Rocky-reef fish assemblages at San José Island, Mexico

We analyzed the composition, diversity, and abundance of marine fish at rocky reefs off San José island, Mexico between October 2001 and August 2002. Fish species were recorded using a visual census in 5 sampling areas of 50 by 5 meters at 2 depths, shallow (1-3 meters) and intermediate (5-7 meters)...

Descripción completa

Detalles Bibliográficos
Autores: Carmen Amelia Villegas-Sánchez, Leonardo Andrés Abitia-Cárdenas, Francisco Javier Gutiérrez-Sánchez, Felipe Galván-Magaña
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:México
Institución:Instituto Politécnico Nacional
Repositorio:Redalyc-IPN
OAI Identifier:oai:redalyc.org:42511957019
Acceso en línea:https://www.redalyc.org/articulo.oa?id=42511957019
Access Level:acceso abierto
Palabra clave:Biología
rocky reef
Fish diversity
Gulf of California
Baja California Sur
Descripción
Sumario:We analyzed the composition, diversity, and abundance of marine fish at rocky reefs off San José island, Mexico between October 2001 and August 2002. Fish species were recorded using a visual census in 5 sampling areas of 50 by 5 meters at 2 depths, shallow (1-3 meters) and intermediate (5-7 meters). A total of 26 946 organisms were counted, belonging to 84 species. The families Serranidae (9 species), Labridae (8), Pomacentridae (7), and Haemulidae (6) were the most representative. We measured the rugosity of the bottom surface, which showed a positive relationship with abundance, richness, and fi sh diversity. The ocean bottom off San José island is covered with various size rocks that offer more feeding and refuge areas to fsh assemblages than other areas. The ecological index increased during the warm season. Diversity and richness showed signifi cant variations (P<0.05) by depth, with the highest values in exposed locations around the island (Conejo, Pardito, and San Francisquito). The biological value index indicated that the most representative fi sh species were Stegastes rectifraenum, Abudefduf troschelii, Thalassoma lucasanum, Scarus ghobban, and Mulloidichthys dentatus. The depth and wave exposure were the 2 environmental variables with the most influence on the structure of rocky-reef fish assemblages.