Jood. During this research 180 species were collected. Among these seaweeds, 160 species (composed of 39 species green algea, 39 species brown algae and 82 species red algae) were identified. There were some important families including green algae (Ulvaceae & Caulerpaceae), brown algae (Sargassaceae & Dictyotaceae) and red algae (Gracilariaceae, Gelidiaceae and Hypneaceae ). Wet biomass of Seaweeds in the total area of Sistan & Baluchestan coasts were 10269399 kg in 2002. Among this biomas, 2645223 kg (%25.7) green algae, 2953279 kg (%28.8) brown algae and 4670897 kg (%45.5) red algae were estimated and the monthly average for then were obtained 264522.3 kg, 295327.9 kg and 467089.7 Kg respectively. The maximum biomass was obtained 922246 kg in Chabahar and minimum biomass was obtained 1418 kg in pozm. The amount of alginophyte (Sargassum Spp.), agarophyte (Gracilaria, Gelidium & Gelidiella) and karaginophyte (Hypnea musciformis) were 159777 kg, 806915 kg and 188783 kg respectively. In second year (2003), the biomass of wet weight was 4114655 kg in 5 zones. Among this biomass, 849227.5 kg (%20.6) green algae, 1669792 kg (%40.6) brown algae and 1595636 kg (%38/8) red algae were obtained. The monthly average were 70769 kg, 139149.3 kg and 132969.7 kg respectively. The biomass of alginophyte, agarophyte and karaginophyte were 163776.4 kg, 481642.6 kg and 64310.1 kg respectively this year.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: From December 1998 to March 2001, (28 month) a survey in Iran waters were completed. Each month, 50 stations in four depth stratums that is, below 10 m, 10-20 m, 20-30 m and above 30 meters from Bahrekan to dayyer were trawled. Some Biological parameters such as sex stages, sex ratio, total length, species composition and some environmental factors such as water temperature, air temperature, salinity, soluble oxygen, acidity of seawater were measured. In this survey, the effects of environmental factors on shrimp behavior and landings were assessed. According to analysis, spawning season extends from January to May. Maximum percentages of mature stage (4th stage of maturity) were observed to be 53.4% in April 1999 and 47.6% in May 2000. Water temperature and salinity were 23.1 centigrade and 37.2 PPT and 21~'C and 38.7 PPT in spawning seasons of 1999 and 2000 respectively. The catch composition of shrimp in fishing season (July to September) for the years 1999 and 2000 has been observed to be 60.2% and 66.4% for 〈i〉Penaeus semisulcatus〈/i〉, 37.1% and 30.4% for 〈i〉Metapenaeus affinis〈/i〉, and 2.5% and 2.8% for parapenaeopsis stylifera respectively. Maximum catch per unit effort (CPUE) in fishing season of 1999 and 2000 were observed to be in depth ranges of lower than 10 meters and 10-20 meters respectively. Analysis of length frequency data shows that the first schools of juvenile tiger shrimps appear in middle region of Persian Gulf from May to June (in low density). In later months (July to August), the schools of juvenile shrimps gradually appear in northern areas. After closure of shrimp fishery (late September) the density of adult shrimps in northern area increase. These shrimps have an average length of more than 15 Cm and are sexually matured. Analysis of sex ratio shows that in fishing season, the number of Male and females are almost equal (sex ratio=1). In Nov. and Sep., the number of females increases (decrease of sex ratio). In spawning season the number of females decrease (increase in sex ratio) but approaching to the coming fishing season the sex ratio tends to become 1 due to recruitment. Observations show that during fishing season the sperm sacs of Male gradually evolve so that at the end of fishing season, the sperm sacs are seen as two white tissue under the last pairs of Pereopods. In other observations, some of sperm had come out from steam of pereopods and cleave to legs of shrimp (both males and females). These observations show that shrimp schools come to fishing grounds for copulation. The stock-recruitment relation has not been proved to be correct and environmental factors has had more effect on size of shrimp stock. A linear relationship with a high correlation coefficient of r〈super〉2〈/super〉=0.9 between prefishing season CPUE and the landings of the same year was established. (Landing =56 CPUE+286). Finally, it is shown that, lower water temperature in spawning season results in better spawning and thus higher yield

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Catlassfishes are one of valuable stocks in the Oman Sea and Persian Gulf that need enough knowledge of biological and environmental characteristics of provinces. Thus this project was performed. In this study, the stock condition of Catlassfishes was considered from March 2000 to September 2001 in the Sirik and Hengarn area. Sampling carried out seasonally with bottom trawl. Dominant species was Trichiurus lepturus. Anal length compared in the both Sirik and Hengam areas. The results showed a significant difference (P〈0.05) between areas. Biomass and maximum CPUA were respectively estimated as 2856 tons and 3198 Kg/nm2 for Sirik area and 31 78 tons and 5204 kg/nm2 for Hengam area. IÄ and K were obtained i 15cm and 0.93, respectively. The instantaneous natural mortality co-efficient (M), Total mortality coefficient (Z) and exploitation ratio (E) was estimated as 3.65, It 15 and 0.65, respectively. Anal length per weight relationship obtained as 1 497X2*2849 2.2964 in Sirik and y=o.14649x in Hengam. This species seems to spawn throughout the year but two spawning peaks were determined in spring and Autumn. I-M50 was 27.5 cm. Female to male sex ratio was estimated 1.59 and showed a significant difference sexes. Minimum and maximum Fecundity were 2835 and 186000, respectively. Main food item was obtained sardine MSY values were estimated as 1642 and 1827 Ton for Sirik and Hengam respectively. Therefore, it is suggested that fishing should be done with care out of fishing season.