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Vol. 38 No. 4, 1999
Is There Current Competition between Sympatric Siberian
Weasels (Mustela sibirica) and
Ferret Badgers (Melogale moschata)
in a Subtropical Forest Ecosystem of Taiwan?
Hai-Yin
Wu*
Institute
of Zoology, Academia Sinica, Taipei, Taiwan 115
Hai-Yin
Wu (1999) The Siberian weasels (Mustela sibirica) and ferret
badgers (Melogale moschata)
sympatric in the Guandaushi Forest are of particular interest because,
with low density of rodent prey most of the time, weasels in this area
perhaps adapt their diets and may compete with ferret badgers. Dietary
and spatial relationships between the 2 carnivores were studied by scat
analysis and capture-and-recapture rates from March 1995 to August
1998. Diets of allopatric populations reported by others are referenced
for comparison. As expected, by switching to arthropod prey and shrews,
weasels in Guandaushi Forest consumed food items different from weasels
in alpine grasslands. Ferret badgers in Guandaushi and Fushan forests
consumed similar diets. The dietary overlap between the sympatric
weasels and ferret badgers was substantial; however, the occurrence
frequencies of vertebrates, arthropods, and earthworms in their diets
differed significantly. The major groups of arthropod prey of the 2
species differed; this might be related to their foraging behaviors.
Results from preliminary trapping (March to November 1995) suggested
that habitat segregation exists between weasels and ferret badgers in
the 3 regions (A-C) which differ in habitat types. This pattern was
confirmed in the main study period. More weasels were captured in
region A than in the other regions, while a reversed pattern was
observed for ferret badgers. Intensive human hunting in the spring of
1996 removed most of the marked animals. This provided an opportunity
to examine the significance of current competition on the observed
patterns of habitat segregation. Ferret badgers were almost eliminated
after the period of hunting. The occurrence of weasels was not
influenced by hunting, or by the disappearance of ferret badgers. This
suggests that there is no evidence for current competition between
weasels and ferret badgers, and coexistence is achieved by the
differences in habitat preference, diet, and foraging behaviors of the
2 species.
Key words: Interspecific
competition, Diet, Habitat segregation, Siberian weasel, Ferret badger.
*Correspondence: *Current address: Institute of Natural
Resource Management, National Dong Hwa University, Hualien, Taiwan 974.
Tel: 886-3-8662500 ext. 20314. Fax: 886-3-8662533. E-mail:
hywu@mail.ndhu.edu.tw
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