Trophic ecology of neonates and juveniles of the silky shark, Carcharhinus falciformis, off the coast of Guerrero, Mexico

The silky shark, Carcharhinus falciformis, is one of the most important shark species in the small-scale fishery landings on the Pacific coast of Mexico. In the present work, we report the main food components of C. falciformis caught by small-scale fisheries in Acapulco, Guerrero, Mexico, according...

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Detalles Bibliográficos
Autores: Sandoval-Ramírez, Adriana, Moreno-Díaz, Giovanni, Rojas-Herrera, Agustín A, Violante-González, Juan, Loyo-De la Paz, Lui J, Cerdenares-Ladrón de Guevara, Genoveva
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:México
Institución:UNIVERSIDAD AUTÓNOMA DE BAJA CALIFORNIA
Repositorio:Ciencias Marinas
Idioma:inglés
español
OAI Identifier:oai:cienciasmarinas.com.mx:article/3201
Acceso en línea:https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/3201
Access Level:acceso abierto
Palabra clave:Carcharhinus falciformis
feeding strategy
juveniles
neonates
trophic level
estrategia de alimentación
neonatos
nivel trófico
Descripción
Sumario:The silky shark, Carcharhinus falciformis, is one of the most important shark species in the small-scale fishery landings on the Pacific coast of Mexico. In the present work, we report the main food components of C. falciformis caught by small-scale fisheries in Acapulco, Guerrero, Mexico, according to size (neonates and juveniles) and sex (males and females), as well as reporting the niche breadth and trophic level. A total of 165 stomachs of C. falciformis were collected, of which 57 contained food and 108 were empty. A total of 11 prey groups were identified: 4 crustaceans, 3 fish, 2 cephalopods, 1 sea turtle, and 1 bird. According to the prey-specific index of relative importance (%PSIRI), crustaceans accounted for 77.17% of the diet. The crab Portunus xantusii was the most important component of the diet of neonates, juveniles, males, and females. The diets did not show great differences between neonates and juveniles and between males and females (Morisita–Horn index: 0.86 and 0.80, respectively). The silky shark presented a narrow niche breadth in all categories, indicating a specialist-type feeding strategy (Levin’s index <0.60). According to Amundsen’s model, C. falciformis showed preference for P. xantusii. The trophic level determined for C. falciformis indicated that it is a secondary predator.