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  • 1
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/17181 | 4230 | 2016-02-19 11:02:51 | 17181 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-10
    Beschreibung: Source of the Nile Fish farm (SON) is located at Bugungu area in Napoleon Gulf, northern Lake Victoria. The proprietors of the farm requested for technical assistance of NaFIRRI to undertake regular environment monitoring of the cage site as is mandatory under the NEMA conditions. Thus, NAFIRRI undertakes quarterly environment surveys in the cage area covering selected physical-chemical factors i.e. water column depth, water transparency, water column temperature, dissolved oxygen, pH and conductivity; nutrient status, algal and invertebrate communities (zooplankton and macro-benthos) as well as fish community. The first environmental survey was undertaken in February 2011. Results/observations made during the second quarter (April-June 2011) field survey are presented in this technical report along with a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities on the water environment and the different aquatic biota in and around the cages including natural fish communities.
    Schlagwort(e): Aquaculture ; Environment
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 2
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/17202 | 4230 | 2016-02-19 09:21:41 | 17202 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-11
    Beschreibung: Tullow Oil plc is to launch an onshore Early Production System (EPS) of oil drilling rated at 4,000 barrels of oil per day by 2009. The location of the EPS is in the Kaiso-Tonya area of Block 2 Oil Exploration Zone along Lake Albert within the Albertine graben. Tullow Oil plc contracted Environmental Resources Management (ERM) Southern Africa (Pty) Ltd in conjunction with Environmental Assessment Consult Limited (EACL) to undertake an Environmental Impact Assessment (EIA) for pre-construction and operation of the proposed EPS. ERM in association with EACL requested National Fisheries Resources Research Institute (NaFIRRI) to conduct a baseline survey of water quality and invertebrates in River Hohwa. This study was requested as part of an earlier baseline survey conducted at the Kaiso-Ngassa spit oil exploration area in Block 2. It was conducted at five selected sites (Fig. 1 & Table 1) within the Hohwa River basin in the Kaiso-Tonya Exploration Area 2. The study was pertinent because the targeted oil wells for EPS are upstream this river which drains the Kaiso-Ngassa valley into Ngassa lagoon.
    Beschreibung: Environmental Assessment Consult Limited (EACL)
    Schlagwort(e): Environment ; Fisheries
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 3
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/17144 | 4230 | 2016-03-01 14:25:04 | 17144 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-10
    Beschreibung: Following the commencement of construction works of a 250 MW hydropower plant at Dumbbell Island in the Upper Victoria Nile in September 2007, BEL requested NaFIRRI to conduct continuous monitoring of fish catches at two transects i.e. the immediate upstream transect of the project site (Kalange-Makwanzi) and the immediate downstream .transect (Buyala-Kikubamutwe). The routine monitoring surveys were designed to be conducted twice a week at each of the tWo transects. It was anticipated that major immediate impacts were to occur during construction, and these needed to be known by BEL as part of a mitigation strategy. For example, the construction of it cofferdam could be accompanied by rapid changes in water quality and quantity downstream of the construction. These changes in turn could affect the fish catch and would probably be missed by the quarterly monitoring already in place. Therefore, a major cbjective of the more regular and rapid monitoring was to discern immediate impacts of construction activities by focusing on selected water quality parameters (total suspended solids, water conductivity, temperature, dissolved oxygen and pH) and fish catch characteristics (total catch, catch rates and value of the catch)
    Beschreibung: Prepared for Bujagali Energy Limited (BEL)
    Schlagwort(e): Environment ; Fisheries
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 4
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20301 | 4230 | 2016-03-05 18:03:06 | 20301 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-09
    Beschreibung: Source of the Nile Fish farm (SON) is located at Bugungu area in Napoleon Gulf, northern LakeVictoria. The proprietors of the farm have a collaborative arrangement with NaFIRRI to undertake quarterly environment monitoring of the cage site as is mandatory under the NEMA conditions. The monitoring surveys cover selected physical-chemical factors i.e. water column depth, water transparency, water column temperature, dissolved oxygen, pH and conductivity; nutrient status, algal and invertebrate communities (micro-invertebrates/zooplankton and macroinvertebrates/macro-benthos) as well as fish community. The second quarter survey for the calendar year 2015, which is the subject of this report, was undertaken in June 2015.Results/observations made are presented in this technical report along with a scientificinterpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and aquatic biota.
