Publication Date:
2021-07-12
Description:
Pooled one-year (January to December, 1999) length-frequency data of fish speciessampled from catches of five randomly selected artisanal fishers, using unmotorized dug-out canoe were fed into FISAT (FAO-ICLARM Stock Assessment Tool) to evaluate mortality coefficients. The resultant natural mortality coefficients of the11 commercially important fish species showed that Sarotherodon melanotheron (2.24y ('), Galeoides decadactylus (1.96y(1), Eucinostomus melanopterus (1.58 y(,), Tilapia guineensis (1.44 y('), Pseudotolithus elongatus (1.22 y(,) and Ilisha africana (1.08 y(1) had the highest natural mortality rates and indicative of fast growth (i.e. rapidly approaching asymptotic length (Loo); the reverse being true for Chrysichthys nigrodigitatus (0.66 y(1); Pomadasys jubelini (0.74 y('); Ethmalosa fimbriata (0.78 vr'). Lutjanus goreensis and Uzagrandisquamis (0.87 yr'). The generally high total mortality values of 0.88 y(1 for C. nigrodigitatusto3.83 y(' (P. elongatus) points to death due not only to legal fishing activities but also great impacts from illegal and obnoxious fishing practices, pollution, environmental degradation, and the consequent need for management of the fishery resource within the Niger Delta of Nigeria. Management measures such as enforced licensing and registration of fishers and fishing craft, establishment of marine reserve areas and fishing registration centers would enhance sustainable use of the economically viable fishery resources within the coastal states of Nigeria and West Africa at large. Pooled one-year (January to December, 1999) length-frequency data of fish speciessampled from catches of five randomly selected artisanal fishers, using unmotorized dug-out canoe were fed into FISAT (FAO-ICLARM Stock Assessment Tool) to evaluate mortality coefficients. The resultant natural mortality coefficients of the11 commercially important fish species showed that Sarotherodon melanotheron (2.24y ('), Galeoides decadactylus (1.96y(1), Eucinostomus melanopterus (1.58 y(,), Tilapia guineensis (1.44 y('), Pseudotolithus elongatus (1.22 y(,) and Ilisha africana (1.08 y(1) had the highest natural mortality rates and indicative of fast growth (i.e. rapidly approaching asymptotic length (Loo); the reverse being true for Chrysichthys nigrodigitatus (0.66 y(1); Pomadasys jubelini (0.74 y('); Ethmalosa fimbriata (0.78 vr'). Lutjanus goreensis and Uzagrandisquamis (0.87 yr'). The generally high total mortality values of 0.88 y(1 for C. nigrodigitatusto3.83 y(' (P. elongatus) points to death due not only to legal fishing activities but also great impacts from illegal and obnoxious fishing practices, pollution, environmental degradation, and the consequent need for management of the fishery resource within the Niger Delta of Nigeria. Management measures such as enforced licensing and registration of fishers and fishing craft, establishment of marine reserve areas and fishing registration centers would enhance sustainable use of the economically viable fishery resources within the coastal states of Nigeria and West Africa at large.
Keywords:
Fisheries
;
Management
Repository Name:
AquaDocs
Type:
conference_item
,
TRUE
Format:
application/pdf
Format:
application/pdf
Format:
95-99
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