Gear considerations in the artisanal shrimp fishery of the Cross River Estuary, Nigeria

The artisanal shrimp fishery of the Cross River Estuary, SE Nigeria is exploited with three main shrimping gears, viz: beach seine, push net and trap. While the beach seine and push net are active gears, the trap is passive. Catch composition from the three gears was analysed for species diversity, catch contribution in weight and sex ratio. The trap showed the lowest species diversity, with only three Macrobrachium (M. macrobrachion, M. vollenhovenii and M. equidens) species represented in the catch, while Callinectes crab and Eleotris were by-catch. The complete absence of Penaeus notialis from trap catches throughout the sampling period of eighteen months was remarkable, while M. equidens was very low in abundance. The beach seine and push net had similar species composition in their catches with more than thirteen shrimp species represented. The catch per unit effort for the three gears varied, with beach seine contributing 46.13%, push net 24.41 % and trap 29.46%, of the overall catch. The sex ratio (male: female) was 1 :2.2 (beach seine), 1 :2.1 (push net), 1:2.15 (trap) for M. macrobrachion, 1 :1.27 (beach seine), 1 :1.32 (push net) and 1 :1.64 (trap), for M. vollenhovenii. The size structure showed more juveniles (below 40 mm) in beach seine and push net. Analysis of catches from the three gears showed some complexities as active and passive gears manifested extreme characteristics in their selection. In managing this fishery, therefore, a middle-of-the road option would be necessary, and we recommend the closed season.

Enregistré dans:
Détails bibliographiques
Auteurs principaux: Nwosu, F.M., Holzlohner, S.
Format: conference_item biblioteca
Langue:English
Publié: Fisheries Society of Nigeria 2007
Sujets:Fisheries, Nigeria, Cross River Estuary, brackishwater environment, Gear selectivity, Gear research, Catch statistics, Shrimp fisheries, Catch composition, Stock assessment, By catch,
Accès en ligne:http://hdl.handle.net/1834/37737
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!