Extent, causes and timing of moose calves mortality in western interior Alaska

Timothy O. Osbourne; Thomas F. Paragi; James L. Bodkin; Andre J. Loranger; W. N. Johnson

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USGS · 70180494

Extent, causes and timing of moose calves mortality in western interior Alaska

Timothy O. Osbourne·Thomas F. Paragi·James L. Bodkin·Andre J. Loranger·W. N. Johnson

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Abstract

We examined the causes and timing of moose ( Alces alces ) calf mortality during 1988 90 in 2 locations in western interior Alaska. Annual survival rates of all calves in 1988 (0.34, n = 42) and 1989 (0.29, n=47) on the Nowitna National Wildlife Refuge (NWR) and in 1990 (0.25, n = 62) on the Koyukuk NWR were not significantly different. Survival rates of male and female calves were not significantly different during any year. Annual survival of single calves was significantly higher than that for twins in 1989 (0.56 vs. 0.20) and 1990 (0.37 vs. 0.21), but not in 1988. Black bears ( Ursus americanus ) killed 40% of all calves. Wolves ( Canis lupus ) killed 9% of the calves, unknown predators killed 8%, grizzly bears ( Ursus arctos ) killed 3%, and 5% died from other causes.

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Alces Article

Source-reported bounding extent: 64° to 66° latitude; -159° to -153° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Timothy O. Osbourne, Thomas F. Paragi, James L. Bodkin, Andre J. Loranger, W. N. Johnson. 1991. Extent, causes and timing of moose calves mortality in western interior Alaska. https://pubs.usgs.gov/publication/70180494

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