A Comparison of beaver foraging behaviour in two national parks

Abstract

Strategies adopted by foraging herbivores are influenced by the availability of resources. Beavers (Castor canadensis) are important ecosystem engineers, having the ability to modify the landscape through the consumption of selected resources. Predictions of central place foraging theory are that fewer food items are taken and that increased selection takes place by species and by size of food items at greater distances from the central place. These predictions were tested in Voyageurs National Park, Minnesota and Terra Nova National Park, Newfoundland. Cut and uncut trees were monitored during May-December, 2008 along transects surrounding 15 inland beaver ponds. Beavers selected fewer stems, larger diameter stems, and fewer different forage categories with increasing distance from ponds at both parks. The history and present state of vegetation communities are important to understanding beaver foraging and the overall role that beavers continue to have in boreal mixed-wood forest communities.