Abstract
Bobcats (Lynx rufus) are a native carnivore of Ohio, but by
1850 were extirpated or nearly so following pioneer
settlement of the state. The first modern record of a bobcat
in Ohio was an adult male killed in 1946. Distribution
accounts indicate that population re- establishment began
around 2000.
Today the bobcat is protected, and verified sightings, camera
surveys, and genetic analyses point to two subpopulations:
a fast growing, self-sustaining eastern subpopulation, and a
more slowly growing southern subpopulation. We evaluated
stomach contents of 120 adult and subadult bobcat carcasses
to help understand the disparity in subpopulation growth rates,
and inform proper bobcat management. We identified prey
species morphologically. We quantified prey species taken
and converted their frequencies to caloric intake estimates.
We calculated dry weight estimates of prey groups and
compared them between bobcat age classes, sexes, regions,
and across seasons.
We examined regional diet differences further by
calculating diet and condition indices. Eastern cottontail
(Sylvilagus floridanus) occurred most often. White-tailed
deer (Odocoileus virginianus) supplied the greatest caloric
value. Small rodents and insectivores were the most
common prey group. Adults consumed more, as defined
by weight, meso-mammals and large rodents than subadults
Diet composition did not differ between sexes. Weight
of large mammal intake differed significantly between
winter and summer, being greater in winter. Diet
composition and prey group weights did not differ regionally.
Dietary niche breadth of the southern subpopulation
indicated more even consumption of prey groups than
the eastern, whereas food niche overlap between regions
was high. The condition index of eastern and southern
bobcats also did not differ. We present the first rigorous
analysis of bobcat diet in Ohio, and infer that diet is not a
likely driver of disparate subpopulation growth rates of this
recovering species.
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