Study: Wolverines need refrigerators

Jul 12, 2012
This is a wolverine. Credit: Mark Packila, WCS

Wolverines live in harsh conditions; they range over large areas of cold mountainous low-productivity habitat with persistent snow. The paper suggests wolverines take advantage of the crevices and boulders of the mountainous terrain, as well as the snow cover to cache and "refrigerate" food sources such as elk, caribou, moose and mountain goat carrion, ground squirrels and other food collected during more plentiful times of year. These cold, structured chambers provide protection of the food supply from scavengers, insects and bacteria. In addition, the refrigerated caches increase the predictability of available food resources, reduce the energy spent by females searching for food while in lactation phase, and decrease the time mothers spend away from cubs.

The paper appears in the current edition of the Journal of Mammalogy and was co-authored by Robert M. Inman of WCS, Audrey J. Magoun of Wildlife Research and Management, Jens Persson of the Swedish University of , and Jenny Mattisson of the Norwegian Institute for Nature Research.

"People don't normally think of insects and microbes as being in competition for with ," said lead author Robert Inman of the 's North America Program. "But in fact, bacteria will devour an unprotected if that source is available."

Through an extensive literary review, the authors noted that wolverine reproduction is confined to a brief period of the year, and the lactation phase in females (February through April) corresponds to a period of low availability of . Wolverines, which are opportunistic , have adapted by amassing food caches during the preceding winter months when food is more readily available. Without the cached food supply or an unforeseen alternative (such as a winter-killed ungulate), early litter loss occurs.

Inman said, "Understanding why and how wolverines exist where they do and the various adaptations they have evolved to eke out a living will better inform population management strategies and conservation of the species."

Climate change will play a key role in management planning for the conservation of wolverines, the authors say.

In a study published in 2010, wolverine biologists demonstrated a relationship between the areas where wolverines exist (their distribution) and persistent . The first theory advanced was that wolverines must have deep snow available in springtime so that they can give birth to their small cubs in a warm, secure den. The newly released study suggests that other factors related to climate and snow pack, such as competition for food, may also be involved in explaining the limits to wolverine distribution.

Because of their dependence on snow pack, wolverines were recently listed as warranted for protection under the Endangered Species Act due in large part to the threat of climate change reducing distribution and habitat connectivity. The authors say that a deeper understanding of how and why wolverines use snow pack the ways they do is critical to understanding how climate change will impact survival and reproductive rates.

"Shedding light on the specific mechanism of how climate will affect wolverines is important in order to know what to do to help them hold on," said WCS's North America Program Director, Jodi Hilty.

Inman and co-authors published a study in December of 2011 on the spatial ecology of wolverines in the Journal of Wildlife Management. This latest paper represents the second of several that will help to inform a conservation strategy for the species.

Explore further: Adjusting wind power production during migration season saves bats

add to favorites email to friend print save as pdf

Related Stories

Origins of wolverine in California genetically verified

Apr 29, 2009

A wolverine first photographed by a remote-controlled camera on the Tahoe National Forest in February 2008 is most closely related to Rocky Mountain populations, according to a team of 10 federal, state and university scientists.

Will lemmings fall off climate change cliff?

Apr 20, 2007

Contrary to popular belief, lemmings do not commit mass suicide by leaping off of cliffs into the sea. In fact, they are quite fond of staying alive. A bigger threat to the rodents is climate change, which ...

Where will grizzly bears roam?

Jun 21, 2011

The independent assessment, written by WCS Senior Conservation Scientist Dr. John Weaver, is a compilation and synthesis of the latest information on these species – and how climate change may affect ...

Recommended for you

Tropical fish a threat to Mediterranean Sea ecosystems

7 hours ago

The tropical rabbitfish which have devastated algal forests in the eastern Mediterranean Sea pose a major threat to the entire Mediterranean basin if their distribution continues to expand as the climate ...

Moroccan city outlaws olive trees

8 hours ago

A Moroccan city has banned olive trees because of pollen-linked allergies and set an end-of-the-year deadline for residents to remove them, media reports said Thursday.

User comments : 0