P-48
Prey Selectivity and Trophic Strategies in a Coastal Soft Bottom Fish Assemblage in Central Mexican Pacific
Flores-Ortega, JR., Godínez-Domínguez, E., González-Sansón, G.
The relationships between food availability and prey selectivity in species of a soft bottom fish assemblage of the central Mexican Pacific were surveyed. The main food categories in the diet of sixteen predator fish species living on shallow soft bottoms were shrimps, crabs and small-sized fish. The most abundant potential food groups in the environment were peracarids, polychaetes, shrimps, molluscs and crabs. Only six species (D. holocantus, P. ruscarius, S. russula, U. munda, U. halleri y U. rogersi) showed active selectivity (Ivlev's index>0.75(>0.75) in at least one prey category. Shrimps were the most positively preferred prey group. Seasonal changes in prey communities related to environment dynamics, generalist feeding habits of predators and low prey selectivity, could be components of a strategy for avoiding resource competition in a high diversity coastal ecosystem.