Foraging strategies of generalist and specialist Old World nectar bats in response to temporally variable floral resources

Foraging theory predicts that generalist foragers should switch resources more readily, while specialist foragers should remain constant to preferred food resources. Plant-pollinator interactions provide a convenient system to test such predictions because floral resources are often temporally patchy, thus requiring long-lived pollinators to switch resources seasonally. Furthermore, flowering phenologies range from ‘steady-state’ (low-rewarding but highly reliable) to ‘big-bang’ (high-rewarding but ephemeral) plant species. We assessed how nectarivorous Old World bats respond to this temporally variable floral environment by examining their diets throughout the year. Over 15 months of fieldwork in southern Thailand, we simultaneously: (1) recorded the flowering phenologies of six bat-pollinated plant taxa; and (2) assessed the diets of seven common flower-visiting bat species. As predicted, the generalist nectarivore (Eonycteris spelaea) frequently switched diets and utilized both big-b...