SPOKANE — Despite 20 years of recovery efforts, the last wild herd of woodland caribou in the Lower 48 states continues to struggle for survival.

Only 41 of the caribou, a close relative of the reindeer, were counted in the 2003 annual census within the greater Selkirk Mountains north of Spokane.

This caribou herd was listed as endangered by the federal government in 1983, and remains under pressure from loss of habitat and predation by cougars.

"The population of caribou has been stable for a couple of years now," said Tom Buckley of the U.S. Fish and Wildlife Service in Spokane.

But the herd is not self-sustaining and the number of caribou remains low despite transplants brought in by wildlife officials. Between 1987 and 1998, 113 caribou from other regions were brought to the Selkirks. Without the transplants, the herd would already be extinct, researchers contend.

Importing caribou from Canada and Alaska into the Selkirks has not been as successful as wildlife officials hoped. Some of animals left the ecosystem and moved north. Others were killed by predators, were poached or died of unknown causes, officials said.

Scientists believe the herd must reach 200 caribou to survive on its own long term. They estimate that, historically, the herd had 200 to 400 animals.

There is no deadline for removing the animals from the endangered species list, said Fish and Wildlife scientist Suzanne Audett.

Mountain caribou were once found across the northern tier of the United States, from Washington to New England. But logging and other human encroachment wiped out their habitat. Now they are limited to a remote area of the Idaho Panhandle, northeastern Washington and southern British Columbia.

For a time in the 1990s the Selkirk herd was being devastated by a rising cougar population. But wildlife managers in the U.S. and British Columbia successfully reduced the number of cougars in the recovery area in recent years, Buckley said. That has reduced the number of caribou killed by the mountain lions.

Focus is now shifting to habitat issues.

Logging of old growth forests is hurting the caribou, because their winter diet is almost exclusively lichens that only grow on those tree branches, Buckley said.

It takes about 50 years for trees to grow tall enough to be above the snow line and support lichens. Another 50 years are needed before the lichens are abundant enough for caribou to eat.

Rein Atteman of The Lands Council, a Spokane-based environmental group, said more old-growth forest needs to be reserved for the caribou.

"The adult survival rate is higher in those tracts of old growth," Atteman said. "We are asking for the entire Selkirk Mountain range on the U.S. side, including state land in Idaho, to be set aside,"

Just as important is restricting logging, motorized vehicle use and other human encroachment on caribou habitat, he said. Also, deer, elk and moose are competing with caribou for food in the region, and their numbers may need to be reduced, environmentalists contend.

In 1994, the goal of 50 caribou in the recovery area was set.

"The recovery team is still short on that goal," Atteman said.

Environmentalists worry the animals are on their way to extinction, Atteman told the International Mountain Caribou Technical Committee meeting earlier this month in Spokane.

Researcher Rob Weiglus of Washington State University told the committee his studies found that cougar numbers in the recovery area have declined, from 1.5 cougars per 100-square kilometers to 1 per 100 square kilometers.

But at the same time, Heiko Wittmer of the University of British Columbia said habitat continues to become fragmented. Woodland caribou do poorly when forests are cut up into small parcels by roads or by logging operations, he said.

Caribou do not reproduce very quickly. The females do not breed until they are about 3 1/2years old and produce only one calf every other year. The reproduction rate is among the lowest of the deer family.

When the time for birth nears, a pregnant cow will leave the lower elevation where food is abundant and travel to steep, snowy ridges to have her calf. It is believed that this behavior occurs to avoid predators.

But it exposes the vulnerable calves to rain, snow, cold and winds. Only about three calves out of 10 survive each year.

Male caribou live about 7 to 8 years. Females live slightly longer, to 10 or more years.

Recovery of caribou within the Selkirk Mountains is a cooperative effort of agencies from Washington and Idaho, the U.S. government and the British Columbia Ministry of Environments.

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