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Nowadays, the use of live food enrichment is very common in aquaculture and as a practical method introduced. Artemia a potential food source and quality is suitable, it will have used for feeding fish and crustaceans (shrimp). In this study, Artemia enriched with unsaturated fatty acids used for increase the sexual maturity of the white leg shrimp (Litopenaeus vannamei). Thus, the young brood stocks transferred to Bandarga Research station. In order to achieve optimal weight, Brood stocks were feeding by food concentrate and food frozen fresh. In this study such as 3 treatments each with 3 replicates, which brood stocks were stocking in the fiberglass thank with density 2 to 3 (pieces/m2). They were feeding with meals different including 1) squid , pen shale and marine polychaeta worm (Perinereis nuntia), 2) squid , pen shale and Artemia biomass "fransiscan", 3) squid , pen shale and Artemia biomass enriched with unsaturated fatty acid (HUFA) SPARI SELCO solution after were eye ablation. The results showed that sexual maturity increased in the brood stocks fed with Artemia enriched which with significantly higher brood stocks fed with Artemia biomass and the marine worm (P 〈0.05) whereas significant difference was not found in the rate of sexual maturity brood stocks fed with Artemia biomass and marine worm (P〉 0.05). The other hand, histological studies showed that brood stocks fed with Artemia enriched than other two treatments contain were many mature follicles ready for ovulation. However, there was more absolute fecundity in the brood stocks fed with Artemia enriched, but don't found any significant differences in competition with other two treatments (P 〉 0.05). In addition, during this period, measured and recorded all factors physicochemical water and environment daily. Following this study showed that if the Artemia enriched as part of the diet can both caused eliminate unsaturated fatty acid deficiency diet and improved ovarian development and increase sexual maturity brood stocks female in a short interval. Finally, the results analyzed with statistical software spss 9.0, one way ANOVA and Tukey test.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was conducted to determine of phytoplankton abundance and diversity of water and their spatial and temporal fluctuations in the Mazandaran coastal of Caspian Sea in 6 months, at 4 transects (Tonekabon, Nowshahr, Babolsar, Amirabad) during different season of 2012-2013. 72 samples were collected at surface layer of water in 5, 15 and 30m depths. The sampls were analyzed based on the standard methods. 112 species contributed in phytoplankton community structure which where classified in 9 phyla namly: Bacillariophyta (42 species), Pyrrophyta (18 species), Cyanophyta (14 species), Chlorophyta (15 species), Euglenophyta (11 species), Cryptophyta (2 species), Chrysophyta (3 species), Haptophyta (1 species) and Xantophyta (1 species). Meanwhile small flagellate algae with Maximum Linear Dimension (MLD) 〈10 µ observed which they classified in small flagellates. Mean annual phytoplankton abundance with standard error obtained 164 ± 32 million Cells/m3. Seasonal study showed that phytoplankon abndance of summer was 1.5 folds of spring. The value in auttuman was same as spring, however it increased sharply in winter. The mean phytoplankton abundance of winter was 5 folds of the other seasons. Mean phytoplankton abundance of Tonkabon and Nowshahr (west transects) were 1.6 and 2 folds of Amirabad (east transect), respectively. Bacillariophyta with 89 percent of total abundance was the predominant phylum and Pyrrophyta was the second one. The third and fourth of dominant phyla were Cyanophyta and Chlorophyta, respectively. Chrysophyta and small flagellates showed equal percentage of abundance (1.4 percent of total abundance). Monthly study showed that Chaetoceros throndsenii was the first dominant species in Ordibehesht, Tir and Shahrivar. However, the first dominant species in Aban, Day and Esfand were Thalassionema nitzschioides, Skeletonema costatum and Pseudonitzschia seratia respectively. Mean phytoplankton biomass calculated 156.5 ± 18.1 during the study period. The mean of biomass was higher in summer and winter than the two other seasons. Phytoplankton biomass was formed mainly by Bacillariophyta and Pyrrophyta in all seasons. The highest biomass were belonged to Cyclotella meneghiniana and Coscinodiscus jonesianus (Bacillariophyta) in spring and summer respectively.While in fall and winter Prorocentrum proximum was in the first place of dominat species. Small size and flagellates species of different phyla (Chrysophyta, Bacillariophyt...) had importance role for determination of ecological and water quality conditions during spring to autuman. The increasing of phytoplankton abundance within these times indicates to regeneration of nutrients or entrainment of nutrient-rich deep water. Dominant species were observed in single forms, small filament and loose colonies during spring to autuman. However, these form shifted to fair-long chains form in winter which it indicates to nutrient-rich water was brought to the surface by vertical mixing process. It seems that environmental stress and instability of ecosystem was benefit to Chaetoceros throndsenii and Pseudonitzschia seriata which are known as species with bloom potential. Ability of reproduction in sewage environment (Chaetoceros throndsenii) and toxin production (Pseudonitzschia seriata) are the ecological and physiological significant characters of the two species.