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Continental J. Fisheries and Aquatic Science 3: 37 - 41, 2009
© Wilolud Online Journals, 2009.
EFFECT OF BAITS TYPE ON FISH CONGREGATION AND CATCH EFFICIENCY OF CASTNET IN LAKE
KAINJI, NIGERIA.
Y.B. Ahmed
1
, L.A. Argungu
2
and T.A. Tagago
3
1
Federal College Of Freshwater Fisheries Technology,P.M.B. 1500, New Bussa, Niger State.
2
Department of
Forestry and Fisheries,Usmanu Danfodiyo University,P.M. 2346, Sokoto, Nigeria.
3
Kebbi Agricultural and Rural
Development Authority,Birnin Kebbi, Kebbi State.
ABSTRACT
The effect of baits, rice bran (Oryza sativa L.) and corn bran (Zea mays L.) on fish aggregation
and catch efficiency of castnet in Lake Kainji was conducted. 25.4mm stretched mesh size
multifilament (PA) nylon net was used for the construction of castnet. The experiment was
Complete Randomized Design (CRD) with three replications for nineteen consecutive fishing
days. Three treatments were employed; castnetting after baiting with rice bran, with corn-bran,
and castneting without bait (control). Thirteen fish species were caught from eight families.
The number of fish caught was 336, of which 48.5 and 27.1% were castnetting with corn bran
and without bait while castnetting with rice bran recorded the least (24.4%). The biomass of
fish caught was 4627.7g (4.6kg) of which the highest percentages 51.4 and 28.6% followed
same trend as that of number of fish caught. Comparison of the overall number and biomass of
fish capture indicated that Tilapia zilli ranked highest, next by Citharinus citharus and
Hydrocynus forskalii. Recommendations have been made for areas of further studies in these
aspects.
INTRODUCTION
Castnet fishing is regarded as a traditional method of catching fish that has been used since antiquity. The most
widely used artisanal fishing gears in Nigerian freshwater and brackish water as well as coastal waters, are gillnets
and castnets (FAO, 1969). Castnet are conical falling nets with lead (Pb) weights attached at regular intervals along
the perimeter of the cone (Udolisa and Solarin, 1979). It is an active fishing gear; that is it catches fish instantly.
Hayes et al. (1996) reported that a light or bait is often used to attract the target fish into an area within the castnet’s
range. Fishing baits lures and attraction devices, are often incorporated into some fishing gears in order to improve
their efficiency such fishing gears include handlines, longlines, trolling and traps etc (Ahmed et al, 2005). Baits
may include rotten meat, dead or live fish, palm nuts or corn bran depending on the feeding and behavioral
characteristics of the target fish species.
The castnet fishery is probably the next most damaging fishing method to juvenile fish after beach seines (du Feu
and Abiodun, 1999). It caught 34% of the total tilapines, 24% Citharinus and 19% of all Labeo, at a mean size upto
50% less than gillnets in the case of Citharinus. This study therefore intends to assess the effects of two baits rice
bran (Oryza sativa L.) and corn bran (Zea mays L.) and, without baits on the efficiency of castnet in Lake Kainji.
MATERIALS AND METHODS
The experiment was conducted in the lower basin of Lake Kainji about 6.5 km away from the Federal College of
Freshwater Fisheries Technology, New Bussa, Niger State, between July and August, 2008. The description of
study area is adequately made in Ahmed et al, (2006).
The castnet construction was followed by the same method that was used by Udolisa et al. (1994) and Udolisa and
Solarin (1979). Two types of baits were used corn bran and rice bran, and casneting without bait was used as
control. A net was cast, a waiting period of five minutes was observed to allow the weight to settle to the bottom of
the sampling areas. The net was pulled with both hands to retrieve it. The experiment was Complete Randomized
Design (CRD) with three replications for nineteen consecutive fishing days. The fish caught were packed in
separate labelled container for each treatment.