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Predation on Moose Calves by European Brown Bears |
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| Authors: | JON E SWENSON BJØRN DAHLE HELENA BUSK OLE OPSETH THOMAS JOHANSEN ARNE SÖDERBERG KJELL WALLIN GORAN CEDERLUND |
| Institution: | 1. Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway
Department of Biology, University of Oslo, P. O. Box 1066 Blindern, NO-0316 Oslo, Norway;2. Department of Conservation Biology, Swedish Agricultural University, P.O. Box 7002, SE-750 07 Uppsala, Sweden Agriculture Ministry, SE-103 33 Stockholm, Sweden;3. Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway Länstyrelsen i Dalarna, P.O. Box 86, SE-790 91 Idre, Sweden;4. Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway Norwegian Nature Inspectorate, NO-9321 Moen, Norway;5. Department of Plant and Environmental Science, Göteborg University, P.O. Box 461, SE-405 30 Göteborg, Sweden;6. Department of Conservation Biology, Grimsö Wildlife Research Station, SE-730 91 Riddarhyttan, Sweden Swedish Game Management, P.O. Box 5260, SE-711 98 Ramsberg, Sweden |
| Abstract: | Abstract: In North America, brown bears (Ursus arctos) can be a significant predator on moose (Alces alces) calves. Our study in Sweden is the first in which brown bears are the only predator on moose calves. Bears and moose occurred at densities of about 30/1,000 km2 and 920/1,000 km2, respectively, and bears killed about 26% of the calves. Ninety-two percent of the predation took place when calves were <1 month old. Bear predation was probably additive to other natural mortality, which was about 10% in areas both with and without bears. Females that lost their calves in spring produced more calves the following year (1.54 calves/F) than females that kept their calves (1.11 calves/F), which reduced the net loss of calves due to predation to about 22%. |
| Keywords: | Alces alces brown bear kill rate moose neonates predation Sweden Ursus arctos |