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: For gathering of data on biometry and catch statistics, 5 mobile working group in the regions of Anzali, Kiashahr , Noshahr , Babolsar and Torkmen were involved from the start ( 2004/10/23 ) to the end of fishing season (2005/04/10 ). Gathered data were entered to the computer based on species. For data analysis different methods were undertaken such as Bertallanfy equation for growth parameter Beverton and Holt for total mortality rates, pauly's imperical model for natural mortality rate and cohort Analysis for biomass estimation. Total catch with taking into account of poaching, was estimated 15140 tons reported by scientific committee of catch and fishing harbor relief of Iranian Fishery Company. The total recorded catch of beach seine cooperatives was 10644 tons that comprise 70.2% of the total catch. Total catch of Caspian Kutum was estimated 6612 tons that had 1856 tons (22%) decrease with comparison of the last year. Biomass of Caspian kutum in Iranian coastal Water of the Caspian Sea in 2003-2004 estimated about 20400 tons. The total catch of golden gray mullet was estimated 4425.6 tons that constitute 29.2% of total catch of bony fishes. Biomass of this species was estimated 12200 tons and based on this amount of biomass, Maximum Sustainable Yield (MSY) was calculated as 3577 tons. Long nose mullet comprised only 1.4% of the mullet catch. The catch of common carp in 2004-2005 fishing season continued its increasing trend and caught in amount of 3087 tons by beach seine cooperatives that had 2.2 fold increase in comparison of previous fishing season. Most of the catch occurred in Golestan province and was immature and undersize and the length frequency modes showed moving towards bigger size and older age groups in comparison of previous fishing season. The catch of pick perch in 2003-2004 decreased with comparison of the last year and estimated about 22.5 tons. Most of the catch of pick perch was immature and undersize. Approximately all of the catch is due to releasing of fingerling of this species by Fishery Company especially in Guilan province. Total catch of bream was estimated 27.4 tons and most of which was immature and undersize. Population of asp is critically endangered and the catch of this species is very low (500 kg). Restocking of this species must be considered by Iranian fishing company.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In order to investigation effect of protein level on growth and carcass characteristics of rainbow trout, the experiment was carried out in complete ransoming design. The treatments were 1, 2, 3 and 4 which contained of 40, 45, 35 protein percent and commercial diet contained 40 % protein respectively. Four repeat were maked in each treatment. This experiment were conducted on 4000 juveniles rainbow trout with initial average weight of 24-26 gr, for 180 days after antiseptic processes in 16 little pound of 1.5x 6m on fish farming of Morvarid-E-Dimeh in Chaharmahal and Bakhtiari Province. The diets were formulated with local material which can providing nutritive requirement of fish in different stages of growth. The feed were given 3 times a day on biomass basis of little pound. In the during of experiment, once every two weeks, after anaesthetize 10 percent of fishes in each little pound were measuring about weight and length and the data were taken. At the final of experiment for determination of crud protein, fat, ash and dry matter, fish carcass were analyzed by AOAC procedure after removal of fins, fill gut and head. The results showed which feed conversion ratio affected by protein levels, and the best was in treat 2, which have been significant differences with others. Also weight and length fishes were affected by the rations and the differences were significant, as the largest length and weight were due to treat 2 and the least were in treat 3, which there were not significant differences between treat 1 and 4. Although, the diet protein level had effect on carcass chemical composition, but the differences were not significant.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: This study was conducted to determine the opening and closure of Penaeus semisulcatus fishing season in July, August and September during 2012 - 2014 in the waters of the Bushehr province . 30 stations were hauled based on a Stratified Random Sampling design in three depth layer of less than 10, 10-20 and more than 20 meters. The optimum dates of opening shrimp fishing season for the years of 2012-2014, were calculated as 4th, 28th and 13th July respectively. The closures of Shrimp fishing season for years of 2012-2014 were determined to be 10th September, 29th of August and 5th of September. The estimated biomass were for all of shrimp species in the years 2012-2014, 930, 1009 and 526 tonnes respectively. Penaeus semisulcatus contributed 92, 96 and 99% of the shrimp stock in the mentioned years.The CPUE (catch per hour) were calculated to be 1.6, 16.9 and 6.9 kg per hour, in the years 2012-2014, respectively. The highest aggregation of Green tiger Shrimp (P. semisulcatus) were observed in 10-20 depth meters layer in southern waters of Bushehr province at the fishing areas (Motaf to rostami). The changes in climatic conditions resulted in differen dates of the opening season and probable illegal fishing may have caused the reduction of shrimp biomass in recent years. Hence to Protect the stocks the economic species and the sustainability of shrimp fishing, it is neccesary to properly manage fisheries and determine the opening and closure fishing season Penaeus semisulcatus through conducting research surveys.