Many mammals use multimodal sensory information to find their food in complex environments. We studied the roles of olfactory and visual cues in the foraging behaviour of Rousettus leschenaulti, a tongue-clicking megachiropteran bat. We conducted experiments by offering a whole fruit, mashed fruit without shape and an artificial fruit to R. leschenaulti in dim light as well as in total darkness. R. leschenaulti responded to whole guava fruit and mashed guava fruit even in total darkness, whereas, artificial fruit similar to real fruit in size, shape and structure was ignored even when illuminated. These results reveal that odour may act as the primary cue for R. leschenaulti in finding fruit.

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The short-nosed fruit bat Cynopterus sphinx is known to exhibit resource defence polygyny as its primary mating strategy. Tent construction by harem males to recruit females represents a heavy investment of time and effort, which is not done by nonharem males. The previously unobserved mode of harem formation by the solitary males was studied using mark-recapture and radio-telemetry. In our observation, the solitary males roosting near to harems started recruiting females by occupying the tent abandoned by the harems. This result suggests that the transition of nonharem male to harem male status possibly by a previously unobserved mode and the female recruitment is associated with resource (roost). It implies that the solitary males are actively involving in female recruitment and also presumably mating.

We used radiotelemetry to evaluate relationships between female Cynopterus sphinx and their young during the late lactation and weaning periods. Our observations suggest that young C. sphinx may be tutored by their mothers during this period. Before young are weaned, females intermittently visit their young during nightly feeding bouts. During the weaning period, mothers forage near their day roosts and are accompanied by or forage near their young. We suggest that observational learning during the late lactation and weaning period occurs when young C. sphinx accompany their mothers on foraging flights. Thus, young bats may have an opportunity to learn the location of profitable food patches.

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