    Schlagwort(e): Aquaculture ; Environment
    Repository-Name: AquaDocs
    Materialart: monograph
    Format: application/pdf
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    Format: 56
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  • 5
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20249 | 4230 | 2016-03-01 14:17:26 | 20249 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-08
    Beschreibung: Source of the Nile (SON) Cage Fish farm is located at Bugungu in Napoleon Gulf, northern Lake Victoria, near the headwaters of the River Nile. NaFIRRI has, through a Public-Private collaborative partnership with SON management, undertaken quarterly monitoring of the cage fish farm since 2011. The objective of the environment monitoring is to track possible environment and biological changes as a result of fish cage operations in the area. The agreed study areas cover selected physical-chemical parameters i.e. water depth, transparency, column temperature, dissolved oxygen, pH and conductivity; nutrient status; and biological parameters i.e. algae, zooplankton, macro-benthos and fish communities. The fourth quarter survey, which is the subject of this report was undertaken during December 2015. Results/observations made are presented in this technical report along with a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and aquatic biota.The present report presents field observations made for the fourth quarter survey undertaken in December 2015 and provides a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and the different aquatic biota in and around the fish cage site.
    Schlagwort(e): Aquaculture ; Environment
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 6
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20302 | 4230 | 2016-03-06 09:41:03 | 20302 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-09
    Beschreibung: This monitoring survey No. 11 undertaken between 4th and 9th September 2012 is the second one to be conducted after completion of construction of Bujagali HydropowerDam. Two pre-construction baseline surveys in April 2000 and April 2006 were conducted and during construction phase, eight monitoring surveys (September 2007,April 2008, April 2009, October 2009, April 2010, September 2010, April 2011, September 2011) were conducted.
    Beschreibung: Carried out on behalf of Bujagali Energy Limited (BEL)
    Schlagwort(e): Environment ; Fisheries
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 7
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20643 | 4230 | 2018-10-21 09:46:56 | 20643 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-11
    Schlagwort(e): Aquaculture ; Environment
    Repository-Name: AquaDocs
    Materialart: monograph
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    Format: 47
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  • 8
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20672 | 4230 | 2016-05-21 17:58:57 | 20672 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-11
    Beschreibung: The results reported on were from a monitoring survey No. 9 undertaken between 9th and 12th September 2011 during construction period of the Bujagali Hydropower Project (BHPP). Two pre-construction, baseline surveys in April 2000 and April 2006 were conducted and so far, during construction phase of the project, eight monitoring surveys have been undertaken i.e. in September 2007, April 2008, April 2009, October 2009, April 2010, September 2010, April 2011 and the present one, in September 2011. Since 2009 biannual monitoring surveys have been conducted at an upstream and a downstream transect of the BHPP with emphasis on the following aspects:water quality determinants biology and ecology of fishes and food webs fish stock and fish catch including economic aspects of catch and sanitation/vector studies (bilharzias and river blindness)in addition to the above mentioned studies, a soil pH survey was undertaken on 15th October 2011 in the area behind the reservoir whose filling started a week earlier. The findings of pH status in the catchment of the dam are also contained in this report.
    Schlagwort(e): Environment ; Fisheries
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 9
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20933 | 4230 | 2016-07-24 07:50:29 | 20933 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-13
    Beschreibung: Kariba weed (Salvinia molesta) is an invasive alien waterweedthat was first recorded in Uganda in sheltered bays of LakeKyoga in June 2013. This waterweed has become a commonfeature on Lake Kyoga and its associated rivers, streams andswamps, and has spread to other lakes notably Kwania and Albert in addition to Lake Kimira in Bugiri district.
