A new procedure for canning of squids

A new canning procedure for squid mantles aimed at increasing the fill and retaining the sweet flavour of squids was evolved. In the new method, after blanching smaller mantles are inserted inside bigger ones to reduce voids and thus increase the fill to 56% and above as compared to 46% when packed as rings. In addition, spent blanching medium containing desirable flavour constituents of squid was modified and used as covering medium which increased the flavour of canned product.

Smoking of shrimp and fish from coastal village of north-west Bangladesh

Traditional smoking of mixed shrimp species is a method of preservation in coastal region of Bangladesh. Besides traditional smoked shrimp, attempt had been made to produce smoked shrimp from brown shrimp, Metapenaeus monoceros and fish from mugil, Liza parsia and the quality of smoked product was found good very on the basis of physical properties, proximate composition and mineral contents of the products.

The biology, ecology and impact of the Nile perch, Lates niloticus in lakes Victoria, Kyoga and Nabugabo and the future of the fisheries

Nile perch (Mputa), Lates niloticus was introduced into Lakes Victoria and Kyoga from lake Albert to increase fish production of these lakes by feeding on and converting the small sized haplochromines (Nkejje) which were abundant in these lakes into a larger table fish. It was, however, feared that Nile perch would prey on and deplete stocks of the native fishes and affect fish species diversity. Nile perch became well established and is currently among the three most important commercial species. It is presently the most important export fish commodity from Uganda. Considerable changes have taken place in fishery yield, and in life history characteristics of the Nile perch itself since the predator got established in Lakes Victoria and Kyoga.

Comparison the nutritional value of cultured Penaeus vanname with marine shrimps Penaeus merguiensis and Penaeus semisulcatus

The purpose for which this study was intended wasto compare nutritive value among the farmed Vannamei, sea Green Tiger and Banana shrimps native to the PersianGulf. To provide the samples of farmed shrimps at the end of the farming season (Oct. 23rd through Nov. 22nd of 2011), we chosen one farm of the Holleh Shrimp Farming, from which 100 shrimps were randomly selected. From among these 100 shrimps, 3 to 5 ones were taken to conduct an analysis upon. Further, to obtain the Banana and Green Tiger shrimps sampling was done at the fishing season (July 23rd through Aug. 22rd of 2011) at Halileh Fishing Wharf located in Bushehr Fishing Harbor and also Bandar Abbas Wharf. The samples obtained were immediately kept in the ice powder. After some biometric tasks done upon them, they were at the shortest possible time transferred to a laboratory where they went through various experiments to determine their content of raw protein, fat, ash, moisture, various fatty acids and their types, cholesterol, vitamins A and E, and such mineral elements as iron and calcium. All the experimentswere carried out three times to establish confidence in the results to be obtained. Findings of the comparison showed the content of raw protein, fat, moisture, and ash of, respectively, 23.233%, 600%, 73.077% and 2.500% for the Vannamei samples, of 22.717%, 427%, 74.133% and 1.826% for our Banana shrimps and of 17.377%, 430%, 79.866% and 1.313% for the Green Tiger samples. A total of 24 fatty acids for the Vannamei shrimps and 27 for the Banana and Green Tiger were detected. SFA of the Banana shrimps was 368.45 mg/100g (51.76%), while those of the Vannamei and Green Tiger samples were observed, respectively, 363.54 mg/100g (37.26%) and 296.06 mg/100g (49.12%).A similar measurement for MUFA content of the three types of our samples revealed 243.85mg/100g (24.9%) for the Vannamei, 203.177 mg/100g (33.76%) for the Green Tiger and 179.033 mg/100g (25.14%) for the Banana shrimps. The content of PUFA unsaturated fatty acids in the Vannamei, 131 Green Tiger and Banana samples were, respectively, 370.660 mg/100g (37.84%), 101.573 mg/100g (16.9%) and 163.733 mg/100g (23.1%). Further, the comparison found a omega-3-fatty-acids total of 151.747 mg/100g(15.51%) for the Vannamei, 57.123 mg/100g (9.54%) for the Green Tiger and 130.460 mg/100g (18.46%) for the Banana species under study.

