Feeding Behaviour and Foraging Strategies of Captive Phyllostomid Fruit Bats: An Experimental Study

Abstract

SUMMARY (1) Feeding rhythms, rates, and fruit selectivity were observed in flight cage experiments involving seven species of frugivorous bats (Chiroptera: Phyllostomidae) from two distinct foraging guilds: canopy frugivores specializing on superabundant fruits of canopy trees and groundstorey frugivores specializing on fruits of shrubs and understorey trees of low fecundity. (2) Bat species differed in handling times of individual fruits, feeding rhythms, and fruit species selectivity with groups of bat species corresponding to previously defined guilds. Canopy frugivores fed continuously throughout most of the night and ate each fruit slowly. Groundstorey frugivores fed in a series of discontinuous bouts separated by periods of roosting/sleeping and ate individual fruits rapidly. (3) Bat species differed in cumulative food item feeding rates over 2-4 h experimental periods, but species subsets did not correspond to established guilds. (4) Paired fruit choice tests showed that captive bats selected fruits that wild populations of their species commonly eat. Groundstorey frugivores selected fruits high in nutrient content. Canopy frugivores selected familiar fruits of low nutrient content over nutritionally higher quality fruits that wild conspecifics rarely eat. (5) Exploitation competition for some limited food resources is discussed as a possible mechanism that has led to resource partitioning and foraging specialization in neotropical