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Abstract |
Top carnivores play an important role in maintaining energy flow and functioning of the ecosystem,
and a clear understanding of their diets and foraging strategies is essential for
developing effective conservation strategies. In this paper, we compared diets and prey
selection of snow leopards and wolves based on analyses of genotyped scats (snow leopards
n = 182, wolves n = 57), collected within 26 sampling grid cells (5×5 km) that were distributed
across a vast landscape of ca 5000 km2 in the Central Himalayas, Nepal. Within the
grid cells, we sampled prey abundances using the double observer method. We found that
interspecific differences in diet composition and prey selection reflected their respective
habitat preferences, i.e. snow leopards significantly preferred cliff-dwelling wild ungulates
(mainly bharal, 57% of identified material in scat samples), whereas wolves preferred typically
plain-dwellers (Tibetan gazelle, kiang and argali, 31%). Livestock was consumed less
frequently than their proportional availability by both predators (snow leopard = 27%; wolf =
24%), but significant avoidance was only detected among snow leopards. Among livestock
species, snow leopards significantly preferred horses and goats, avoided yaks, and used
sheep as available. We identified factors influencing diet composition using Generalized Linear
Mixed Models. Wolves showed seasonal differences in the occurrence of small mammals/
birds, probably due to the winter hibernation of an important prey, marmots. For snow
leopard, occurrence of both wild ungulates and livestock in scats depended on sex and latitude.
Wild ungulates occurrence increased while livestock decreased from south to north,
probably due to a latitudinal gradient in prey availability. Livestock occurred more frequently
in scats from male snow leopards (males: 47%, females: 21%), and wild ungulates more frequently
in scats from females (males: 48%, females: 70%). The sexual difference agrees
with previous telemetry studies on snow leopards and other large carnivores, and may
reflect a high-risk high-gain strategy among males. |
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