U.S. fails to protect wolverines, again

U.S. fails to protect wolverines, again
Credit: Tambako the Jaguar via Flickr

Earlier this month, the United States Fish and Wildlife Service decided not to list wolverines in the lower 48 states as an endangered species. For years, researchers and environmental organizations alike have been scrambling to protect the iconic, snow-dependent predator that is facing the challenges of a changing climate. This decision is the latest in a string of rollbacks limiting the jurisdiction of the Endangered Species Act (ESA), threatening the future of a number of species.

It is estimated that there are fewer than 300 wolverines left in the contiguous U.S. Conservation groups such as Defenders of Wildlife and the Wolverine Foundation have been hard at work since the 1990s, when a number of nonprofits began suing the federal government to list wolverines on the ESA so they would receive protection. The Fish and Wildlife Service has consistently declined requests to classify wolverines as threatened or endangered. Under the Obama Administration, the agency proposed wolverine protection in 2014 due to a changing climate, only to later decide that the resulting habitat changes were not sufficient to warrant action. In 2016, U.S. District Court Judge Dana L. Christensen of Montana called for a reversal on that decision, which he called "arbitrary and capricious." This month's decision was the response to Christensen's request to have the listed.

"Once again, the proposed rule to list wolverines under the ESA was withdrawn, so they will continue to be federally unprotected," Michael Sawaya, a researcher from Sinopah Wildlife Research Associates, told GlacierHub.

Why Wolverines Matter

Wolverines hold a special place in many cultures. In traditional mythology of various Algonquian tribes, the wolverine Kuekuatsheu is known as a trickster and a thief. The University of Michigan has the wolverine as its mascot. Marvel Comics character James Howlett is the superhero "Wolverine" with a reputation—short in stature, but ferocious, with ripping claws.

In the wild, real wolverines live up to their pop culture renown. They are relatively small—ranging from 24 to 40 pounds—yet they can prey on animals many times their own size due to their strength. They resemble bears, but in reality, wolverines are the largest member of the weasel family. Their scientific name, Gulo gulo, comes from the word "glutton" because of their great love of food. As solitary scavengers, wolverines cover a lot of ground in their pursuit of food, often 15 miles a day.

Because of their nomadic movements, wolverines occupy many different habitats. They can be found traveling in alpine, tundra, or boreal zones. High mountains and snow are important components of their habitat requirements, which makes them particularly well-suited for glacial living—Female wolverines burrow deep into the snow in late winter to make dens where they give birth to their cubs. In addition, males often bury their food in snow to keep it fresh.

Challenges Facing Wolverines

Despite their celebrity status, wolverines have faced a history of challenges. For one, they have a characteristic coat that has made their fur desirable for legal and illegal trapping. Wolverine fur is well adapted to frost conditions, so the pelts are often used to trim cold-weather clothing. In the 1920s, the wolverine population in the Rockies was almost eradicated completely. Restrictions on hunting and trapping have helped wolverine populations recover.

Habitat destruction is another challenge for wolverines. Wolverines often inhabit large territories in which they search for food and mates. For this reason, wolverines are particularly susceptible to human encroachment like that caused by the building of roads, winter recreation resorts and other developments.

Emerging research has focused on mapping the spatial distribution of wolverines so that scientists can better understand the availability of habitat to support healthy populations. A paper published in Wildlife Management in March tried to determine the link between suitable habitat and wolverine population density. Lead author Paul Lukacs, a professor of wildlife biology at the University of Montana, used cameras and hair snares across Idaho, Montana, Washington, and Wyoming to distinguish the higher quality undisturbed habitat from human-modified land, and to map the population density of wolverines. This data provides a baseline for wildlife managers who can use it to trace distribution in the future.

Another paper from February focused on how to separate the different populations of wolverine in the U.S. and Canada. "My collaborators and I are working on a project to examine wolverine population connectivity and gene flow in the western U.S. and Canada," said Sawaya, who was one of the authors of the paper. "The results of this work will help to identify specific areas on the landscape where we can apply conservation measures such as wildlife corridor protection or highway mitigation, like wildlife crossing structures, to maintain or restore wolverine population connectivity."

A bill was introduced to the House of Representatives last January which proposed modifications to the Endangered Species Act in ways that could further challenge the wolverine protection effort. The ESA has been integral in supporting wildlife for 40 years. In this time, 99% of the species that were listed as endangered or threatened were saved from extinction, according to the Natural Resource Defense Council. The law also is widely supported across parties; a 2018 survey found that four out of five Americans supported the act.

Proposed changes to the ESA include a new definition of "habitat" which may make it harder to protect critical areas. In August, the Fish and Wildlife Service proposed two definitions for the term, which had previously been undefined in the act. The narrower definition would include only areas where the species currently lives, excluding areas that cannot currently support the species, whereas the wider definition included all areas a species depends on for survival, regardless of its current state of habitability.

"The new definition of 'habitat' would make it harder to protect unoccupied areas, which are important for a species that needs room to expand," said Taylor Jones, an advocate at WildEarth Guardians.

There is also an economic component to the proposed changes. The ESA originally mandated that best available science should guide species protection decisions, without reference to economic impacts. The new change allows for economic impacts to be considered, which may generate political ill-will against species protection projects. "But all of this is moot if the wolverine does not get listed in the first place, which is definitely what the administration is attempting to do," Jones told GlacierHub.

"This weakening of the ESA will have dire consequences for wildlife already struggling to survive," said Rebecca Reilly, a legal director from the Natural Resources Defense Council in a press release. "If we fail to protect habitat that species need, before long, we won't have those species anymore. We will continue fighting to protect wildlife for future generations."

These changes to the Endangered Species Act have faced backlash from Congress and the public. When the rollbacks were first announced in January, 800,000 public comments were submitted to oppose the changes, and 105 members of Congress and 34 senators wrote letters to the Department of the Interior.

Policy Implications

Since the current administration has proposed multiple detrimental changes to the law over the past four years, some organizations are calling upon presidential candidate Joseph Biden to take a stand to protect endangered species. The Sierra Club has expressed the importance of Biden developing a robust extinction plan to complement his existing climate proposal. Other organizations like Animal Wellness Action, a lobbying group, see legislation such as the Captive Exotic Animal Protection Act, which Biden sponsored during his senate tenure, as a positive indicator of his stances should he take office.

This latest blow to protection means that activists, organizations, and scientists will renew their efforts to ensure the survival of the species. New research is highlighting how to best protect wolverines, but should be backed by protection under the Endangered Species Act. The outcome of the upcoming election will make a large difference to the survival of the species in the lower 48 states.


Explore further

US officials: Climate change not a threat to rare wolverine

More information: Paul M. Lukacs et al. Wolverine Occupancy, Spatial Distribution, and Monitoring Design, The Journal of Wildlife Management (2020). DOI: 10.1002/jwmg.21856
Journal information: Journal of Wildlife Management

Provided by Earth Institute, Columbia University

This story is republished courtesy of Earth Institute, Columbia University http://blogs.ei.columbia.edu.

Citation: U.S. fails to protect wolverines, again (2020, October 29) retrieved 14 May 2021 from https://phys.org/news/2020-10-wolverines.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
3 shares

Feedback to editors

User comments