Optimal foraging behavior of Castor canadensis along Carp Creek and O'Neal Lake in the northern lower peninsula of Michigan.

Abstract

The foraging behavior of Castor canadensis was explored at two differing sites in the northern lower peninsula of Michigan. The first site was located along Carp Creek, which consisted of thick flora. It was dominated by Alnus rugosa and Betula papyrifera. The second site was located along the shore of O'Neal Lake, was less dense, and consisted primarily of B. papyrifera, A. rugosa, and Populus grandidentata. As expected, C. canadensis did show a preference in the species of trees in which it attacked at both the Carp Creek and the O'Neal Lake sites. Alnus rugosa and Betula papyrifera were preferred in both sites, while Populus grandidentata was also selected in the O'Neal Lake site. As expected, it was found for both sites that more trees were attacked closer to the body of water from which C. canadensis foraged. This was due to accessability of the trees at close distances and the increased risk of predation at great distances. No relationships were found between the diameter of the trees attacked and the distances from the water that they were located in the Carp Creek site or the O'Neal Lake site. When considering all the species of trees in the transect areas, C. canadensis showed no preference in the diameter of trees selected at either site.