    Schlagwort(e): Environment ; Fisheries
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 10
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20070 | 4230 | 2016-02-23 09:46:15 | 20070 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-07
    Beschreibung: Source of the Nile Fish farm (SON) is located at Bugungu area in Napoleon Gulf, northern Lake Victoria. The proprietors of the farm requested for technical assistance of NaFIRRI to undertake regular environment monitoring of the cage site as is mandatory under the NEMA conditions. As the SON is a key collaborator/client of the institute, NAFIRRI agreed to undertake the assignment subject to facilitation by the client. The institute agreed to conduct quarterly surveys of key environmental parameters at the site including selected physical-chemical and biological factors, nutrient status, column depth, water transparency and sedimentation. Samples and field measurements were to be taken at 3 sites: within and/or close to the fish cages (WIC), upstream (USC) and downstream (DSC) of the cages. The first environmental monitoring survey was undertaken in February 2011; the second in May 2011 and the third in September 2011. The surveys cover physical-chemical parameters, nutrient status, invertebrate and fish communities. The present report presents field observations made for the fourth quarter survey undertaken in November 2011 and provides a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and the different aquatic biota at and around the cage site including natural fish communities.
    Schlagwort(e): Aquaculture ; Environment
    Repository-Name: AquaDocs
    Materialart: monograph
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    Format: 38
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  • 11
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20462 | 4230 | 2016-04-15 11:44:56 | 20462 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-10
    Beschreibung: The specific objectives were to:WATER QUALITY1. To measure the water physical variables as indicators of environmental conditions in the upstream and downstream transects of Kalange (1) and Buyala (2), respectively,2. To determine the concentrations of total suspended solids as a major constituent likely to be released into the waters at any time during the construction activities, by comparing the concentrations at the two transects.FISH CATCH1. To follow up trends in fish catch as construction activity progresses, and to precision of the estimate;2. To estimate the prevailing fish catch rates, total fish catches and the total value of the fish catch to the local fishers at the two transects.
    Beschreibung: On title page: Environmental and Social Impact Monitoring of the Bujagali Hydropower Project (BHPP), Uganda Fisheries Component
    Schlagwort(e): Environment ; Fisheries ; Limnology
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 12
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/20440 | 4230 | 2016-04-07 07:51:42 | 20440 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-08
    Schlagwort(e): Environment ; Fisheries
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 13
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/26053 | 4230 | 2018-10-21 09:52:16 | 26053 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-24
    Beschreibung: National Fisheries Resources Research Institute (NaFIRRI) undertakes quarterly monitoring of the water environment at Source of the Nile (SON) fish farm. The activity which is through a collaborative arrangement between SON fish farm and NaFIRRI aims at assessing possible changes in the water environment at SON cage area. The fish rearing activity at SON fish farm involves keeping fish in cages often under high stocking densities and feeding them on artificial feeds that are not the natural food eaten by wild fish. Cages being open systems means that all wastes such as faeces, uneaten feed and fish excretes such as ammonia are shed into the water column (Fernandes et al., 2001). The consequence is increased nutrient input which may result into high algal growth (bloom). Although this may mean more food available to primary consumers such as zooplankton, blooms caused by blue-green algae may be harmful as certain species are associated with production of toxins. In addition, the degradation of excessive phytoplankton biomass can lead to anoxic conditions in sediments underlying the cages thus changing the abundance and composition of the resident fauna. Napoleon Gulf being a shallow bay at the exit of River Nile from Lake Victoria harbours a wide variety of wild fish species that are cherished by riparian human populations. The wild