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Estimation of Artemia resources on Uromieh Lake during (years2002-2003) showed huge reduction of Artemia cysts and biomass stocks than the previous years. Reduction of average annual precipitation in west Azerbaijan province during last 6 years than previous years from 32centimeter to 21centimeter has reduced the annual entered waters from the lakes basin rivers into the lake from(3.5-4.0)billion cubic meters to(1.8)billion cubic meters. During this period the entered fresh water in to the lake has been reduced, however the evaporation rate from 5750 square kilometer of Lake Surface has been continued at 3to4billion cubic meters per year. In spite of the fact that there are more than 5 billion tons salts on Uromieh Lake and that about 2 billion cubic meters of lake water is decreased annually due to negative balance between entered water and evaporation rate from Lake Surface, the water salinity on the lake has increased From 220 g/l in 1999 up to high saturated level atthe present. Increasing salinity on lake water up to high saturated level has caused to salt precipitate on lakes bottom and the Ionic exchange between lake water and beds natural precipitates that necessary to provide needed ions to photosynthesis was interrupted, so that the quality and quantity of primary productions on the lake has decreased and the lake has change to oligotrophic condition and in some seasons the turbidity of the lake has increased up to 5 meters. Above mentioned integrated factors have reduced Artemia stocks on lake during a few last years and this has resulted in stopping the cysts and biomass harvesting.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In order to studing and determination of Seaweed biomass in the Oman Sea coast (Sistan & Baluchestan Province), according to obtained reasults and experiments and observations on seaweed studies in 15 years ego, Beris, Chabahar, Pozm and Tang were high density zones and Jood and Lipar were low density zones in west and east of chabahar respectively that were selected for study stations. Total length of sistan and balochistan coasts from Gwatr area with geografical position 25˚ 10′ N & 61˚ 30′ E to Mydani with geografical position 25˚ 24′ N & 59˚ 5′ E were 354.3 Km. Among this length, 54.6 Km were rocky coast and 299.7 Km were sandy coast. Among this, 18.2 Km were high density zone and 281.5 Km were low density zone. Washout Seaweeds area in intertidial zones determind by measuring and recording of geographic positions by meter and GPS, then were obtained 2 transects determind with equal distance in high density area and 1 transects in low density for monthly sampling. The length of these transects were 100 meter and cross of Each transects were seaweed washed out average. The transects divided to 10 bluck and sampling were done randomly monthly from 5 bluck or 50 persent. The samples were transfered to the lab and the weight of each species was obtained after being cleaned, and separating. The biomass of each species per area unit and in the total area was obtained after determing the average weight of species and also determind geografical position by GPS. In relation to this project were done water sampling for recording of fisical chemistry factors. Total data for analysis recorded in this computer. During this research 9 species were collected. Among these seaweeds, 2 species green algea (composed of 2 families and 2 orders), 6 species brown algae (composed of 3 families and 3 orders) and 1 species red algae were identified. Wet biomass of Sargassum in the total area of Sistan & Baluchestan coasts were 445.9 ton in 2012. Among this biomas, 269.1 ton (%60.35) high density area (Beris 112 ton or %25.11, Pozm 83.7 ton or %18.76, Chabahar 59 ton or %13.22 and Tang 14.5 ton or %3.26) and low density zone 176.8 ton (%39.65). Monthly average were estimated about 74.3 ton (high density zone 44.9 and low density zone 29.5 ton). The maximum biomass was obtained 270.4 ton (high density zone 155.5 and low density zone 114.9 ton) in Azar and minimum biomass was obtained 3.5 ton in Esfand. At last, were suggested, This project were done in persian gulf coasts nessesery.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: In this study, the combination of length, growth rate, mortality rate and also the current of status Operation Carp and roach commercially as important species in southern waters were reviewed. Samples were taken from beach sine net catch and fish were offered at fish market. The age composition of carp and roach was 1 to 16 and 1 to 4 years respectively, most catch carp and roach was in length range of 31 to 39 cm and 18 to 20 cm respectively. Growth parameters during the program by ELFFAN I FiSAT for Carp and Roach obtained from von Bertalanffy growth function were L∞ =70.78 and 32.39 cm, K = 1.24/year and 1.24/year; respectively. the growth parameters such as infinite length( L∞), growth coefficient (K) and t0 age zero base on One Brtalnfy equation estimated, 78/70, 0/14, 32/39, 0/5 ,-0 / 5 Total mortality coefficient Using the method of catch curve (Z), natural mortality rate using the empirical formula Pauli( M) , fishing mortality (F) using the formula F = Z - M and Growth performance index (Ǿ) for Carp and Roach were obtained 1.5year-1,0.9year-1,0.5year-1,0.26year-1,1.24,0.4,2.85 and 2.54 respectively. The biomass (B) and Maximum Sustainable Yield (MSY) with the present effort for Carp and Roach were estimated 1628.7t, 368.9t and88.06t, and 32.7t respectively.