By Thomas McNamee, The New York Times, July 14, 2017
In March 2016, the United States Fish and Wildlife Service proposed removing the Yellowstone grizzly bear population from the list of threatened species. The uproar was ferocious. Conservationists, scientists, 125 Indian tribes and some 650,000 citizens expressed concern about the move.
Why? Because, foremost, the service’s biologists and administrators believe that the population has recovered to self-sustainability. And it has in fact grown a lot since 1984, the year I published “The Grizzly Bear,” when mother bears numbered in the low 30s — the brink of extirpation. The Department of the Interior now claims that “an estimated 700” grizzlies inhabit the Greater Yellowstone Ecosystem — a vast wildlands centered on the world’s first national park but also including Grand Teton National Park, portions of six national forests, three national wildlife refuges and other federal, state, private and Indian lands.
A true recovery could be the greatest triumph yet for the Endangered Species Act of 1973, which is itself politically endangered. The states surrounding Yellowstone National Park — Idaho, Montana and Wyoming — have been pressing for the delisting for years, so that they can assume management of the bears outside the boundaries of the Yellowstone and Grand Teton parks. All three states plan to issue hunting licenses, which would be few in number but a major victory in the culture wars of the mountain West.
This is not the first time the feds have tried to delist the Yellowstone grizzly. They did it in 2007 and were met with a barrage of legal fire from conservation groups, which won in court and again on appeal. The court restored the bear to full protection in 2009, with a stinging rebuke of the government’s scientific claims.
So is it a true recovery this time? Nearly all conservation biologists outside government say that an absolute recovery will never be possible for the Yellowstone grizzly population.
The Yellowstone grizzly’s food system is collapsing. One of the bears’ most important sources of nutrition has been the seeds of the whitebark pine, but the tree is under a double attack.
The native mountain pine beetle has historically been kept in check by periodic deep freezes, but there haven’t been any of those for years now, and this beetle has been killing pine species throughout the Rocky Mountains. The other attacker is the nonnative white pine blister rust, a deadly fungus that attacks the stems of the trees. More than 80 percent of the whitebarks are now dead or dying in the Greater Yellowstone region.
Until recent years, early each summer there were vast runs of spawning cutthroat trout up the tributaries of Yellowstone Lake — a high-fat feast for grizzlies. Since the illegal introduction in the 1980s of nonnative lake trout, however, which feed on juvenile cutthroats, the spawning runs are down by 90 percent.
A little-known but significant food source is an annual aggregation of army cutworm moths at high altitude in the Absaroka Mountains. One bear can eat up to 40,000 moths — 20,000 calories’ worth — in one day. The moths depend on moist microhabitats that are drying as summers continue to warm.
A less well understood but equally grave danger is that Yellowstone grizzlies live on what is effectively an island, its surrounding “sea” being devoid of grizzlies in all directions. Island populations are subject to inbreeding and hence lowered reproduction rates, and grizzlies are among the least fecund of mammals to start with. When island populations fall into reproductive decline, there are no adjacent populations to resupply them.
Many of the thousands of public comments on delisting have focused on the renewal of hunting. Very few people can stomach the image of a grizzly bear shot down — somehow it’s not like an elk or a deer. Management by the states is supposed to be rigorously overseen by the federal authorities, and over-hunting would seem to be unlikely under the proposed guidelines. Yet pursued by even a small number of hunters, Greater Yellowstone’s grizzlies would become much less visible for the millions of visitors who want only to see one.
Because they’re so hard to find in any case, grizzly bears are formidably hard to count, and a number of eminent scientists reject the government’s population claims. David Mattson, a recently retired visiting senior research scientist at the Yale School of Forestry and Environmental Studies, maintains that the population has “grown very little if at all during the last decade. Most of the claimed increase is an artifact of changes in method” of counting, “a fact often obfuscated by the agencies promoting delisting. And the population has been declining for at least three years.”
The only way Yellowstone’s grizzly bears can be expected to thrive in the long run is for their ecosystem to be connected by a corridor of occupied habitat to other grizzly populations — the one centered in Glacier National Park to the north and others up the Rocky Mountain chain to Alaska. That’s still possible, if grizzly hunting remains forbidden and the connecting lands are safeguarded in perpetuity against incursion and development, which they are not today.
Classification of the Yellowstone grizzly as a threatened species is set to expire at the end of July unless the courts step in again. Taking away federal protection now — with the bears’ food sources plunging and their ecosystem isolated — is an act of either deceit or folly.
Classification of the Yellowstone grizzly as a threatened species is set to expire at the end of July unless the courts step in again. Taking away federal protection now — with the bears’ food sources plunging and their ecosystem isolated — is an act of either deceit or folly.
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