fishes living close to cages are bound to be affected by activities associated with this method of fish farming. Cage farming is likely to affect the presence, abundance, diet and residence time of organisms in given vicinity (Carss, 1990; Dempster et al., 2002). Floating structures including cages may act as Fish Attracting Devices (FADs) and most pelagic fishes are known to be strongly attracted to floating objects (Freon and Dagorn, 2000; Castro et al., 2002). Wild fish could be attracted to these sites by for example plenty of food available to the cultured fishes (Bjordal & Skar, 1992). In the process, other ecological interactions between cultured and wild fish may be possible. Wild fish may also be instrumental in cleaning the environment close to the cages through eating any excess uneaten food left by cultured fishes. Caged fish under crowded conditions is susceptible to waterborne diseases and could infect wild fish or vice versa. While diseases breaking out among cultured fishes may be controlled through treatment, the wild fishes cannot undergo treatment and may thus spread diseases to other fishes, hence affecting yields from capture fishery. Furthermore, escape of cultured fish may cause genetic dilution hence decreasing genetic diversity of fish. These and other possible impacts of cages on the water environment may consequently result into conflicts 2 with other resource users especially due to deteriorating water quality and effect on wild fishes, consequently affecting the cage aquaculture industry. Therefore, the following were established as key parameters to be monitored: water temperature, dissolved oxygen, pH, conductivity, water transparency, total suspended solids, nutrient status, algae, zooplankton, benthic macro invertebrates and fish communities. The present report presents field observations made at the two cage sites of Source of the Nile fish farm including upstream, downstream and reference points, for the second quarter (April to June) undertaken in June 2017. The report provides a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities on the water environment and the different aquatic biota in and around the fish cage site.
    Schlagwort(e): Aquaculture ; Environment ; Limnology ; Pollution
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 14
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/26063 | 4230 | 2018-10-21 11:13:50 | 26063 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-24
    Beschreibung: The monitoring of water quality and biotic communities at Source of the Nile (SON) fish farm area, for quarter 4 (October – December) was undertaken in December 2017. The activity aimed at assessing possible changes in the water environment at SON cage area. The following parameters were assessed: water physico-chemicals and nutrients, algae, zooplankton, benthic macro invertebrates, and fish communities. Total depth was above 5.0 m (range: 5.63 – 9.74 m) at all sampled points and decreased towards the downstream of cages. Water transparency ranged from 1.26 – 1.48 in the cage area and 1.08 to 1.34 m away from the cages. Within the cage area, Dissolved Oxygen ranged from 5.7 – 6.4 mg/L at the surface, and 5.1 – 6.4 mg/L at the bottom, while in the non-cage areas, the range was 5.5 – 7.5 mg/L at the surface and 2.6 – 7.0 mg/L at the bottom. Temperature ranged from 27.0 – 28.0 o C at the surface and 25.5 – 27.5 o C at the bottom waters for all sites, and were within the optimal range (25 – 32 o C). pH in both surface and bottom waters was above 7.0 (range: 7.5 – 9.2) at all sites. Conductivity within cage area ranged from 100.5 – 102.6 μScm-1 in surface water and 101.8 – 112.1 μScm-1 in bottom water. In the non-cage areas conductivity ranged from 11.0 – 104.4 μScm-1 in surface water and 100.2 – 110.0 μScm-1 at the bottom. Ammonium nitrogen concentration during December was less than 0.02 mg/L at all sites (0.007 – 0.018 mg/L within the cage sites, and 0.012 – 0.019 mg/L in the non-cage sites). Nitrite nitrogen ranged from 0.002 – 0.169 mg/L in the cage area, and 0.003 – 0.057 mg/L in the non-cage areas. Similar to previous records of June and September 2017, nitrate nitrogen concentration generally increased towards the downstream site, being lowest at RPT (0.041 mg/L) and highest at DSC (0.204 mg/L). Soluble reactive phosphorus was less than 0.005 mg/L at all sites, and varied within narrow margin (range: 0.003 – 0.0048 mg/L in cage sites, and 0.0032 – 0.0047 mg/L in non-cage sites). The TP concentration ranged from 0.085 – 0.107 mg/L in the cages, and 0.090 – 0.118 mg/L in the non-cage sites and was higher than recorded in September (0.038 – 0.044 mg/L in the cages and 0.04 to 0.109 mg/L