Fecal samples were examined to estimate black bear (Ursus americanus) diet in northeastern Oregon during 1998 and 1999 to determine the important food items. Mean estimated relative volume of food items in 621 scats was 35% grasses, 24% insects, 16% fruit, 11% soil and wood, 10% animal remains, and 4% leaves and stems. During June, remains of mule deer (Odocoileus hemionus) and elk (Cervus elaphus) occurred in 44% of the scats in 1998 and in 25% in 1999, at a time when other protein-rich food sources were unavailable. Between May and October, >40% of all scats collected in each month contained insects, and 98% of those scats collected in July contained insects. A significantly higher volume of insects occurred in scats in 1999 compared to 1998, probably because berries were scarce in 1999. Of the 434 scats containing insects, 40% contained carpenter ants (Camponotus spp.), 45% other small ants (Lasius sp, Tapinoma sp., Aphaenogaster sp.), 36% forest ants (Formica spp.), and 23% yellowjackets (Vespula spp., Dolichovespula sp.). Because these ant species are all log-dwelling, management for coarse woody debris is an important consideration in maintaining this important food resource for black bears in northeastern Oregon
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Title
The importance of vegetation, insects, and neonate ungulates in black bear diet in northeastern Oregon
Creators
Evelyn L. Bull (Author)
Torolf R. Torgersen (Author)
Tara L. Wertz (Author)
Publication Details
Northwest science., Vol.75(3), pp.244-253
Academic Unit
Northwest Science
Publisher
WSU Press
Identifiers
99900502957501842
Copyright
In copyright ; openAccess ; http://rightsstatements.org/vocab/InC/1.0/ ; http://purl.org/eprint/accessRights/OpenAccess