Journal of Tropical Ecology



Effects of Cyclone Waka on flying foxes (Pteropus tonganus) in the Vava'u Islands of Tonga


Kim R. McConkey a1c1p1, Donald R. Drake a2, Janet Franklin a3 and Filipe Tonga a4
a1 Wildlife Research Group, Department of Anatomy, Cambridge University, Cambridge CB2 3DY, UK
a2 Botany Department, University of Hawaii at Manoa, 3190 Maile Way, Honolulu, HI 96822, USA
a3 Department of Biology, San Diego State University, San Diego CA 92182-4614, USA
a4 IFAW and Whales Alive, Box 17, Neiafu, Tonga

Article author query
mcconkey kr   [PubMed][Google Scholar] 
drake dr   [PubMed][Google Scholar] 
franklin j   [PubMed][Google Scholar] 
tonga f   [PubMed][Google Scholar] 

Abstract

Severe tropical cyclones are a major cause of episodic mortality for Pacific Island flying foxes (large fruit bats). Many flying foxes starve after forests are stripped of food sources, and hunting by humans may also increase in the post-cyclone period. In December 2001, Cyclone Waka passed directly over the Vava'u Islands in the Kingdom of Tonga, western Polynesia. We visited the islands 6 mo later to survey the flying fox (Pteropus tonganus) population and assess availability of potential food items (fruit and flower) in primary, secondary and plantation forests. Less than 20% of the pre-cyclone bat population (surveyed in 1999–2001) remained 6 mo after the storm. The density of potential food trees in flower or fruit at this time was only 15% of pre-cyclone density, and the main species available were different in the two time periods. The highest density of potential food trees occurred in secondary forest (26 flowering or fruiting trees ha−1) and plantations (23 ha−1); primary forest offered the least food (18 ha−1). Since 65–70% of the land area has been converted to agricultural plantations, this vegetation type had the highest absolute number of food-bearing trees – almost seven times that of primary forest. Flowering coconuts (Cocos nucifera) were the most abundant food source overall and we suggest that this species may be important in sustaining flying foxes following severe storms.

(Accepted December 22 2003)


Key Words: Cyclone Waka; disturbance; flying fox; frugivory; Pteropus tonganus; Polynesia; Tonga.

Correspondence:
c1 Corresponding author.
p1 Current address: AVRA House, 7-102/54 Sai Enclave, Habshiguda, Hyderabad 500007, India. Email: kimm@sancharnet.in