Document: JAN-3-69-34

Distribution of bark beetles in a harvested landscape.

PARK, J.*

University of Calgary, Calgary, Alberta, Canada. ¹

Abstract:
Heterogeneity in landscapes is expected to affect the distribution of animals. Here, I examine how variation in tree density (due to harvesting) and tree species composition affects the distribution and settlement of bark beetles (Scolytidae). Decreased tree density may influence where bark beetles fly, due to changes in microclimate and ability to detect host chemicals. Differences in stand composition may also affect fight preferences based on the probability of finding a suitable host. This project is based in the boreal forest of northwestern Alberta, Canada. I examined four harvest levels: 0% harvest, 90%, 80%, and 50%, in each of four different stand types: Aspen dominated, conifer dominated, aspen dominated with conifer understory, and mixed. Between April and August 1999, two 12-funnel Lindgren traps baited with bark beetle pheromones were placed in each stand with beetles collected every two weeks. Beetles were then identified and counted to determine any habitat preferences. The number of captured striped ambrosia beetle (Trypodendron lineatum) differed significantly among the four stand types (p<0.05), with the mixed stands being most preferred. However, there were no significant differences found between the four harvest levels (p>0.05). These preliminary results show that landscape structure may influence the distribution of bark beetles.

Keywords: forestry, harvest levels, bark beetles, distribution, habitat suitability

This abstract is being presented at: 10:30 AM in session:
Poster Session #12: Disturbance Ecology.