Comparison of fruit syndromes between the Egyptian fruit-bat (Rousettus aegyptiacus) and birds in East Mediterranean habitats

This study analyses the fruit syndrome of the Egyptian fruit-bat, Rousettus aegyptiacus, the only fruit-bat found in East Mediterranean habitats. Two different sets of bat-fruit syndromes were revealed. One follows the general bat-fruit syndrome and one represents a special case of bat-dispersed fruit syndrome only found in East Mediterranean habitats. The latter syndrome is characterized by dry fruits with a relatively high protein content. Fruit species that belong to this syndrome are available mostly in winter (when the fruit-bat faces a severe shortage in fruit availability and inadequate fruit quality). The fruit syndromes and dietary overlap between frugivorous birds (based on the literature) and the fruit-bat were also studied. Features associated with each set of fruit species generally follow the known bat and bird syndromes. Bird-dispersed fruits tend to be small, with a high seed mass to pulp mass, variable in fat content and characterized by a high ash content. However, when the shared fruit species were included in the analysis, no significant differences were found in fruit features between the bird-dispersed and bat-dispersed fruit syndromes. A limited and asymmetrical dietary overlap was observed between these two taxa, mainly between introduced and cultivated fruits.