Tuleyome's Science Corner - The Elusive Wolverine!

Kristie Ehrhardt • June 28, 2023

Wolverine (Gulo gulo) by Getty

Have you heard the news? A wolverine was observed in California for only the second time in a century! The California Department of Fish and Wildlife (CDFW) confirmed that there were multiple recent and credible sightings; two in the Inyo National Forest and one in Yosemite National Park. CDFW believes that all three sightings were of the same individual and are calling the occurrence “extraordinarily rare”. So exciting!


To some, wolverines resemble little bears, however they actually belong to the same family (Mustelidae) as weasels, badgers, ferrets, otters, minks, martens and fishers. Their scientific name, Gulo gulo, translates to “glutton”; possibly for their voracious eating style. In North America, they are found primarily in the far north, cold, latitudes of Alaska and Canada but are also found in the Southern Rocky Mountains in Colorado, Wyoming, and New Mexico as well as the Cascade Range in Washington and a small portion of Oregon.


Wolverines are powerfully built and range from 18 to 40 pounds, males usually being larger than the females. They have strong, thick necks and a long 30 to 40-inch, tube-shaped body ending in a five to ten-inch tail. They are only about 18 inches high at the shoulder with powerful, stout and somewhat bowed legs and wide feet that have hair-covered soles; perfect for snowshoeing. Wolverines have small, rounded heads with powerful jaws full of strong teeth, two of them specialized to tear meat off of a frozen carcass. Their coarse dark brown coat is oily which helps repel snow and frost. They have lighter brown fur on their foreheads, the scruff of their necks, and continues down the left and right sides of their bodies. Like all members of the Mustelid family, wolverines have well-developed anal glands that secrete a foul-smelling fluid that is used for signaling to other wolverines and to mark territory. I’m quite certain those glands are why they have also been called “nasty cats” and “skunk bears”.


Primarily carnivores, wolverines are cunning and fearless hunters and are known for often taking down prey species more than twice their size. They’ve also been observed sparring with wolves and bears over resources within their range. When not picking fights with apex predators, their usual diet consists of small mammals, porcupines, livestock, moose, and deer but will consume limited amounts of vegetation and fruit when snow and food is scarce. They are also well-known scavengers, and a large component of their diet is comprised of leftover eagle, mountain lion and grizzly bear kills. Young wolverines are preyed on by gray wolves, mountain lions, golden eagles and grizzly bears but humans are responsible for taking the largest number of adults because of their water and frost repellant fur and threat to livestock. 


Wolverines are usually considered solitary animals with very large home ranges that can include up to 600 square miles. They may wander up to 15 miles a day foraging for food. Mating takes place from May to August and males typically form lifetime relationships with several females within their home range. Gestation time varies greatly depending on weather conditions and when the fertilized egg implants. Females dig dens in the snow, often using boulders or uprooted trees to help shelter from the cold. If food is scarce, females will not produce any young but if conditions are good, one to five (most often two to three) snow-white kits are born in the spring. The young develop quickly but remain with their mother (with occasional visits from the father) for up to about a year. Although primarily solitary, small family groups have been observed traveling and hunting together.


Biologists estimate that there are no more than 300 individuals in the lower 48 states. Although they’ve never been abundant, wolverines are essential to a healthy ecosystem and their habitat requirements include a deep snowpack. Research in North America has shown a positive correlation between the depth of the snowpack and the wolverine population. This is possibly because harsh weather conditions result in more feeding opportunities for wolverines with a greater number of available large ungulate carcasses. Although the wolverine is extremely rare in the United States, it is currently not listed as a special-status species under the Federal Endangered Species Act. Relatively good news though, it is listed as threatened under the California Endangered Species Act and is afforded full protection under the California Fish and Game Code. To learn more about the wolverines that have visited California please visit Tuleyome’s friend and conservation partner Defenders of Wildlife.


-Kristie Ehrhardt (kehrhardt@tuleyome.org)