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The Study of phytoplankton in the Caspian Sea was substantially started in the 1990s with the aim to produce and record data. phytoplankton study in this area became more important because of the occurance of some ecological events in recent years (such as bloom and arrival invader species). The study was seasonally conducted in western (Giulan province) to eastern coast (Golestan province) at 8 transects (Astra, Anzali, Sefidrud, Tonekabon, Nowshahr, Babolsar, Amirabad and Bandar Turkman) from inshore (5 m depth) to offshore (100 m). 476 samples were collected to study quantification and qualification of phytoplankton in 2009-2010. Results showed that 195 species of phytoplankton were identified in 8 phylums which were classified to Bacillariophyta (81 species), Pyrrophyta (33 species), Cyanophyta (28 species), Chlorophyta (38 species), Euglenophyt (11 species), Xantophyta (1 species), Chrysophyta (2 species) and Haptophyta (1 species). Abundance and biomass of phytoplankton were significantly different between euphotic layer (0 to 20m depths) and aphotic layer (50 to 100m depths) (p〈0.05). Minimum and maximum of phytoplankton abundance at euphotic layer were observed in spring (49±14 million/m3) and winter (289±10 million/m3), respectively. Minimum and maximum of phytoplankton biomass at euphotic layer were observed in summer (188±56 mg/m3) and winter (1323±20 mg/m3), respectively. In addition, minimum and maximum of phytoplankton abundance at euphotic layer were observed in western region (100±11 million/m3) and central region (186±27 million/m3), respectively. Mean of phytoplankton biomass at euphotic layer of western and central regions (584±74 mg/m3) was higher than eastern region (473±19 mg/m3). Abundance and biomass of phytoplankton were high in inshore (10m depth) in all seasons and decrease to offshore (100m depth), but the difference of abundance and biomass was not significant between inshore and offshore (p〉0.05). In spring, Bacillariophyta and Pyrrophyta with 40% and 29% of total abundance were dominant phylum at euphotic layer. In fall, Bacillariophyta (57% of total abundance) and Cyanophyta (28% of total abundance) were the first and second dominant phyla. While in summer and winter the predominant phyla was made by Cyanophyta (92% of total abundance) and Bacillariophyta (94% of total abundance) respectively. Species richness in western, central and eastern regions was 119, 141 and 147 respectively. Shannon index was 2.39 and 2.04 at euphotic layer and below photic layer, respectively. Shannon and evenness indices in eastern region was lower than western and central regions. Meanwhile, Shannon index in spring and autmn (2.50 and 2.39) was higher than summer and winter (0.21 and 0.36). In photic layer, dominant species were Stephanodiscus hantzschii Chrysochromulina sp. and Exuviaella cordata in spring. While Oscillatoria sp. was the predominant species in summer. In fall, dominant species contained Thalassionema nitzschioides and Oscillatoria sp. Finally, Pseudonitzschia seriata and Cerataulina pelagica made the most abundance species in winter. The dominant species in the below phoyic layer was very similar to photic layer. The mean abundance of Pseudonitzschia seriata , Oscillatoria sp. and Dactyliosolen fragilissima was higher than other species in all regions of study area (west, middle and east). Seasonal succession of dominant species were under the influence of natural factors such as sunlight, heat, river currents, wind and vertical mixing of water. However it seems that the invasion of ctenophore into Caspian Sea (with change in nutrient levels and decline of phytoplankton predator) and also human activities (i.e. water balance of ships and discharge of sewage) are severely impact on seasonal dominant species, pattern of species composition and relative abundance of species. These changes mainly accompany with appearance of new and harmful species (with the ability of severe proliferation) and displacement of native and dwell species.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Today, calculation of MSY is one of the necessary fisheries management in control and prevention of the fish population reduction and is obtained with different methods. This study has focused on six species of commercial fish, including Tiger-toothed croaker, Javelin grunter, John`s snapper, Indian spiny turbot, Yellowfin seabream and Silver pomfret. The study was done monthly, from January 2007 to March 2008, in three fish landing regions including: Bandar Lengeh, Bandar Abbas and Qeshm Island (Slakh, Basydu and Chahoshrqy). Total 5163 Silver pomfret (Pompus argenteus), 1766 Javelin grunter (Pomadasys kaakan), 2151 John`s snapper (Lutjanus johnii), 3280 Tiger-toothed croaker (Otolithes ruber), 1628 Indian spiny turbot (Psettodes erumei) and the number of 759 Yellowfin seabream (Acnthopagrus latus) were assessed and length biometry has been done, monthly. In this study, two methods were used to determine the maximum sustainable yield (MSY): 1- virtual population analysis (Cohort analysis) 2- use of statistics and information that was estimated with two method, catch prediction and biomass (Standing stock). The results showed that in 2007, MSY value was estimated through catch prediction for Silver pomfret, Tigertoothed croaker, Javelin grunter, John`s snapper, Indian spiny turbot and Yellowfin seabream 1354, 1116, 1099.6, 1045.5, 914.5 and 529.5 tons, respectively. Moreover, this estimation have been done through standing stock for Silver pomfret, Tiger-toothed croaker, Javelin grunter, John`s snapper, Indian spiny turbot and Yellowfin seabream 1215, 633, 1304, 878, 1095 and 441 tons, respectively; and through VPA for Silver pomfret, Tiger-toothed croaker, Javelin grunter, John`s snapper, Indian spiny turbot and Yellowfin seabream 1100, 850, 920, 732.5, 1002.3 and 403 tons, respectively. Amount of biomass (Standing Stock) was estimated for Silver pomfret, Tiger-toothed croaker, Javelin grunter, John`s snapper, Indian spiny turbot and Yellowfin seabream 2530, 1172, 1738, 1689, 1470 and 1110 tons, respectively. In general, by assessing the obtained results for the studied species, exept the fishing prediction results of the Javelin grunter and Tiger-toothed croaker species, which is less valuable due to the low correlation coefficient, it can be stated that except fishing pressure on John`s snapper and Tiger-toothed croaker, in other species studied, fishing conditions are in optimal situation.