Determination of biological characteristics and blood groups of hilsa shad (Tenualosa ilisha) in the north of Persian Gulf (Bushehr coastal waters)

Hilsa shad, Tenuolosa ilisha, belongs to Clupeidae family and Alsinae subfamily is an euryhaline pelagic and anadromous species living in marine and freshwater waters. Regarding to study the biological characteristics of this species, this study was carried out in the Northern Persian Gulf within Bushehr province waters during years 2006-7. A total of 344 specimens were collected and transported to the laboratory for further different biological measurements consist of: reproduction (GSI, fecundity, maturity stages), feeding (stomach contents, food preference ...), aging; 58 morphometric and ٧ meristic measurements. The results indicate that minimum, maximum and mean body weight are 203, 953 and 481.35±147.64 g, respectively and this values for total length are 26.5, 45.1 and 35.99±3.98 cm. For food regimes, the most abundant phytoplankton foods belong to Bacillariophyta (83.74٪) and zooplanktons of Arthropoda (51٪). The mean RLG was measured about 1.53±0.22 and the mean feeding intensity was about 51.79±38.13. Also, the aging of studied fishes showed that they have 2 to 4 years and most of the samples had 2+ years. The reproduction studies showed that Indian shad is a batch spawner species. The average gonadosomatic index (GSI) is 1.64±1.382 and the main spawning season was determined for April-May.

The history of fish communities, biodiversity and environment of Lake Victoria and the lessons learnt

The first fishery survey of Lake Victoria was conducted between 1927 and 1928 (Graham 1929). Atthat time, the lake had a diverse fish fauna and the fishery was dominated by two endemic tilapiine cichlids; Oreochromis esculentus (Graham 1929) and O. variabilis (Boulenger 1906). There were a number of other species such as Protopterus aethiopicus Heckel 1851, Bagrus docmac (Forsk.) 1775, Clarias gariepinus (Burchell), Barbus species, mormyrids, Synodontis spp, Schilbe intermedius (Linn.) 1762 and Rastrineobola argentea Pellegrin, 1904 that were also abundant in the lake most of which made a significant contribution to the fishery (Graham 1929, Worthington 1929, 1932, Kudhongania & Cordone 1974). Haplochromine cichlids were represented by at least 300 species more than 99% of them endemic (Greenwood, 1974; Witte et al., 1992 a & b). The fishery of Lake Victoria was similar to that of lakes Kyoga and Nabugabo (Worthington 1929; Trewavas 1933; Greenwood 1965, 1966; Beadle 1962, 1981). There were also important fisheries on the inflowing rivers of Lake Victoria, the most important of which were Labeo victorianus and Barbus altianalis (Cadwallader 1965). The small sized species notably Rastrineobola argentea and haplochromines cichlids were not originally commercially exploited.

Human activities and interests within and around lakes of the Victoria and Kyoga basin and their consequences to sustainable fish production

Of all the great lakes, Lake Victoria has the highest population concentration on its fringes. This has resulted into serious human impacts on the ecosystem through intense agricultural activities (cultivation, livestock and over fishing), sporadic settlements, urbanization and industrial establishments. The consequences have been loss of animals and plant life, deforestation and general land degradation, pollution, loss of water quality and clean air. Aquatic life has become endangered and less guaranteeing to continued fish production. Awareness workshops and general talks have been done to a few selected communities by the lakes landing sites and in the catchment area to mitigate the deteriorating environmental conditions. Naturally the situation calls for reversal to the increasing stress of the ecosystem. As a result, every water body surveyed put forward some mitigation suggestions

The biology, ecology, population parameters and the fishery of the Nile tilapia, Oreochromis niloticus (L)

Oreochromis niloticus (the Nile tilapia) and three other ti1apine species: Oreochromis leucostictus, Tilapia zi11ii and T. rendallii were introduced into Lakes Victoria, Kyoga and Nabugabo in 1950s and 1960s. The source and foci of the stockings are given by Welcomme (1966) but the origin of the stocked species was Lake Albert. The Nile tilapia was introduced as a management measure to relieve fishing pressure on the endemic tiapiines and, since it grows to a bigger size, to encourage a return to the use of larger mesh gill nets. Ti1apia zillii was introduced to fill a vacant ,niche of macrophytes which could not be utilised' by the other tilapiines. Tilapia rendallii, and possibly T. leucosticutus could been introduced into these lakes accidently as a consquence of one of the species being tried out for aquaculture. The Nile perch and Nile tilapia have since fully established themselves and presently dominate the commercial fisheries of Lakes Victoria and Kyoga. The original fisheries based on the endemic tilapiines O. escu1entus and o. variabilis have collapsed. It is hypothesized that the ecological and limnological changes that are observed in Lakes Victoria and Kyoga are due to a truncation of the original food webs of the two lakes. Under the changed conditions, O. niloticus to be either playing a stabilizing role or fuelling nutrient turnover in the lakes. Other testable hypotheses point to the possible role of predation by the Nile perch, change in regional climate and hydrology in the lake basins.

