A synopsis of the traditional fishing gears used in artisanal fisheries along the upper part of the Cross River

Artisanal fishery is the main type of fishing practised occupationally by the fishermen along the upper sectors of the Cross River. No form of mechanised fishing has so far been introduced to the fishermen in these areas. This study has attempted to find out the different gears used, when and where used along the main river channel, its tributaries and flood plains. An effort has also been made to provide some information on the types of fishes caught with the different gears. Recommendation for effective management are also advanced

Fishing gears survey of Lake Chad

The paper reports on a survey on gear assessment for the three intensive fishing seasons in Lake Chad (Nigeria). These seasons coincide with the flood period (Nov-Feb), the receding (March-June)and the recession period (July-September 2001). During this year the questionnaires were requested to ten fishers in each of the selected fishing islands. In the flood season, identified fishing gears on the lake included baited and un-baited Malian traps which constituted about 35% of the total gears recorded. While Ndurutu and Heri (Kung)traps represented, each, 3.2% of the total. About 15.9% of fishers employed hook lines of various length and sizes: Another 15.9% of fishers mounted fish fences (Dumba) during the season. Those that employ seine net accounted for about 11.1% while 9.5% use gill nets.The species belonging to the Cichilidae, Claridae and Osteoglossidae families dominated fish catches. During the receding period, hook lines and fences (Dumba) (6.20%) were found to be predominantly used on the lake due to reducing water level, followed by gill net and draw net which accounted for 17.9% and 16.1 % respectively. During the lake recession only two groups of active gears were recorded. Sixty percent of fishers use combined seine net with cutlass and scoop net, while 40% use to combine only cutlass with kabara net. Fish fences (Dumma)during the flood season were mounted with giant Malian traps of abut 1.5m by 0.5m diameter, covered with net of mesh size (6.3mm-25mm).Each Dumba contained between 150 and 2000 of such traps. Larger number of species was recorded from seine net followed by gill nets and the l kilometre multi mesh fleet drift net. The use of seine net and cutlass known as Genima was predominant during the lake recession

Fishing gears diversity in Sunamganj, Haor region within CBRMP's working area

This book is a research output on fishing gears used in the beels from Sunamgan Haor areas under the initiative of the Community Based Resource Management Project (CBRMP) of LGED and WorldFish. It presents a collection of gears recorded in the CBRMP project area during monitoring conducted by WorldFish from 2008 to 2012. The book contains a total of 63 gears found in Sunamganj haor area.

Gears and craft of Karwar: an overview

An account is given of the different types of gears and craft used to catch the pelagic and demersal fish in the inshore and estuary waters of Karwar, India. The main types of craft used during the fishing season September-May are: rampani boats, yendi boats, out-rigger boats, plank-built and dug-out canoes; important gears include: rampani, yendi, shore-seines, gill nets, boat seines, drift nets and hook and lines. Mechanized fishing, introduced during the sixties and seventies, included trawling and purse-seining. The types of gears used by the traditional fishermen depend on local conditions, seasons and distance covered from the shore. The major share to the total landings of fish in Karwar coast is brought mainly by the mechanized craft.

Study on fishing gears, species selectivity toward gears and catch composition of BSKB beel, Khulna, Bangladesh

An investigation on the types of fishing gear used and their species selectivity and effects on fishes of BSKB beel in Khulna was conducted from June '95 to January '96. Fishermen were found to follow 6 fishing techniques viz., netting, trapping, angling, spearing, dewatering and hand picking. Among them 23 types of the fishing gear was recorded to be used by the fishermen of which 7, 8, 4 and 4 are nets, traps, hooks and lines, and hand harpoon respectively. A total of 47 species of fish were identified in the catches of different gears used by the fishermen in BSKB beel. Particulars, mode of operation, fishing season and catch composition of different fishing gears were determined. Seine, cast and lift net, traps (charo, arinda and ghuni), and hooks and lines (dhawn and nol broshi) were recorded as nonselective gear considering the fish species caught. However, gill nets (punti, koi and fash jal), clasp nets (bhuti jal), some traps (khadom, tubo), hooks and lines (chip borshi, chasra) and all spears were used as more or less selective gear. With respect to species and its size fash jal, bhuti jal, trap (khadom, ramani), and koach, juti and jhupi among spears were regarded to be more or less large-species-gear. But punti jal, koi jal, trap (koi dughair, charo, tubo, arinda and ghuni), nol borshi and spear (ful-kuchi) were small-species-gear. Among all gears seine net, cast net, lift net, koi dughair and ramani were recorded deleterious for carps especially for stocked fingerlings. For relatively small sized wild fishes koi jal, punti jal and ghuni traps were identified as detrimental gear.

Investigations on the number of trials required for statistical comparison of fishing gears

The number of fishing trials required for comparing the efficiency of fishing gears was investigated. A unique solution to this problem did not appear to exist because of the heterogeneity of the experimental material. Sequential experimentation and analysis have been found to be a practical approach to this problem. By this, the experiment can be terminated almost after 35 days fishing for catches with standard error per unit as per cent of the mean about 30% or less (after logarithmic transformation). For data with mean catches less than 1.5 kg analysis of variance approach does not appear to be meaningful.

