Please use this identifier to cite or link to this item:
Population Size and Natural History of Mariana Fruit Bats (Chiroptera: Pteropodidae) on Sarigan, Mariana Islands
|Title:||Population Size and Natural History of Mariana Fruit Bats (Chiroptera: Pteropodidae) on Sarigan, Mariana Islands|
|Authors:||Wiles, Gary J.|
Johnson, Nathan C.
|Issue Date:||Oct 2004|
|Publisher:||University of Hawai'i Press|
|Citation:||Wiles GJ, Johnson NC. 2004. Population size and natural history of Mariana fruit bats (Chiroptera: Pteropodidae) on Sarigan, Mariana Islands. Pac Sci 58(4): 585-596.|
|Abstract:||Based on count results, we estimated the population of Mariana fruit
bats (Pteropus mariannus Desmarest) on Sarigan, Mariana Islands, to number
150-200 bats in 1999, 185-235 bats in 2000, and about 300-400 bats in 2001.
Our results, plus those of two previous surveys, indicate that bat abundance on
the island probably remained relatively stable at about 125-235 animals during
much of the period from 1983 to 2000, then increased suddenly in 2001, most
likely due to immigration from a neighboring island. Sarigan's population differs
from those of larger islands in the archipelago by usually having smaller roost
sizes, typically 3-75 bats, and large numbers of solitary bats that at times comprise
up to half of the population. Colonies and smaller aggregations were
composed primarily of harems with multiple females, whereas a nearly equal sex
ratio occurred among solitary animals. Colonies roosted in isolated coconut
trees in open grasslands and in native forest stands of various sizes, but avoided
dense coconut forest. An estimated 30-50% of harem and solitary females possessed
young in July 1999. Bats were recorded feeding on just six species of
plants, which partly reflects the island's impoverished flora. We speculate that
fruit bat abundance on Sarigan is limited primarily by food availability rather
than hunting losses, in contrast to some other islands in the Marianas. Our study
supports the contention that populations of P. mariannus in the northern Marianas
are usually sedentary, but that interisland movements of larger numbers
of bats may occur rarely.
|Appears in Collections:||Pacific Science Volume 58, Number 4, 2004|
Items in ScholarSpace are protected by copyright, with all rights reserved, unless otherwise indicated.