Tuleyome Land Conservation Program Manager

RECENT ARTICLES

By Nate Lillge August 6, 2025
Bill Grabert is stepping down from his position as treasurer on Tuleyome’s volunteer Board of Directors – we thank him for his many years of service! Bill first joined Tuleyome as a staff member in 2016. His nature-based teaching influenced many youth over the years with school field trips throughout the Berryessa Snow Mountain National Monument region, from Redbud Trail to Conaway Ranch. As part of Tuleyome’s team of instructors for the California Certified Naturalist program, Bill inspired adults to care for the region. His love of the area began as soon as he graduated from college and began working as a geologist in Lake County. Bill has devoted his diverse knowledge and skillset to care for, steward, and enjoy California’s northern Inner Coast Range Mountains for many years. He will be missed on the Board but we look forward to seeing him on the trails! -Nate Lillge (Adventures and Engagement Director)  and Lyndsay Dawkins (Volunteer Tuleyome Board President)
By Bryan Pride August 6, 2025
Fifty-eight and a half million acres of America's wildest forests have been protected for nearly 25 years by the Roadless Rule, a conservation cornerstone that could soon disappear. Established in 2001, the Roadless Area Conservation Rule (RACR) , more commonly known as the Roadless Rule, designated "Inventoried Roadless Areas" (IRAs) across our nation's forests, prohibiting new roads from being built. Now, USDA Secretary Rollins wants to rescind it . From Alaska to California, the losses from this rollback would be massive. In Alaska, 92% of the Tongass National Forest could lose protection, threatening one of the world's most pristine ecosystems and the indigenous communities who call it home. California would lose protections across 4.4 million acres spanning 21 national forests , which has the potential to impact treasured places like Inyo, Shasta-Trinity, and the Berryessa Snow Mountain National Monument. Rule Born from Necessity, Not Ideology The Roadless Rule traces back to 1998, when U.S. Forest Service Chief Mike Dombeck saw the agency's vast road system as a major environmental and fiscal problem . To put this in perspective: the Forest Service maintains eight times more miles of road than the Interstate Highway System. The agency had too many roads to properly maintain for safety and environmental purposes, with poorly maintained roads contributing to erosion and other harms across national forests. The road maintenance backlog had ballooned to $8.4 billion while the agency received only 20% of the funding needed to maintain roads to environmental and safety standards. Dombeck proposed a moratorium on road construction in undeveloped forest areas across most of the National Forest System. The agency adopted an 18-month moratorium in February 1999 pending completion of an overall road management plan. Later that year, the agency undertook a rule making process to provide long-term administrative protection for roadless areas. The Forest Service conducted an extensive public involvement process that produced 1.7 million comments , with the majority favoring a strong national policy protecting roadless areas. The resulting Roadless Rule was not and is still not a blanket ban: it makes exceptions to allow access to non-federal land inholdings and pre-existing mineral leases, and allows logging to reduce fire risk, improve habitat or aid in the recovery of endangered species. What began as a fiscally prudent solution to an unwieldy road network became a cornerstone of forest conservation, one that Americans overwhelmingly supported then and continue to support today. The Administration's Claims vs. Reality According to USDA Secretary Rollins , the rule is “overly restrictive”, hinders fire prevention and responsible timber production, therefore the Rule poses “real harm to millions of acres of our national forests.” Rollins linked rescinding the Rule with Presidential Executive Order 14192, "Unleashing Prosperity Through Deregulation .” The reality is different. Rollins' claim ignores what's actually at stake. Roadless areas are essential ecosystems that provide clean air and water while keeping wilderness intact. They also serve as critical refuges for wildlife; 57% of America's most vulnerable species depend on roadless areas for habitat. For the 156 million Americans who visit national forests annually, these areas offer irreplaceable backcountry recreation experiences. Most strikingly, the administration's fire prevention argument is backwards. Scientific research reveals that 88% of wildfires are human-caused , and 95% of these fires start within half a mile of a road. Areas closest to roads experience 53% more fires than would occur by random chance. Less than 3% of wildfires start in wilderness areas more than a mile from roads. This research indicates that more roads through our forests are more likely to increase fires and would outweigh the effects of improving fire containment. While the administration claims roads improve fire response, fire management teams consistently identify inadequate resources and personnel shortages, not roads , as the primary barriers to effective wildfire management . Rather than building roads that increase fire risk, fire management experts advocate for investing in cultural and prescribed burns, fire mitigation and forest restoration, proven approaches that are underfunded but key to preventing future fires and reducing fire magnitude. What's Next? Rescinding the Roadless Rule will require a public comment period that has yet to be announced. This is when we can all share our views. Tuleyome will be following this issue closely and will be commenting. For more information on the Roadless Rule and how to participate in the public comment process or other advocacy opportunities, contact B ryan Pr ide .
By Kristie Ehrhardt August 6, 2025
The short answer is honestly, pretty much anywhere! Because the 344,476 acre Berryessa Snow Mountain National Monument (the Monument) is located in the rural areas of Colusa, Glenn, Lake, Mendocino, Napa, Solano and Yolo counties you will have a great view of the dark night sky, free from urban light pollution from virtually anywhere within its boundaries! The Monument is an easy drive from not only the metropolitan Sacramento area but also from the San Francisco Bay Area as well as the North Bay communities making it an easy day trip. If you’re here especially for the Perseid meteor shower though it might be a very long day since best viewing happens between the hours of midnight and early morning. If you’re adventurous and up for an all-nighter, be certain to pack plenty of water and snacks and be sure to pull over only where it is safe and you’re not blocking a road, especially when it’s dark. Also always keep safety in mind and look out for wildlife as the Monument is home to black bears, mountain lions, coyotes, tule elk and bobcats that may be traveling through the area as well. If you’d like to stay a night (or several), there are multiple developed campgrounds to choose from inside the Monument boundaries. If you’re up camping, check out The Blue Oaks Campground, Indian Valley Campground, Hunting Creek Campground, Deer Valley Campground, Lower Nye Campground, West Crocket Campground or Kowalski Camping area just to name a few of the sites available for overnight stays. Before you go though, please do check with the United States Forest Service or the Bureau of Land Management websites for details on the particular camping area you’re interested in as well as current conditions, requirements and fire restrictions. The Monument also offers primitive camping in the three wilderness areas located within the Monument boundaries. Cache Creek Wilderness, Cedar Roughs Wilderness and Snow Mountain Wilderness present nearly unlimited opportunities for dispersed camping or backcountry camping (areas located outside of designated campgrounds). Although camping is allowed and encouraged, these areas have no amenities such as tables, toilets, available water or waste removal and require you to pack out all trash and waste. There are no motorized vehicles allowed within Wilderness areas and they provide places for deep solitude with nature. Camping in Wilderness areas or other dispersed camping areas require visitors to understand and follow the Leave No Trace principles of outdoor recreating as well as planning ahead and knowing the area and what to pack. That said, other than the trees potentially blocking some of the night sky, you’re sure to avoid urban light pollution and have an unobstructed view of the night sky from practically anywhere within the Monument! -Kristie Ehrhardt ( kehrhardt@tuleyome.org ) Tuleyome Land Conservation Program Manager