Survey of fish factory agents on Lake Victoria, Uganda

The purpose of the survey was to gain a better understanding of the role of factory agents in buying fish and setting prices, and of their place and role in fisheries co-management on Lake Victoria, Uganda.

Generation, flow and utilisation of information on the regional fish trade

The purpose of the study was to provide an in-depth understanding of information generation, flow and utilization within Uganda’s regional fish trade. The study was carried out at district headquarters, border points, landing sites and border markets, involving DFOs, Customs Officials, BMU executives and market managers.

Capture fisheries in Uganda: why Bujagali hydro-power project and ecological monitoring?

Human use of water resow-ces in Uganda has grown and intensified along with population growth and increasing demand to meet the diverse human needs. In the case of Uganda's rivers, the main uses include fisheries, hydropower generation, abstraction for potable water supply, discharge of sewage and navigation. All these uses can disrupt the integrity of the aquatic ecosystem and may affect the survival of the diversity of organisms. In consideration of the need to increase electricity to meet demand, the Bujagali Hydro-power Project (BHPP) and the National Environment Management Authority (NEMA) recognised the importance of safeguards to mitigate impacts of the project. The National Fisheries Resources Research Institute (NaFIRRI) was assigned the role of providing baseline information on the aquatic ecosystem of the Upper Victoria Nile and to follow up the findings with a monitoring framework during construction and post-commissioning phases.

The socio-economic effects of trawling on the present day fishermen

1. The introduction of trawlers to Lake Victoria to harvest fish will have far reaching effects on the men (and women) presently engaged in the fishery, on the diet of the nation as a whole. 2. However, the whole concept of trawling is so different to present techniques and the scale of operation so great, that disruption to the socio-economy of many people is possible. 3. The sociological studies outlined below will assist the governments in the formulatlon of policies aimed at minimising disruptive effects on the lives of many individuals.

Increase in fish production achieved by stocking exotic species (Lake Kyoga, Uganda)

The Lake Kyoga complex lies towards the north of Uganda, at 311 altitude of 3,400 feet, between 10 and 2° north of the Equator. The lake is extremely elongate and digitate, shallow (1 metre-7 metres), and almost all the coast-line is swampy, with many papyrus beds. Floating islands of sud are a feature. At its eastern extremity, it breaks up into many swampy, isolated lakes. The Nile from its source at Jinja enters Lake Kyoga on its southern side, and leaves the lake at its western extremity, and winds on through to Lake Albert and the Sudan. The Kyoga/Salisbury /Kwania complex covers 2,354 sq. km. of water. Geologically, the lake is a series of flooded river valleys, probably resulting from the uplifting of the western edge of the basin in the Pliocene and the Pleistocene ages aud the endemic fish fauna is very similar to that of Lake Victoria, although Kyoga has not developed the species flocks of haplochromis which characterise the larger lake. The Victoria fauna extends down-stream of Lake Kyoga to the Murchison Falls on the Nile, which forms an almost complete barrier between Kyoga and the typical nilotic fauna of the Nile below Murchison and Lake Albert.

Annual Report of the Game and Fisheries Department for the year ended 31st December, 1953

Summary of fish production on main lakes of Uganda 1953, consumption of fish in Uganda 1953, imports and exports of fish, including reports from the different regions Fisheries by Regions (1) Lake Victoria (2) Lake Albert (3) Lake Kyoga and Waters of Eastern Uganda Lakes George, Edward, Fish Farming, Dams and miscellaneous minor waters. It includes information on: Angling which includes Trouting, Nile Perch fishing and Tiger Fishing, Ripon Falls Barbel and Tailpiece.

The toxicity of four insecticides and a herbicide under tropical conditions

The toxicities of four insecticides and a herbicide to Tilapia macrochir were tested in the laboratory. The 24 hour LC50's were estimated as follows: Endrin 20% ,0.008 ppm; Lindane 5% granules, 4.6 ppmm; Synexa 50 (HCH) 50%), 5.6 ppm; Synex 25 (HCH 25%), 14.8 ppm; TOK herbicide (Nitrofen), 100% survival for 24 hours at 100 ppm. These estimates agree with results obtained by other workers elsewhere in the world. The laboratory determination of toxicity is important in estimating the direct effects of poisonous substances on fish, but other indirect effects may result from their use. These should be investigated in the field.