CODY, Wyo. — On April 12 of last year, state Game and Fish officers shot dead a dangerous nuisance known as Bear #G92, after the grizzly repeatedly broke into buildings searching for food on a ranch near here.
The 5-year-old male was the first of 19 grizzly bears to die in the region surrounding Yellowstone National Park and one of 50 killed in the lower 48 states, making 2004 the worst year for grizzly mortality since the animal was added to the endangered species list in 1975.
The death rate in Yellowstone, where the grizzly population is estimated at 600, was 2 1/2 times higher than the 15-year average.
Most worrying to wildlife biologists was the fact that females made up 60% of the dead.
Nonetheless, the U.S. Fish and Wildlife Service is preparing to remove Yellowstone's grizzly bears from the endangered species list this year. Moreover, new management plans may allow hunting of the bears outside the park.
The Yellowstone contingent is the largest of a handful of grizzly populations in the contiguous states and the only one facing imminent removal from the endangered species list. Their range encompasses Yellowstone, Grand Teton National Park and nearby lands in Wyoming, Montana and Idaho. The law protects the bears in Yellowstone, part of Grand Teton and in a circle of land outside known as the "primary recovery area."
A formidable symbol of the American wilderness, and a hugely popular public attraction in Yellowstone, the grizzly bear would be the biggest animal to come off the endangered species list since the California gray whale was delisted in 1994.
Despite the record number of dead bears last year, the Fish and Wildlife Service contends the grizzlies, whose population has more than doubled in the three decades it has been on the list, no longer need the special protection afforded by the law.
"We're victims of our own success," said Chris Servheen, Fish and Wildlife's grizzly bear coordinator.
"The bears are expanding their numbers and their range. They are now in places they haven't been in 80 or 100 years. These mortality rates are to be expected when bears punch out into areas where there are more people."
But Servheen emphasizes that the bears will be closely monitored after they are delisted. If their numbers drop below 500, a management review will be triggered. An overall decline of more than 4% or a 1.2% annual drop in the female population would also trigger a review, Servheen said, and that could lead to an emergency relisting.
Bear experts believe that an isolated population of fewer than 500 could lose its genetic diversity and become vulnerable to disease and birth defects.
Some biologists, notably Dave Mattson, a specialist on population assessment who has been studying the Yellowstone grizzlies since 1979, are wary of managing by numbers. "We really don't have any precise ways to count bears or track their growth and decline," Mattson said. "Even if you start with 500 bears, an annual decline of 2% to 5% over 15 to 30 years could take them down to 200."
According to estimates at the time, there were between 150 and 220 Yellowstone grizzlies when they were placed on the endangered species list.
Mattson, who works for the U.S. Geological Survey, said he had not taken a position on delisting, but he worried that not enough was known about comparatively new threats such as climate change and the proliferation of nonnative species that could deplete some of the bears' food sources by 90%.
Some opponents of delisting contend that last year's mortality rate underscores the bears' vulnerability to encroaching development. They argue that once exempt from the highest level of federal protection, the bears will be safe only inside Yellowstone and Grand Teton national parks, areas too small to sustain a viable population of grizzlies.
In 2001, the Bush administration shelved a plan to reintroduce grizzlies in a wilderness area along the Idaho-Montana border, despite strong public sentiment in favor of the move. Many experts believed it would have been a major step in assuring the long-term survival of grizzlies because the isolated Yellowstone bears would have been able to intermingle with the introduced population.
How the Yellowstone bears fare could well be the most conspicuous test case of the Bush administration's policy on endangered species.
The administration wants to modify the Endangered Species Act to make it harder to add to the list and easier to remove species from it. It also wants to make it harder to set aside "critical habitat" -- wildlife sanctuaries covering millions of acres where commercial and industrial development is restricted.