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Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid
Published on: August 8, 2017
A natural feeding experiment on a declining snowshoe hare population
Charles J Krebs1, Stan Boutin1, B S Gilbert1
1Department of Zoology, University of British Columbia, V6T 1W5, Vancouver, B.C., Canada.
Abstract:
A snowshoe hare (Lepus americanus) population on a 9-ha area was supplied with extra natural food by chopping down large white spruce (Picea glauca) and aspen (Populus tremuloides) trees throughout 3 winters from 1981 to 1984. Hares fed vigorously on the downed trees, but the phase of decline of the ten-year cycle occurred equally on control and experimental grids from 1981-1983, and we could detect no improvement in survival or reproduction on the food area. Growth rates were improved on the food grid during the first winter of the decline (1981-82). We concluded that food shortage is not necessary for the cyclic decline of snowshoe hares in the southern Yukon.
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