away from cages). Total nitrogen concentration was in the range of 0.138 – 0.553 mg/L within cage area and 0.421 – 0.513 mg/L in non-cage areas. The concentration of TSS ranged from 0.76 – 4.33 mg/L in the cage area and 0.57 – 2.76 mg/L in the non-cage areas. The phytoplankton community was composed of blue-green algae, green algae and diatoms, dominated by blue-green algae. The abundance of algae was higher in the non-cage areas (mean:7.20 ± 2.14 mm3L-1, Range: 5.15 – 10.20 mm3L-1) than recorded in the cage areas (mean: 6.0 ± 0.71 mm3L-1, Range: 5.30 – 6.98 mm3L-1), similar to observations of September 2017 (〈 5 mm3L1 within the cages and 〉5.6 mm3L-1 in the non-cage sites). At all sampled points, blue-green algae contributed 〉70% of total abundance. Total zooplankton abundance ranged from 982,213 – 1,310,830 ind.m-2 in the non-cage sites, and 740,601 – 1,503,130 ind.m-2 in the cage areas. Similar to observations of September 2017, the upper cage site (WIC3 and WIC4) presented lower zooplankton abundance (mean: 788,954 ± 68,381 ind.m-2) when compared to the lower cage site with mean abundance of 1,128,232 ± 530,186 ind.m-2. Like in the previous sampling periods, copepods were the numerically dominant group (92.69 – 97.22 % of total zooplankton abundance) at all sampled points, with no major differences between cage and non-cage areas. The high abundance of copepods was attributed to the abundance of the juvenile stages (copepodites and Nauplius larvae) which contributed 83.72 – 92.78% of the total zooplankton abundance and this was mainly due to the Nauplius larvae (66.4 – 83.2 %). Cladocera relative abundance ranged from 0.32 – 3.98% while that of rotifers ranged from 1.55 – 3.74%. The macro-benthic community comprised molluscs, annelids and arthropods. Taxa richness ranged from 5 – 11 taxa in the cage area, and 7 – 9 taxa in the non-cage areas. The abundance of benthic invertebrates within the cage area ranged from 1,134 – 2,416 ind.m-2 and this was higher than previously recorded in September (294 – 1,415 ind.m-2). In the non-cage sites abundance was in the range of 420 – 3,992 ind.m-2. Oligochaete annelids which are reported to be very tolerant to pollution contributed 0 - 28 % of the abundance of benthos at cage sites and 3 - 20% at the non-cage sites. Diptera made the greatest contribution at almost all sites, with the percent abundance being higher in non-cage sites (40 – 86%) than what was recorded in the cage sites (37 – 82%). Chironomus spp. and Chaoborus sp. were the main contributors to the observed Diptera abundance at all sites. Six fish species, including haplochromines (Nkejje) as a single species group, were recorded in the vicinity of the cages during December 2017. Five fish species were recorded from upstream the cage site, four species from within cage area, and two species from downstream the cages. Overall mean catch rates were 1.8 fish/net/night and 148.6g/net/night compared to 1.7 fish/net/night and 175.4g/net/night recorded in September 2017. By weight, catch rates in December 2017 were highest upstream the cage site (312.1g/net/night) and also by numbers (3.1 fish/net/night). Four species of haplochromines were recorded in the vicinity of the cages during the survey of December 2017 compared to six species recorded in September 2017. The overall catch rate for the haplochromines, in December 2017 was 1.7fish/net/night and 27.5g/net/night compared to 3.4 fish/net/night and 62.3g/net/night recorded in the previous survey of September 2017. Among the fish species examined during December 2017 survey, most of the haplochromine cichlids (88.9%) were mature but only 50% breeding. Only one specimen of L. niloticus was mature and breeding. All S. afrofischeri and S. victoriae specimens examined were mature and in breeding condition while M. kannume was immature. The diet of fishes encountered comprised mostly of fish and insects, which are known natural foods of the fish species. Infection by fish parasites during the survey of December 2017 was not noticed in any fish recorded from the experimental gillnets. The overall observation on concentrations of nutrients, levels of physico-chemical variables, and biotic communities indicated minimal impact of cages on water quality. The farm should therefore continue adhering to the best environmentally sustainable aquaculture practices, especially continuing with fallowing or rotation of cages to allow resident organisms maintain their natural population densities, distribution and community structure in the area; reducing excess uneaten feed and other suspended materials which would impact on nutrient status and biota; as well as wise use of any chemicals in the area.
