An Experimental Analysis of the Food Location Behavior of Frugivorous Bats

(Uploaded by Plazi for the Bat Literature Project) Models of optimal foraging often separate the time and energy expended in getting to a feeding area (commuting costs) from the time and energy expended in searching for food (search costs) in animals that are "pure searchers." We predict that under certain circumstances (e.g., a relatively uniform resource distribution) searching and commuting behavior will be synchronous, whereas under other circumstances (e.g., a relatively patchy resource distribution) these two behaviors will be temporally separated. We have tested these predictions by studying the foraging and food location behavior of several species of Costa Rican frugivorous bats using mist-netting programs, radiotelemetry, and fruit relocation experiments. Concurrent observations were made on the phenology and distribution patterns of the six fruit species used in the relocation experiments. The mist-netting program allowed us to determine the food habits of the common frugivorous bats in our study area and to identify the major chiropteran dispersal agents of the six fruit species. The radio-tracking program provided detailed information on the foraging behavior of one of the most important seed dispersal agents, Carollia perspicillata, whose individuals commute up to 2.7 km from a central day roost before beginning to feed.