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: Artemia is considered as live food which can produce cysts and biomass in million tons at hatchery centers or from natural resources. Artemia can be harvested using different variety of methods and has commercial value in aquaculture industry. The quality of produced products has great effect on trading of Artemia at the world. The aim of the present study was to study the hazardous factors in order to increase the quality of Artemia urmiana based on HACCP system. The survived factors were included; biological (bacteria, fungi, yeast, parasite), chemical (Aflatoxine, Organophosphorous, Organocholor, heavy metals, structure of fatty acid, hatchingpercentage), Physical (physical damages, breakdown percentage). The experimental treatments were planned based on two separate groups comprising of without HACCP and the second one, processed with HACCP system. The main hypothesis of current study was to identify the biological, chemical, andphysical hazardous factors of Artemia urmiana based on HACCP system in order toincrease the quality value of A. urmiana cysts. The amount of humidity, protein, lipid, total ash percentage and fatty acid structure in group one (without HACCP sys.) were 45, 28, 10, 18.5 % and in the second group (with HACCP) were 41, 32, 10, 18.2 %. The results of fatty acid profile for both groups indicated in tables 2, 3, 4, and 5. The results showed no significant outcome on quality value of A. urmiana cysts. The concentration of heavy metals (Mn, Cr, Pb, Zn, Ni, Ca, and Cu) in cysts samples of group one was estimated to be 7.4, 0.04, 0.27, 0.98, 0.29, 0.02, 0.18 mg/kg ww. The amount of these elements in cysts samples of group two was 8, 0.03, 0.23, 0.81, 0.21, 0.02, 0.2 mg/kg ww. The results showed no significant outcome in the concentration of metals in group two. The amount of Alderin, Lindin, Alochlar Organophosphorous, and Aflatoxine in samples of group one was 1.25, 0.14, 0.08, and 9.8 ppb and in group two was 1.21, 0.12, 0.05, 8.9, and 0 ppb. There wasn't any significant result in samples, too. Infections of secondary bacteria, gram-positive bacillus and cocci, aspergillus, alternaria, candida were observed in cyst samples of group one. Hatching percentage and efficiency at harvesting time and after keeping for one year, decreased to 11±3 %in cysts samples of group one. It`s concluded that the processing of Artemia urmiana cysts using HACCP system will increase the quality of products and therefore prevent the transmission of secondary infections.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The investigation of the algal bloom effects on Macro benthos abundance and diversity was seasonally carried out in coastline waters of Hormozgan province in 1391. Fourteen stations were selected for sampling; as 8 stations in coast of Bandar Abbas, 3 in Jask Port (east of Hormozgan) and 3 stations in Lengeh Port (west of Hormozgan). Polychaets, oligochaets, mollusks, crustacean and others like nematodes, nemertean’s, foraminifera’s, and ophiuroides were identified. Crustacean with 333950 ind.-2 were dominant group whereas nemertean with 5050 ind.-2 were minimum in density. Results showed that mean abundance of macro benthos was at most in spring (5614±3992 end) -2 and with 1244±380 ind.-2 was at least in autumn. Related results to stations showed that mean abundance in Jask Port and Lengeh Port were more than Bandar Abbas City. Among 8 stations in Bandar Abbas, Langargah with 168±977 ind. -2 was at most and Posht-e- shahr was at least in abundance (82±256 ind. -2). In Lengeh and Jask ports the stations far from coasts showed more abundance than station near coast. Monthly investigation showed that Macro benthos community was much more in April with 1011±6783 ind.-2 than December with 6±28 ind.-2 , respectively. Shannon -Winner diversity index was low (0.61.2) in three stations, Evenness ranged from 0.1 to 0.4 and Margalof ranged from 2 to 4. Among four stations, mean wet weight varied from 12.18±6/95 gr in Jask Port (maximum) to 6.24±3/85gr in Bandar Abbas (minimum) .Seasonally, in spring the wet weight of macro benthos was 15.15±16/32 (maximum) and with 1.43±0.88 gr showed the minimum value in summer. There was a negative correlation between silt and macro benthos abundance and a positive correlation existed between macro benthos community and sand. There was no significant correlation between macro benthos community and TOM. To pay attention to results like diversity, abundance, wet biomass and correlation; it seems that algal bloom has no obvious negative effect on Macro benthos communities.