September 29, 2014

Wolverines in the Lower 48 have had a tough go of it in the quest to list them under the Endangered Species Act (ESA). Conservation organizations started requesting protection for wolverines in 1994, and three times the U.S. Fish and Wildlife Service (FWS) decided – despite mounting evidence to the contrary – that wolverines did not deserve to even be considered for listing. It wasn’t until 2013 that things finally looked hopeful: the FWS issued a formal proposal arguing that wolverines should be listed as “threatened” due to the threat of climate change impacting their habitat. But that basis for hope recently disappeared – and left conservation advocates wondering just how badly a species needs to be doing in order to get protection under the ESA?Wolverine, © Kalon Baughan

An internal FWS memo from the Denver regional office surfaced this summer, recommending that wolverines should not be listed because of uncertainties regarding the impacts of climate change. The final decision from the Director of FWS to deny listing on those grounds arrived a few weeks later on August 13, with FWS arguing that experts can’t predict with certainty the impacts climate change will have on wolverines. The problem? The agency’s own experts – field biologists who have worked for several years on the wolverine listing decision – had already given the opposite recommendation. They were entirely convinced by the best available science that wolverines deserved the protection of the ESA as a “threatened” species due to the threat of climate change but unfortunately, that point of view did not carry the day with the final agency decision.

And what could climate change mean for wolverines? With snow levels in the West expected to continue to decline over time, wolverines will find that the deep, persistent snowpack that they depend on for den sites is dwindling. This prediction is based on solid science and regarded by most experts as a serious threat to wolverines.

It’s pretty hard to understand why FWS would dismiss the findings of its own experts on likely climate change impacts, or ignore other types of threats to the species that are widely acknowledged to be valid concerns. The truth is that wolverines are in serious trouble from a number of threats, along with any impacts coming from climate change. These animals already face a host of other problems, including a small population (fewer than 300 in the entire lower 48 states!) and low genetic diversity.

Wolverine, © Kalon BaughanFurthermore, the FWS asserts that the wolverine population in the Lower 48 is currently stable or slightly increasing, even though there is no published research to back up this assertion. Biologists estimate a current total wolverine population of fewer than 300 individuals, and that an average of only 35 animals each year are actually reproducing and contributing to the next generation. While new tools have recently allowed us to spot some wolverines in regions where they had not been seen for decades, these anecdotes are not proof that the population is expanding. Lone individuals here and there do not mean that breeding pairs are abundant. It is reckless to assume a population is increasing when the science isn’t there to prove it!

The FWS is supposed to make decisions based on the best available science. In this case, FWS chose be dismissive of the likely impacts from climate change and ignored a multitude of other threats to the wolverine. Defenders and other conservation groups will now challenge this flawed decision in federal court and we will keep you informed about our progress in getting the wolverine protection under the ESA.

Meanwhile, Defenders will continue our extensive work on the ground to help protect wolverines. We work to protect habitats important to wolverines and other species, support and perform monitoring and research, educate the public, and rally around possible reintroductions of this elusive predator.

It is a fundamentally American value to protect our land, air, water, and wildlife – that’s why Congress enacted the ESA. If we’re not willing to protect one of the rarest mammals in the Lower 48, a species with fewer than 300 individuals left south of the Canadian border and one of the lowest successful reproductive rates known to mammals, how imperiled does a species have to be to gain federal protection?

We currently have a petition to tell Secretary of the Department of the Interior Sally Jewell – who oversees the Fish and Wildlife Service – to reconsider the serious threats to the survival of wolverines and immediately reverse this unsupportable decision. Please take part!

And for a little love to wolverines, here’s a great image made for Defenders by Erik Brooks of Harts Pass comic strip!

I Heart Wolverines, © Erick Brooks

Kylie Paul is the Rockies & Plains Representative at Defenders of Wildlife


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