On the problem of nonadditivity in two-way analysis of variance of data for comparing the efficiency of fishing gears

To bring out the relative efficiency of various types of fishing gears, in the analysis of catch data, a combination of Tukey's test, consequent transformation and graphical analysis for outlier elimination has been introduced, which can be advantageously used for applying ANOVA techniques, Application of these procedures to actual sets of data showed that nonadditivity in the data was caused by either the presence of outliers, or the absence of a suitable transformation or both. As a corollary, the concurrent model: X sub(ij) = µ + α sub(i) + β sub(j) + λ α sub(i) β sub(j) + E sub(ij) adequately fits the data.

Fundamental study on the behavior of milkfish fry for the evaluation of the efficiency of traditional fry collecting gears in the Philippines

The response of Chanos chanos fry to moving and stationary nets of different mesh size and colour, underwater visibility of the nets and water filtration were studied. Results indicate that milkfish fry may be driven by nets of mesh size larger than that presently used; larger mesh size decreases the net resistance in the water so that collectors may move the equipment easily. The large mesh nets should be of a dark colour, preferably black for effective driving; bowever white mosquito net is best for the core end, since the fry are more easily visible on a white background.

A comparison between the catching efficiency of two milkfish fry collecting gears and their respective modifications

An experiment was conducted along the shore of Culasi, Antique in Panay to compare the milkfry (Chanos chanos) catching efficiency of the ordinary fry seine against its innovation and the ordinary sweeper against its 2 modifications. Results show that it is possible to replace the wings of the presently used sweeper and the ends of the fry seine with a coarse-meshed netting. This improvement decreases the water resistance of the gears and thus enables fry gatherers to use larger ones thereby giving more catch.

Environmental impact of wild shrimp seed collection with non-selective gears on coastal aquatic biodiversity

Collection of wild tiger shrimp (Penaeus monodon) seed with non-selective gears and its impact upon the coastal aquatic biodiversity has been investigated. Loss of undesired species as by-catch was estimated to be 1,075 individuals for collection of every desired shrimp seed which amounted to be 132 billion in a study area stretching 3 km long coastline of the Sagar Island under the Sunderban Biosphere, West Bengal, India. Non-penaeid shrimp seed and crab larvae accounted to be maximally destroyed as their overall contribution towards the by-catch were 56.5% and 29.44%, respectively. Though, rate of bycatch loss was found to be inversely correlated with the rate of shrimp seed collected per gear (r=-0.82, p<0.05) during the peak season (May-September), the overall relationship between them exhibited a linear relationship (r=0.73, p<0.05). By-catch loss for every shrimp seed collection tended to increase up to a daily collection of 2,500 numbers of shrimp seeds per gear followed by a decline. Coastal aquatic community was maximally damaged when the heterogeneity and stability as reflected by different diversity indices were higher.

Impacts of fishing gears, fishing methods and fishing effort in the fisheries of Lake Victoria and proposals for management

The initial subsistence fisheries of Lake Victoria were dominated by two indigenous tilapiines, Oreochromis esculentus (Graham 1929) and Oreochromis variabilis Boulenger 1906, exploited with simple fishing crafts and gears that had little impact on the fish stocks (Jackson 1971). Commercial fisheries, targeting the tilapia fishery, started at the beginning of the 20th Centurywhen cotton flax gillnets were first introduced in 1905 into the Nyanza Gulf in Kenya. Gillnets were quickly adopted around the whole lake and consequently, the native methods of fishing soon died out (Jackson 1971). Following the introduction of gillnets, fishing boats and their propulsion methods were also improved. These improvements in fishing capacity coincided with development of urban centres and increasing human population around the lake, which increased the demand for fishery products. To satisfy the increasing demand, fishing effort increased greatly during the 20th century, despite the decline of catch per unit of effort (CPUE) (Jackson 1971; Ogutu-Ohwayo 1990). The initial catch rates of 127mm (5 inch) mesh size gill nets in the tilapia-based fishery, in 1905, was in the range of 50 to 100 fish per gillnet of approximately 50 m in length. However, twenty years later, the catch rates of gillnets of the same mesh size had declined to about six fish per net and gillnets of smaller mesh sizes, which had better catch rates, had been introduced suggesting overfishing (Worthington and Worthington, 1933).

The impact of fishing gears and methods: with recommendations for management of the fisheries of Lakes Victoria, Kyoga and Nabugabo

Historical analysis has shown that use of destructive fishing gears and methods contributed much to the initial depletion of fish stocks from Lakes Victoria and Kyoga. From about 1930 to 1960, the fisheries of Lake Victoria were managed by controlling the mesh size of gill nets. Gill net s of less than 127 mm (5) stretched mesh had been prohibited on Lake Victoria because they cropped immature Oreochromis esculentus (Ngege) which were at that time the most important commercial species. When the mesh size restriction was repealed in the Ugandan, Tanzanian and Kenya, there was a shift to smaller meshes which cropped immature tilapia and other large species and led to a collapse in the fishery.

The Nile perch fishery: traditional and emerging fisheries, overfishing and the use of illegal gears on Lake Albert

The fisheries of Lake Albert have come under increasing focus due to several driving forces that have synergistically evolved resulting into concerns from diverse stakeholders. The driving forces include: the commercialization of the fisheries with entry into the value chain of industrial fish processing, a decline in fish stocks especially of the large-size fishes and the emergency of the light - fishing targeting small pelagic fishes. In addition, the assumption by some opinion leaders that light-fishing (use of light) has destroyed the Nile perch fishery of Lake Albert, other factors such as cross-border fishing conflicts, the emergence of oil, an influx of traders in fish-related activities, and the limited regulatory and enforcement regimes for the diverse commercially exploited fish fauna of Lake Albert all require continuous information and action.