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The project investigates the relationship between the biological parameters (phytoplankton, zooplankton, Macrobenthic and ctenophore- Mnemiopsis leidyi) and environmental parameters, nutrients and environmental pollutants (oil, pesticides, heavy metals, and detergents) in water and sediment, at the southern of Caspian Sea in 2010-2011. Sampling was carried out in four seasons (spring, summer, autumn and winter) and in eight transects perpendicular to the coast (Astara, Anzali, Sefidroud, Tonekabon, Noshahr, Babolsar, Amir Abad and Bandar Turkmen). Samples were collected from the different layers at depths of 5, 10, 20, 50 and 100 meters. The relationship between biological and environmental parameters surveyed through parametric and multivariate statistical methods. Result showed that the annual mean of environmental parameters and nutrients concentration such as water temperature, pH, transparency, DO, ammonium, nitrate, inorganic nitrogen (DIN), organic nitrogen (DON), inorganic phosphorus (DIP), organic phosphorus (DOP) and soluble silicon (DSi) at euphotic layer were 16.70±0.43 (ºC), 8.38±0.01 (m), 5.48±0.05 (ml/l), 1.52±0.06 (µM), 1.80±0.08 (µM), 3.41±0.10 (µM), 43.3±0.9 (µM), 0.32±0.01 (µM), 0.52±0.02 (µM), 8.88±0.22 (µM), respectively. Meanwhile, annual mean of environmental pollutant such as PAHs and OCPs in sediment were recorded 0.88±0.16 (µg/g.dw) and 9.78±2.20 (µg/g.dw), respectively. In addition, annual mean of heavy metals such as Zn, Cu, Ni, Pb and Hg in sediment were obtained 247±46 (µg/g.dw), 29.5±1.5 (µg/g.dw), 49.9±4.9 (µg/g.dw) and 0.179±0.800 (µg/g.dw), respectively. Annual mean abundance of biological parameters namely phytoplankton, zooplankton and M. leidyi (0-20m) at photic layer were 238±17 (million cells/m3), 4808±362 (individuals/m3) and 26±3 (individuals /m3) respectively, and for biomass were 747±60 (mg/m3), 44.3±5.0 (mg/m3), 2.15±0.31 (g/m3). Annual mean abundance of those biological parameters at below of photic layer (50-100m) were 104±35 (million cells/m3), 843±92 (individuals/m3) and 2±1 (individuals /m3) respectively, and for biomass were 412±93 (mg/m3), 9.1±1.0 (mg/m3), 0.15±0.05 (g/m3). Annual mean abundance and biomass of macrobenthic were 5073±1225 (individuals /m2) and 144±73 (g/m2), respectively. Annual mean annual percentage of TOM, Gravel, Sand and Silt-clay were recorded 3.74±0.26, 0.92±0.32 , 22.51±4.97 and 76.67±5.01, respectively. The stratification of water column was strongly based on gradient of water temperature and the phenomenon (difference of temperature between water layers) was more clear in this study compared to previous years. Temperature and biological factors (phytoplankton) were effected on changes of dissolved oxygen at warm and cold seasons summer and winter), but coefficient factor of temperature was higher than biological factors in winter. The nutrients concentration (with the exception of inorganic phosphorus) in different years 2008-2009, 2009-2010 and 2010-2011 increased compared to 1995-1996 (the year of stability of ecosystem). One of the reason attribute to the presence of the ctenophore (M. leidyi) in Caspian Sea after 1999. The annual correlation of phytoplankton abundance and temperature was reversed but seasonal pattern was varied at each season (within a year). In this study, the Caspian Sea contained the conditions of nitrogen limitation (55%) and nitrogenphosphorus limitation (6-43%) as well as phosphate limitation (2-39%) (DIN/DIP〉20) . Inspite of no silica limitation (sufficient concentration of silica) in the Caspian ecosystem, Bacillariophyta was not dominance phylum at whole seasons.It seems that other factors such as the temperature changes of seasons, the effects of predation and feeding of the next chains of the food chain, the difference of the ability in the growth and reproduction, competition (uptake of nutrients) in dfferent groups of phytoplankton and stoichiometry of the nutrients (nitrogen and phosphorus) were caused of non-diatoms dominance at most seasons. As, Pyrrophyta and Bacillariophyta were dominant at spring and winter, respectively and Cyanophyta was pre-dominant at summer and autumn. Multivariate analysis showed the significant correlation between Coppepoda and oxygen and water temperature only. The other gropus of zooplankton did not show any significant correlation with environmental parameters. It might be due to stronger effects of other parameters such as food and predators on different groups of zooplankton at each season and abundance of zooplankton groups indirectly affected by environmental parameters. In this study, Shannon diversity indices of zooplankton and phytoplankton were closer to 1995-96 values and showed diferent trend compared to 2009-2010. However it is not enough reason for recovery of ecosystem in to the stability of Caspian Sea. It is because of other negative evidiance such as strong increasing trend of phytoplankton to zooplankton biomass ratio in all seasons and regions particularly the 2009-2010 and 2010-2011 years compared to 1995-96 (the year of stable ecosystem). In the other word, the balance between the biomass of the first and second of the food chain has been disturbed and the value was much much higher than the year of stable ecosystem in 1995-96. Based on multivariate analyses, there was not significant correlation between zooplankton groups and some edible phytoplankton species, vise versa zooplankton groups consumed some unsuitable species of phytoplankton (based on size, nutritional value, difficulty of digestion and absorption, the potential of toxicity and harmfulness). The lack of expected relationship and routine rules of nutritional between zooplankton and phytoplankton are the more resons of instability in the ecosystem. In current study, dominant group of macrobenthos (polychaeta) observed in depths less than 20 meters which the percentage of silt-clay and sand were 74 and 26, respectively. It seems that this ratio of silt-caly and sand was suitable for their living and