COMPARATIVE EVALUATION OF THE EFFICIENCY OF TRADITIONAL AND MODIFIED MALIAN TRAPS IN CAPTURE FISHERIES

Abstract

An evaluation to comparatively determine the efficiency of a modified and traditional Malian traps in capture fisheries was carried out in Dan-Zaria Dam,Niger State.The traps were designed and constructed with the following wooden frame dimensions:- the traditional trap which was cone shaped, had a base diameter of 135cm, middle diameter of 115cm and terminal diameter of 77cm and height of 75cm; while that of the modified trap which was rectangular-shaped, had a base length of 100cm, width of 50cm and height of 40cm both were enclosed in a netting materials of 3.75cm mesh size. The traditional traps had two non-return valve while the modified had three nonreturn valves with recovery opening at top of each. They were both designed and constructed simultaneously at site. The traps were both introduced into the water and set unbaited in pairs at three different location in the Dam. To aid both stability and permanence, stone weights and wet grass were placed on top of the traps and stick pegged closed to them for easy identification during monitoring visits. Collection of catch was carried out twice weekly for a period of six weeks. At each visit, the location of traps were alter to create wider sampling area. The catches were each brought into the laboratory for analysis. A total of twelve visits were made and analysis of catches showed that a total of 146 fishes and turtles were caught by both traps. The comparative catches analysis of the total showed that traditional Malian trap caught 82 fishes only, comprising of 45 Clarias gariepinus, 25 Clarias anguillaries and 12 Oreochromis niloticus representing 54.87%, 30.48%, and 14.63% respecttively; While the modified traps caught 50 fishes, comprising 28 Clarias gariepinus, 15 Clarias anguillaris and 7 Oreochromis niloticus representing 43.73%, 23.43% and 10.93% respectively and 14 turtles (Testudinidae). The species diversity index for the traditional and modified Malian traps were 0.023 and 0.027 respectively. Based on the results, it was concluded that while the traditional traps had higher catched than modified traps there was no significant difference (P>0.05) between the two, hence in terms of catch efficiency the traditional trap is more eficient than the modified trap,however, modified trap had the advantage of trapping other aquatic living resources(Turtles) than fish.