Size, sex and seasonal dynamics in the dietary composition of Brycinus nurse (Pisces: Characidae), from Asa reservoir, Ilorin, Nigeria

Specimens of the characid Brycinus nurse (N = 980) were collected in Asa reservoir, Nigeria, from November 1991 to October 1993. The diet was analyzed from stomach contents using the frequency of occurrence, numerical and gravimetric methods. Fish sex affected occurrence, number and weight of food i...

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Detalhes bibliográficos
Autor: Saliu, J K
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:Costa Rica
Recursos:Universidad de Costa Rica
Repositorio:Portal de Revistas UCR
Idioma:inglés
OAI Identifier:oai:portal.ucr.ac.cr:article/16255
Acesso em linha:https://revistas.ucr.ac.cr/index.php/rbt/article/view/16255
Access Level:acceso abierto
Palavra-chave:brycinus nurse
characidae
dietary composition
nigeria
Descrição
Resumo:Specimens of the characid Brycinus nurse (N = 980) were collected in Asa reservoir, Nigeria, from November 1991 to October 1993. The diet was analyzed from stomach contents using the frequency of occurrence, numerical and gravimetric methods. Fish sex affected occurrence, number and weight of food items. The relative importance index (RI) indicates that diet varied seasonally. There was also a noticeable switch from insectivorous habits in small fish (less than 18 cm) to herbivorous feeding habits in larger fish. The ability of the fish to evolve trophic strategies that ensure optimum foraging despite seasonal changes can account for its success in the lake.