BioOne.org will be down briefly for maintenance on 17 December 2024 between 18:00-22:00 Pacific Time US. We apologize for any inconvenience.
How to translate text using browser tools
1 December 2012 Black Bear (Ursus americanus) Foraging on Black Cottonwood (Populus trichocarpa) Catkins in Southeast Alaska
Mary F. Willson
Author Affiliations +
Abstract

Black Bears (Ursus americanus) in southeastern Alaska forage intensively on seed pods and male and female catkins of Black Cottonwood (Populus trichocarpa), often breaking many branches from the trees. We examined the relationship of tree damage to tree size and sex, and to content of selected nutrients in the catkins. Tree damage was related to tree girth: medium-size trees were more heavily damaged than small or large trees, possibly because more branches can easily be reached from a safe perch near the trunk. Overall, female trees were more heavily damaged than males. Foraging intensity was not clearly related to the content of important elements (N, P, K, Ca, C) in catkins and seed pods. Concentrated use of cottonwoods in the study area may occur because high human density offers some protection of small Black Bears from larger bears, and medium-sized cottonwoods are common in this recently deglaciated, early-successional area.

Mary F. Willson "Black Bear (Ursus americanus) Foraging on Black Cottonwood (Populus trichocarpa) Catkins in Southeast Alaska," Northwestern Naturalist 93(3), 211-219, (1 December 2012). https://doi.org/10.1898/11-22.1
Received: 16 September 2011; Accepted: 1 April 2012; Published: 1 December 2012
KEYWORDS
Alaska
black bear
Black Cottonwood
foraging behavior
Populus trichocarpa
Ursus americanus
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top