Popis: |
FORAGING patterns may vary within and among species, and in response to changes in the food resource. Schoener (1971) suggested that 4 factors influence foraging: diet, time, space and group size. Zaret and Rand (1971) have shown that when food abundance is low, the overlap in diet among sympatric fish species is low; and that when food abundance is high the overlap in diet is also high. Similarly, Orians and Horn (1969) found a high degree of overlap in both diet and habitat among closelyrelated bird species when food was abundant. However, Schoener (1968) found that in Anolis lizards when habitat overlaps were high there were distinct differences in diet, and when diets were similar the species differed in habitat utilization. The purpose of this study is to examine the relationships between diet, habitat specialization and species abundances under changes in food abundance. |