    Schlagwort(e): Aquaculture ; Environment ; Limnology ; Pollution
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 15
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/17354 | 4230 | 2016-02-19 08:57:04 | 17354 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-11
    Beschreibung: Source of the Nile Fish farm (SON) is located at Bugungu area in Napoleon Gulf, northern Lake Victoria. The proprietors of the farm and the National Fisheries Resources Research Institute (NaFIRRI) have an established collaborative arrangement where NaFIRRI provides technical back-stopping to enable quarterly environment monitoring of the cage site; a mandatory requirement of the National Environment Management Authority (NEMA). The agreed studyareas are physical-chemical factors (water depth, water transparency/secchi depth, water temperature, dissolved oxygen, BOO, pH, conductivity), and selected nutrients), algal community (including primary production), aquatic invertebrates (zooplankton and macrobenthos) and the fish community. This report presents field observations made during the third quarter (July-September) field survey undertaken during August 2014; along with scientificinterpretation and discussion of the results in reference to possible impacts of the cage facility to the water environment quality and aquatic biota.
    Schlagwort(e): Aquaculture ; Environment ; Source of the Nile Fish Farm (SON)
    Repository-Name: AquaDocs
    Materialart: monograph
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  • 16
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/17362 | 4230 | 2016-02-23 09:13:07 | 17362 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-11
    Beschreibung: Source of the Nile Fish farm (SON) is located at Bugungu area in Napoleon Gulf, northern Lake Victoria. The proprietors of the farm requested for technical assistance of NaFIRRI to undertake regular environment monitoring of the cage site as is mandatory under the NEMA conditions. NAFIRRI agreed to undertake quarterly environment surveys in the cage area covering selected physical-chemical factors Like water column depth, water transparency, water column temperature, dissolved oxygen, pH and conductivity; nutrient status, algal and invertebrate communities (microinvertebrates/zooplankton and macro-invertebrates/macro-benthos) as well as fish community. The first quarter survey was undertaken in February 2011; the second in May 2011 and the third quarter survey, which is the subject of this report, in September 2011. Results/observations made are presented in this technical report along with a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and aq-uatic biota, including the natural fish community at and around the cage site.
    Schlagwort(e): Aquaculture ; Environment
    Repository-Name: AquaDocs
    Materialart: monograph
    Format: application/pdf
    Format: application/pdf
    Format: 40
    Standort Signatur Erwartet Verfügbarkeit
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  • 17
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    National Fisheries Resources Research Institute (NaFIRRI) | Jinja, Uganda
    In:  http://aquaticcommons.org/id/eprint/17285 | 4230 | 2016-02-23 09:08:03 | 17285 | National Fisheries Resources Research Institute, Uganda
    Publikationsdatum: 2021-07-11
    Beschreibung: The first environmental survey was undertaken in February 2011. The survey covered physical-chemical parameters (Water depth, water transparency, water column temperature, dissolved oxygen, pH and conductivity), nutrient status, algal and invertebrate communities (algae, micro-invertebrates/zooplankton and macro-invertebrates/macro-benthos) and the fish community. This report presents the field observations made and provides a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and the different aquatic biota at and around the cage site including natural fish communities.
    Schlagwort(e): Aquaculture ; Environment
    Repository-Name: AquaDocs
    Materialart: monograph
    Format: application/pdf
    Format: application/pdf
    Format: 31
    Standort Signatur Erwartet Verfügbarkeit
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