Bat foraging strategies and pollination of Madhuca latifolia (Sapotaceae) in southern India

Abstract

The sympatrically occurring Indian short-nosed fruit bat Cynopterus sphinx and Indian flying fox Pteropus giganteus visit Madhuca latifolia (Sapotaceae), which offers fleshy corollas (≈ 300 mg) to pollinating bats. The flowers are white, tiny and in dense fascicles. The foraging activities of the two bat species were segregated in space and time. Cynopterus sphinx fed on resources at lower heights in the trees than P. giganteus and its peak foraging activity occurred at 19:30 h, before that of P. giganteus. Foraging activities involved short searching flights followed by landing and removal of the corolla by mouth. Cynopterus sphinx detached single corollas from fascicles and carried them to nearby feeding roosts, where it sucked the juice and spat out the fibrous remains. Pteropus giganteus landed on top of the trees and fed on the corollas in situ; its peak activity occurred at 20:30 h. This species glided and crawled between the branches and held the branches with claws and forearms when removing fleshy corollas with its mouth. Both C. sphinx and P. giganteus consumed fleshy corollas with attached stamens and left the gynoecium intact. Bagging experiments showed that fruit-set in bat-visited flowers was significantly higher (P < 0.001) than in self-pollinated flowers.