Feedingbehaviour of the dawn bat (Eonycteris spelaea) promotes cross pollination of economically important plants in Southeast Asia

Abstract

Eonycteris spelaea is recognized as the principal pollinator of most chiropterophilous plants in SE Asia. The present study describes its feeding behaviour and clarifies its role in cross pollinating these highly self-incompatible plants. Ten individuals of E. spelaea were radio-tracked during the flowering period of durian (Durio zibethinus) and petai (Parkia speciosa) in an agricultural mosaic in southern Thailand. Eonycteris spelaea makes a mean of seven visits per hour to these trees and 80-86% of each feeding bout involves visits to multiple conspecific trees. During each visit, 93% of D. zibethinus stigmas and 50% of P. speciosa stigmas were loaded with conspecific pollen. Eonycteris spelaea was the most common bat visitor to the trees. High visitation frequency and conspecific pollen deposition by E. spelaea to D. zibethinus and P. speciosa indicates that this nectarivorous bat is an effective pollinator. Mixed planting of chiropterophilous trees in fruit orchards is recommended to ensure regular visits of E. spelaea. Protecting natural roost caves of E. spelaea is also essential in order to maintain the vital ecosystem service provided by these bats.