Most bears are opportunistic omnivores, their diets consist of fruits,
other vegetative material, and in lesser amounts, mammals, fishes, an
d insects, Sloth bears (Melursus ursinus) an the only species of ursid
specifically adapted to feed on insects, especially termites and ants
. although they also feed on fruits when available, We studied diets o
f sloth bears in Royal Chitwan National Park, Nepal, where fruits are
available for ca. 4 months (May-August, and access to colonies of term
ites is reduced in lowlands that are flooded during the fruiting seaso
n. We analyzed frees and observed sloth bears foraging to investigate
their responses to changes in availability of food. Diets of sloth bea
rs were dominated by insects (> 90%), especially termites (greater tha
n or equal to 50%), from September through April, but they relied heav
ily on fruits from May through August. Seasonal movements between lowl
and and upland habitats seemed to be prompted mainly by availability o
f termites, Termites were more dominant in the diets of sloth bears in
our study than in a study conducted 20 years ago in Royal Chitwan Nat
ional Park and in studies in India, The dietary shift of sloth bears i
n Royal Chitwan National Park may have been related to changes in habi
tat conditions associated with relocation of people out of the Park. I
t appears that sloth bears, like other bears hut unlike other myrmecop
hagous mammals, can adapt their diet to changing food conditions.