Reproductive strategy of Oreochromis niloticus (Pisces: Cichlidae) in Opa reservoir, Ile-Ife, Nigeria

The fish family Cichlidae has a large diversity and dominates African freshwater bodies, with over 200 species reported in inland waters. Sampling for the fish Oreochromis niloticus (Linnaeus) in Opa reservoir, Nigeria, started in October 1997 and extended until February 2000. The fishing methods em...

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Detalles Bibliográficos
Autores: Komolafe, O.O., Arawomo, G.A.O.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Costa Rica
Institución:Universidad de Costa Rica
Repositorio:Portal de Revistas UCR
Idioma:inglés
OAI Identifier:oai:portal.ucr.ac.cr:article/6034
Acceso en línea:https://revistas.ucr.ac.cr/index.php/rbt/article/view/6034
Access Level:acceso abierto
Palabra clave:Época de reproducción
hábitos de reproducción
proporción de sexos
índice gonadosomático
tilapia
fecundidad
Oreochromis niloticus.
Breeding season
breeding habits
sex ratio
gonadosomatic index
fecundity
Oreochromis niloticus
Descripción
Sumario:The fish family Cichlidae has a large diversity and dominates African freshwater bodies, with over 200 species reported in inland waters. Sampling for the fish Oreochromis niloticus (Linnaeus) in Opa reservoir, Nigeria, started in October 1997 and extended until February 2000. The fishing methods employed for collecting the 1 430 specimens were cast netting and gillnetting. Egg diameter varied between 2.12 mm and 2.69 mm with a mean of 2.47±0.02. Female gonadosomatic index was 1.34±0.01 (0.12-4.06, n= 637). The male gonadosomatic index was 0.39±0.02 (0.03-1.67, n= 789). In Opa reservoir, O. niloticus bred throughout the study period. The species was a maternal mouth brooder with the female fish carrying eggs and fry in the buccal cavities. The sex ratio of O. niloticus was approximately 1:1 in the reservoir. The fecundity of the species was between 73 eggs and 1 810 eggs per female with a mean fecundity of 815 eggs.