accumulation. PCA analysis showed that increasing the percentage of TOM and siltclay accompanied to the decreasing of macrobenthos abundance while increasing the temperature, dissolved oxygen and pH had a positive effect on macrobenthos abundance in most seasons. Increasing the abundance of macrobenthos at all seasons (except spring) would not be a strong indication of improvement of Caspian ecosystem after the ctenophore introduction stress and unfavorable evidence such as low Shannon diversity index observe in the results. Meanwhile, in the present study, Streblospio and oligochaeta (invasive growth and advantage to the food uptake and habitat and sediment seeding) similar to the years of 2008-2009, 2009-2010 still were dominant groups insteade of Gammaridae family (feeding on suspended solids). This means that sediment has a noteworthy amount of organic matter which indicate to the trophic level of ecosystem tend to eutrophy level. The comparison of results on this study to previous studies on biological parameters (phytoplankton, zooplankton and macrobenthos) indicating to the persistence of stress (such as biological and anthropogenic) on their changing population patterns (quantitative relationships between species) and structural patterns (species composition and seasonal succession of dominant species). In other words, many species (both macroscopic and microscopic) of the Caspian Sea are still vulnerable to complications of stressor factors. In order to protection and sustainable exploitation of this worth ecosystem it is necessary to look more serious studies and practical techniques from the relevant organizations in this area.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: With the arrival of the invasive comb jelly Mnemiopsis leidyi in the Caspian Sea in 1991, extensive changes have been occurred. Therefore, this project aims to investigate the comb jelly M. leidyi monitoring and rearing in the southern Caspian Sea in 2013. To survey of M. leidyi and zooplankton abundance and biomass, sampling was carried out during the four seasons at spring, summer, autumn and winter in 4 half-transect (Anzali, Tonekabon, Noshar and Amirabad) and also samples for the ctenophore rearing was done at depths of 5, 10 and 20m. Sampling was performed with a 500 and 100 μ plankton net vertically at layers of 0-5, 0-10 and 0-20 m. 12 aquaria of 50 L volume were designed with salinity of the Caspian Sea to study the breeding and fecundity with aeration. 3 of aquariums with salinity of 9±1pp, 3 with 11±1ppt and 3 of 12±1 ppt filled with Caspian Sea water. Water temperature in each of the three treatments was set in 20±2oC, 23±2^oC and 25±2^oC. 3 of aquaria were set at the salinity of 12.5 ppt and at the same temperature of the Caspian Sea (20, 23, 25^oC) as control. Mean annually Mnemiopsis abundance and biomass were 16.8±1.5 ind.m^3 (139.5±41.1 ind.m^2) and 1.9±0.1 g.m^3. (5.3±0.7 g.m^2). Maximum mean abundance was recorded in autumn with 36.6.7±13.8 ind.m^3 (355.1±103.6 ind.m^2) and maximum biomass was observed in summer of 1.9±0.2 g.m^3(15.0±1.5 g.m^2). Minimum mean abundance was found in spring with 1.3±0.5 ind.m^3 and minimum biomass was in winter of 0.01±0.005 g.m^3. 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. Laboratory studies on M. leidyi reproduction of different sizes at different temperatures showed an average of 12 eggs per day spawning. Maximum spawning rate was registered with 115 eggs per day, for M. leidyi of 46-15 mm (0/7-9/7 g) which increased with increasing size. Average M. leidyi spawning recorded in 11ppt with 25oC was twice in 12ppt (14 eggs. day-1 ) while in salinity of 12ppt of 23^oC the fecundity was two half-times in temperature of 25oC and equal of 20oC. Maximum M. leidyi fecundity was recorded at 23^oC with salinity of 12±1ppt with 22.8±35.5 eggs.day-1. There was a direct regression between size and weight fecundity of M. leidyi, in which fecundity of more than 16 mm length showed the maximum spawning. 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 increasing of M. leidyi 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

Description: Published

Description: The dynamics of Artemia population of Urmia Lake was investigated to provide the technical information, which is necessary for sustainable management of Artemia in Urmia Lake. The study covers different aspects comprising of monthly estimation of Artemia biomass and cysts, annual evaporation of Lake water, average precipitation in catchment areas and also water turbidity in Urmia Lake, during the 2004-2007. Results showed dramatic decline in the Artemia population compared to the previous years, Reduction of average annual precipitation and increased water usage in Urmia Lake catchment area during last decade, has reduced the annual quantities of flowing waters to the Lake. Although the estimated trophic state index (TSI) which indicated the mesotrophic condition during the studied period, therefore, exceeding salinity to higher than the saturated level had adverse effects on phytoplankton growth. Furthermore, nutrient transfer by the rivers to the lake caused to produce of halophilic bacteria and other obtrusive protozoas which has created very unsuitable condition for Artemia grazing. These events confirm the role of salinity as a major environmental factor that affects Artemia resources in their natural habitats. It can be proposed that a method to manage the lake ecosystem and its Artemia population through construction dividers, such as dikes between the north and south parts of the lake to reduce the salinity at some parts of Urmia Lake will be applicable.

Description: Iranian Fisheries Science Research Institute

Description: Published