Volume 92, June 2014, Pages 133–142
Highlights
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- We assessed habitat where grizzly bears consumed ungulates, and at random sites.
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- Bears fed on ungulates in forested areas, close to edges, and where cover was high.
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- Consumption site choice reflected a strategy to avoid detection by scavengers.
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- Large carcasses were more likely to be detected, and caching was more likely for medium prey.
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- The resource pulse and food-spoilage caching hypotheses were not supported.
Prey
consumption forms a large part of prey-handling time, and knowledge of
where prey is ingested can inform management of predator–prey systems.
Safeguarding habitats that promote prey consumption could enhance
populations of facultative or obligate carnivores of conservation
concern. We investigated habitat characteristics at 124 sites where
radiocollared adult grizzly bears, Ursus arctos (N = 9)
consumed ungulates, and we contrasted these sites with paired random
sites. We developed a priori models incorporating the potential effects
of ungulate and plant food distribution as well as risks of detection by
humans and other carnivores on consumption site choice, and evaluated
which factors best explain grizzly bear food-caching behaviour.
Ungulates were consumed in forested areas, close to edges, and where
horizontal cover was high, whereby vegetation impeded visibility of the
ungulate carcass. Distance to roads had no effect on the distribution of
prey consumption sites, but carcasses were further from trails than
expected. Models incorporating presence/absence of key non-ungulate bear
foods had little weight of evidence (wi ≤ 0.01).
Food-caching behaviour did not appear to be related to variation in
resource availability or risk of food spoilage but was significantly
influenced by prey size. Although bears chose sites that minimized
detection risk, spent more time at larger carcasses and cached 75.9% of
ungulates, 50% of consumption sites had other carnivore sign, which was
more likely to be present at large carcasses.
Keywords
- carnivore;
- conservation;
- detection risk;
- grizzly bear;
- handling time;
- human access;
- kill habitat;
- Ursus arctos
Copyright © 2014 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
