Poster presentation 12th International Mammalogical Congress

Chinese fan palms as important food source for the Daito flying-fox (Pteropus dasymallus daitoensis) on Daito Islands, Japan (#728)

Keiichiro Abe 1 , Haruka Abe 1 , Shun Kobayashi 1 , Tetsuo Denda 1 , Masako Izawa 1
  1. University of the Ryukyus, Nishihara, OKINAWA, Japan

The Daito flying-fox Pteropus dasymallus daitoensis is a subspecies of the Ryukyu flying-fox, endemic to Daito Islands in the Ryukyu Archipelago, Japan. The Chinese fan palm Livistona chinensis dominates the natural forests of the oceanic Daito Islands, and plays an important role in the ecosystem of these islands. Daito flying-foxes feed on inflorescences of this palm. In this study, we aimed to investigate the importance of Chinese fan palms as food source for Daito flying-foxes. The flowering/fruiting phenology of this palm and other food plants, and the feeding behaviors of flying-foxes were investigated in 2013, 2015, and 2016. In 2013, the feeding frequency of flying-foxes increased with increasing number of flowering palms; however, it remained low in 2015 and 2016. The fruiting periods of Calophyllum inophyllum and Terminalia catappa, two major food plants for flying-foxes, overlapped with most of the flowering period of the Chinese fan palms; flying-foxes fed on these fruits. As these species are abundantly planted as windbreak and garden trees, flying-foxes can normally utilize these plants more frequently during the flowering period of the Chinese fan palms. In 2013, many flowers and fruits on the islands dropped or withered because of two strong typhoons. The flowers could recover from the damage more quickly than fruits, which might explain the increased feeding frequency of flying-foxes observed that year. These findings suggest that the Chinese fan palms are an important food source for the Daito flying-foxes, to compensate for the food shortage caused by typhoons.