UBC Theses and Dissertations
Influence of forest edge, elevation, aspect, site index, and roads on deer use of logged and mature forest, Northern Vancouver Island. Willms, Walter David
This study was proposed by the B. C. Fish and Wildlife Branch to evaluate the effect of forestry practices and forest characteristics on deer use of logged and mature forests. The specific factors studied were "time since burning", "elevation", "site index", "aspect", "forest edge", "roads" and "vegetation". The effect of elevation and aspect on deer use was studied for both the mature and logged forest while the other factors were considered only for recently logged areas. The location of this study was the Nimpkish Valley, northern Vancouver Island in British Columbia. This area was selected primarily because it had a large population of Columbian black-tailed deer (Odocoileus heinionus columbianus Richardson), active logging, and variable terrain. The deer response to "time since burning", "elevation", and "site index" was generally determined by plant quality and climate. The importance of vegetative quality to deer is reduced when the climatic conditions become favorable for the animals. Therefore, during a mild winter the deer are less dependent upon the greater plant production found on areas with later seral stages, lower elevation, and higher site index, than they are during a severe winter. Similarly, on an annual basis, high plant production is less important on the warm south aspect than it is on the colder north aspect. Two types of forest edges were studied, the upper which is parallel to the elevation contours and the adjacent which is perpendicular to the elevation contours. The upper edge influences deer use of areas, both inside and outside the forest, by maximizing use near the edge. Deer use declines with increasing distance from the edge. The only apparent effect of the adjacent edge on deer use of recently logged areas was to depress use at the edge. This also occurred at the upper edge. Roads affect deer use of recently logged forests by increasing use adjacent to the road but decreasing use on the road and the road edge. It appears that deer use the road only for travel. Deer exhibit preference for a variety of plant species. The use with increasing cover of an individual species is generally parabolic while the use with increasing cover for all species combined is generally linear. Furthermore, maximum use occurs on those areas where the number of species present is greater than 1. The response of deer to increasing elevation, in the mature forest, is positive on the south aspect and zero, or nearly so, on the north aspect. This relationship is similar to that which occurred on recently logged areas following a mild winter.
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