The stomach contents were examined from 324 western Washington bobcats (Felis rufus) and 123 from eastern Washington taken by hunters from 1976 through 1980, for major prey items as well as sex- and age-related differences in diet. Western Washington bobcats ate primarily mountain beavers (Aplodontia rufa) (42% occurrence) and snowshoe hares (Lepus americanus) (26%). Within that population females ate larger quantities of smaller prey such as Douglas squirrels (Tamiasciurus douglasi) and lesser amounts of deer (Odocoileus sp.) than males. Bobcat diets in eastern Washington were more diverse; main foods consisted of lagomorphs (Sylvilagus nuttallii, Lepus sp.) (20%), red squirrels (Tamiasciurus hudsonicus) (15%), deer (11%), and voles (Microtus sp.) (11%). Age-related differences were most prevalent in this population, with adults consuming larger quantities of deer and larger prey than did kittens.
Knick, Steven T.; Sweeney, Steven J.; Alldredge, J. Richard; and Brittell, J. David
"Autumn and winter food habits of bobcats in Washington State,"
Great Basin Naturalist: Vol. 44
, Article 5.
Available at: http://scholarsarchive.byu.edu/gbn/vol44/iss1/5