Beaver Studies, Isle Royale National Park, 1986

Shelton, Philip

Total colonies with food piles was 204 and they were sized in an attempt to quantify food pile size for comparison with surveys done in Voyageurs National Park and for comparison in future studies at Isle Royale. The total number of beaver present on Isle Royale in the fall of 1986 was calculated to be approximately 1400 animals. Beaver numbers are thought to be influenced primarily by wolf predation. Report lists tree and shrub species cut by beaver for use as food. Report speaks of the complexity of the effect of beaver activity on plant succession. Contains maps showing locations of active beaver colonies. The library's bound copy of this report includes a series of color prints and duplicate slides. These prints and slides illustrate changes in vegetation, including those influenced by beaver, on the northeast portion of Isle Royale from the 1960s and 1970s through the mid 1980s. Total document including maps, prints and slides is 44 pages.