Forest fragmentation impact studied

CHAMPAIGN, Ill., Oct. 24 (UPI) -- A U.S. study suggests parasites can contribute to the decline of most species living in fragmented forests, while enhancing the prospects of others.

University of Illinois researchers said their study is the first to look at how forest fragmentation increases the burden of infectious parasites on animals.

The study focused on black-and-white colobus monkeys and red colobus monkeys living in western Uganda, which has less than 5 percent of its original forest cover, with some fragmented forest areas being as small as 2 acres.

UI Pathobiology Professor Thomas Gillespie and Colin Chapman of McGill University discovered populations of black-and-white colobus monkeys appear to be stable in the Ugandan forest remnants, while their cousins, the red colobus monkeys, are in decline.

One of the differences between the two species affecting their vulnerability to parasitic infection is that red colobus monkeys congregate and live in large groups, covering wide areas in search of specific foods.

"The black-and-white colobus tend to feed on whatever's dominant," said Gillespie.

The ability to eat well under a variety of circumstances enhances their ability to withstand parasitic infections, he said.

The researchers' detailed findings appear in the current issue of the American Journal of Primatology.