Solitary and Group Foraging: Two Flower-Visiting Patterns of the Lesser Spear-Nosed Bat Phyllostomus discolor

Abstract

Solitary and group-foraging patterns were observed in the lesser spear-nosed bat, Phyllostomus discolor, while visiting flowers. Observations made at flowering plants of Lafoensia glyptocarpa and two species of Bauhinia in southeastern Brazil suggest that these patterns may be related to the number of flowers or amount of food presented by a given plant. LESSER SPEAR-NOSED BATS, Phyllostomus discolor, are known to forage in groups while feeding on flowers or fruits (Carvalho 1960, Vogel 1968, Heithaus et al. 1974, 1975). Group foraging in P. discolor while visiting flowers of Parkia gigantocarpa in northern Brazil was reported by Carvalho (1960); Vogel (1968) made similar observations with this bat species on Parkia auriculata and Hymenaea courbaril in the same region. Flocking in the lesser spearnosed bat while visiting flowers of Bauhinia pauletia was observed by Heithaus et al. (1974) in Costa Rica. The above-mentioned plants offer a relatively large number of flowers, and total amount of nectar, during the flowering season. Netting results obtained by Heithaus et al. (1975) in Costa Rica suggest that group foraging may be the usual feeding behavior of P. discolor. During our studies on bat pollination in southeastern Brazil we have observed that Phyllostomus d. discolor visits flowers singly as well as in groups. In this paper we describe visitation patterns of P. discolor to three plant species, Lafoensia glyptocarpa and two species of Bauhinia.