By Louisa Willcox
At recent grizzly bear meetings in Bozeman, federal and state managers announced plans to remove Endangered Species Act protections for Yellowstone’s threatened grizzly bears next year. The delisting push, which is being driven by states that want to control and hunt bears, is justified in part by new government claims that grizzly population numbers have jumped from an estimated 600 during past three years to 741 bears.
For many reasons, however, it’s far too soon to conclude that Yellowstone’s charismatic bear population is viable enough to again allow hunting. Chief among those concerns are: serious questions about the science behind the new estimates of bear numbers; increased threats to bears, including the fact that climate-driven changes to their food sources are resulting in more conflicts with humans; and the fact that Yellowstone is an isolated remnant of the area grizzly bears once roamed.
There’s no doubt that a nearly 20 percent jump in bear numbers sounds impressive. But this jump is not based on an actual count of bears – it’s based on a revision of the methods used to estimate the population. And independent scientists can’t fairly evaluate the claim because the government has steadfastly refused to release the taxpayer-funded data upon which the new population numbers are based.
Because grizzlies have the slowest reproductive rate of any mammal in North America, it is not biologically possible that the population has increased so much, especially given the deaths of more than 100 bears during the last three years. In other words, the jump is largely an artifact of changes in counting methods – paper bears rather than real bears.
This is why an open and transparent process of scientific inquiry is so important. The integrity of the scientific enterprise relies on creating and testing alternative hypotheses to explain the data. It is essential to know with great confidence how the population is actually doing, and what the future trends are most likely to be, in order for the public to make an informed decision on whether removing federal protections is appropriate. As James Madison said in 1822, “a popular government, without popular information, or the means of acquiring it, is a prelude to a farce or a tragedy or both.”
While there is doubt about the numbers, from a bear’s point of view there is no doubt about what is happening to the ecosystem: it is unraveling. Three of the four traditional mainstays of the grizzly bear’s diet – whitebark pine, cutthroat trout and elk – have either collapsed or are in decline. And drought and climate change are likely to worsen the bear’s future prospects. More....