Photo: U.S. Fish and Wildlife Service
Last week I attended the biannual meeting of the Yellowstone Ecosystem Subcommittee (YES) of the Interagency Grizzly Bear Committee. YES is comprised primarily of representatives from federal and state agencies charged with grizzly bear recovery and management. This was a pivotal meeting, as the Interagency Grizzly Bear Study Team revealed results of its long-awaited analysis of grizzly bear foods. The Study Team began the analysis nearly two years ago after a court ruled that the U.S. Fish and Wildlife Service (USFWS) had not adequately justified its conclusion that the steep decline of whitebark pine throughout the Yellowstone ecosystem would not adversely affect the survival of the grizzly bear, when the agency removed the Yellowstone grizzly from the Endangered Species List.
Over the past 18 months, the Study Team has conducted research to determine what foods grizzlies may be substituting for whitebark pine seeds and cutthroat trout (two of four major grizzly foods rich in protein that have steeply declined in the past decade), and how the bears are faring. A key question is whether those alternative foods pack the same kind of calories and nutrition that the bears need to maintain healthy reproductive and survival rates. The Study Team’s preliminary conclusions are that grizzlies are finding comparable foods and that the leveling off of the growth rate over the past decade is not so much due to the decline of whitebark pine, but rather because we’ve reached the carrying capacity of the ecosystem for grizzly bears. Based on these preliminary findings, federal agencies are gearing up to again propose removing federal protections from Yellowstone grizzly bears.
If bears are indeed doing fine, that’s good news. However, the Study Team’s results are preliminary — much of the research is still being reviewed by other scientists – and significant questions about the status and trends of the Yellowstone grizzly population have not yet been answered. Last summer, research by Dan Doak and Kerry Cutler raised serious questions about the federal government’s grizzly population estimates and asserted that the population may actually be in decline. Federal agencies dispute this, but have not released the data that their (higher) population estimates are based on, so their conclusions of a healthy grizzly population cannot be independently verified. Also, a key study that looks at where alternative foods are located has not yet been completed by the Study Team as part of its analysis. Whitebark pine lives at high elevations that keep bears away from people; switching to other foods – whether elk killed by hunters, or backyard bird feeders — could bring bears into closer proximity to humans, resulting in a much higher risk of conflicts and mortalities. There may be substitute foods, but if grizzlies die at a higher rate when trying to utilize those foods, that’s important to know.
Additionally, in its analysis the Study Team saw a decline in the percent of body fat for females, which directly affects reproductive capacity, from 2007-2010. This result could be the result of the study’s small sample size; as the Study Team notes “ Clearly, additional research is required to ascertain if this downward trend is in fact real….” , but it adds to the uncertainty about trends in the grizzly population and the need for taking a closer look.
One of the biggest issues that must be resolved, in order for the Yellowstone grizzly population to be fully recovered, is the geographic isolation of Yellowstone’s grizzly bears. At the YES meeting government scientists confirmed that there has been no genetic exchange between Yellowstone grizzlies and any other grizzly bear population. Think of an island of 500-600 people that never has any new migrants: it doesn’t bode well for the long-term health of the population. It’s the same with bears. Right now, the government’s plan to get around this problem is to truck in a bear every 10 years or so from another grizzly population to Yellowstone. Such ‘solutions’ are not true recovery. Natural connectivity must be established between Yellowstone and other populations, like Northern Continental Divide grizzlies, and habitat protections must be extended outside the current core area to include these linkage zones.
Despite this list of uncertainties and lack of connectivity between populations, the majority of YES members voted to conditionally approve the Study Team’s conclusions (provided no substantive issues come up in the scientific review of its analysis that is currently underway) and thus begin the process of once again removing Endangered Species Act protections from the Yellowstone grizzly.
Sierra Club believes the risk of removing federal protections for the Yellowstone grizzly is too great at this time. There must be a higher degree of confidence in the actual status and trends of the grizzly population. There must be a greater understanding of where alternative foods are, and what the increased risk is to grizzlies attempting to utilize these foods. The Yellowstone population needs to be connected naturally to other populations in order to ensure the long-term genetic health of grizzly bears in the Yellowstone ecosystem. And habitat protections must be extended to areas critical to grizzlies’ ability to find food and mates in an ecosystem that is being significantly affected by climate change, development, and other factors.
Misguided decisions and the premature removal of endangered species protections could quickly have a severe impact on grizzly bears, undoing decades of recovery efforts. Grizzlies are the 2nd slowest reproducing mammal in North America – females are typically at least 5 years of age before they reproduce; they only have litters once every 3 years, and generally a litter is 1 to 2 cubs. So we too must move slowly. Grizzlies are the ultimate symbol of wildness and one of the animals we treasure most. Their comeback since the 1970s has been a success that we need to keep moving forward. If the Study Team is right, and the Yellowstone grizzly population is healthy and bears are able to find adequate substitute foods and thrive, then that is indeed a cause for celebration. But let’s make sure they are truly recovered before we take away the very protections that have saved them from extinction.
Bonnie Rice, Senior Representative – Greater Yellowstone
 It is unclear how the IGBST is differentiating foods from carrying capacity. Carrying capacity is related to available foods; if key food sources are declining, the carrying capacity of the ecosystem is reduced.
 Doak, D. F. and Cutler, K. (2013), Re-evaluating evidence for past population trends and predicted dynamics of Yellowstone grizzly bears. Conservation Letters. doi: 10.1111/conl.12048
 Schwartz et al (2013), Body and Diet Composition of Sympatric Black and Grizzly Bears in the Greater Yellowstone Ecosystem. Journal of Wildlife Management DOI: 10.1002/jwmg..633