Note: Repost from the old blog.
In stunning news, researchers at Oregon State University snapped a photo of a possible California Wolverine (Gulo gulo luteus) north of Lake Tahoe between Truckee and Sierraville in the Tahoe National Forest. This is the first proven detection of a wolverine in California in 86 years – the last one was shot dead in 1922.
The actual location was on Sagehen Road in the Sagehen Creek area at the Sagehen Creek Field Station. This station is in the Sagehen Creek Experimental Forest. The field station itself, where the photo was taken, is at 6,375 feet.
California wolverines seem to exist more at lower elevations as one travels north in California. Towards the south in the Sierra Nevada, they are found more at 8,000-9,000 feet if sightings are any guide. It is 8.4 miles north of Truckee and 20 miles north of Lake Tahoe. Sagehen Basin itself ranges from 5,900 to 8,700 feet.
Despite much theory stating that wolverines hate any human presence, the area where the photo was taken is only 1.5 miles away from a major highway, Highway 89.
An excellent brochure about the Sagehen Creek area, listing hydrology, geology, geography, botany and biology, including insects, reptiles, amphibians and mammals, is here. Katie Moriarty, the graduate student who took the photos, was probably staying at the field station, which has excellent lodging facilities for researchers and has served as the study area for more than 80 theses and dissertations.
A photo of the first California Wolverine documented since 1922. This wild region where they were found in being proposed as a wilderness area by Senator Barbara Boxer. The probable proposed area is the proposed Castle Creek Wilderness Area . The photo shows the wolverine from the rear view.It is probably next to a Red Fir.
In the background is what appears to be a White Fir and the tree in the foreground looks like some kind of pine. In this part of the Sierras, the Red Fir Zone (where this photo was probably taken) starts around 7,000 feet elevation.A much larger version of this pic, too large to put on this blog, is available here on the researchers’ website.
The area is in the central Sierra Nevada Mountains in northern California.
What they mean by confirmed sighting is that it has to be backed up by a photo or a specimen. They say fur or scat also counts, but apparently that is not true, as California wolverines were confirmed via fur samples from Del Norte Siskiyou and Shasta Counties by the California Department of Fish and Game in the late 1980’s.
I know that a wildlife biologist saw one above Bishop, California in 1980, and I understand that there have been a number of other sightings by biologists. There have been quite regular sightings of these very elusive animals in California down through the years.
Live wolverines have also been trapped in far northern Washington state in the Cascades near the Canadian border in the past couple of years.
The natural range of the California wolverine extends in California only and has been separated from wolverines in the Washington Cascades for at least 2,000 years, according to genetic studies. As a subspecies, it is controversial and is not yet accepted across the board by the scientific community.
The first description of a California wolverine was published in the Field Columbian Museum of Zoology Zoological Series in 1903 (rare online copy here). You can see in the description of the type specimen from Mount Whitney that the California wolverine was much paler than the wolverine normally found in the rest of North America.
The California wolverine is a subspecies of wolverine that split off from other branches about 2,000-11,000 years ago. The California wolverine formerly ranged into the Cascades of California and even over towards the Coast in the Northern Coast Range all the way down to San Fransisco.
It then ranged down the Sierra Nevada Mountains all the way down to the southern end of the range at the Southern Sierra Wilderness, where they were last sighted in the 1950’s. Monache Meadows is usually given as the southern end of the range, but the Southern Sierra Wilderness is south of there.
Based on sightings, it was felt that the California wolverine had declined to a very low level near extinction in the early 1930’s and then the population had been increasing slowly ever since. William Zielinski is an expert on wolverines who participated in this study.
Thomas Kucera, a researcher at San Fransisco State University, undertook a wolverine survey in the state in the early 1990’s with bait stations and cameras.
They saw quite a few animals, including many martens, a few fishers, coyotes, bears, bobcats, and mountain lions, but they found no wolverines in the exhaustive survey. The guarded conclusion then was that California wolverines were extinct in the state. I did a web search on the California Wolverine recently and most experts were saying that the the general conclusion was that they were gone from the state.
I never thought this animal went extinct in the state because I was aware of regular sightings, mostly around the Sierra National Forest, which is near where I lived for 16 years. Around 1990, tracks were sighted near Courtright Reservoir at 8,200 feet near Kings Canyon National Park in the southern Sierra National Forest. A local Forest Service biologist had seen the tracks.
California wolverine tracks were seen here, at Courtright Reservoir, in 1990. The tracks were verified by a Forest Service biologist, but this counts as an unverified sighting, since tracks don’t count (Go figure!)
In 2004, apparent wolverine tracks were photographed on the trail up to Gabbot Pass west of Bishop by a group of hikers from Australia.
Possible wolverine tracks photographed in July 2004 at Gabbot Pass on the Sierra Crest west of Bishop by Australians David Noble and Lizzy Went. There have been consistent sightings in the area west of Bishop and east of Courtright Reservoir and just north of Kings Canyon National Park over a 28-year period now.
The view from Gabbot Pass is at 12,240 feet, where an unverified sighting of wolverine tracks was made in July 2004.
There was also a sighting in 1994 in Kaiser Pass near Huntington Lake at about 9,200 feet in the Sierra National Forest. The local Forest Service biologist said she believed the man who saw it.
Kaiser Pass east of Huntington Lake in the High Sierras. I was here in the summer of 1991 when I drove a relative and a friend to a drop-off at Florence Lake further on down the road. The road across Kaiser Pass was truly horrid and terrifying at the time and I doubt if it has been improved. It’s beautiful up there though, and if you get the chance, check it out. A unverified sighting of a California wolverine was reported here in 1994.
In 1979, a wolverine was spotted at Hilton Creek Lakes near Mt. Stanford (map). This area is east of Lake Edison and west of Tom’s Place in the John Muir Wilderness on the Sierra National Forest.
Hilton Creek Lakes in the John Muir Wilderness, elevation 10,705 feet. This area is near Stanford Peak. Access is out of the Rock Creek Trailhead on the East Side of the Sierras. A wolverine was seen here in 1979.
In September 2010, a wolverine was seen on the Pacific Crest Trail near Red Cones, which is near Devil’s Postpile and Mammoth Mountain.
In 1992 and 1993, a Biology teacher at the local high school in Oakhurst, Gary Spence, saw them two years in a row at Spotted Lakes (9,100 feet) in the far southeast corner of Yosemite National Park near the National Forest border. Spence is a good biologist and he used to go out on field surveys with the local Forest Service biologist.
In 2004, there was a reported sighting north of Polly Dome Lakes at 8,500 feet near Tuolumne Meadows in Yosemite National Park.
The Polly Dome Lakes near Lake Tenaya, where there is an unverified California wolverine sighting from 2004. I was here in the Summer of 2003. I stayed at White Wolf campground and paid money for a cabin. Any lazy, old or out of shape person can do this, even you!
You drive your car into the campground and stay in a cabin! All you need is money. I even, at age 46, hiked up the murderous trail to Lukens Lake. You can do this too! All you need to do is get off your butt. Along the way, I saw a shrew running along the forest floor. Come on, when do you ever see such a thing?
I took a drive one day down the Tioga Road to Tuolumne Meadows and went by Lake Tenaya, where the scenery looks about like this. This part of Yosemite is beautiful! If you are in the area, take a drive up there in the summertime. There’s a nice highway, you don’t have to worry about a thing, and you are in the most beautiful scenery on Earth.
Around 1990, a wolverine was spotted on the back side of Lembert Dome in Tuolumne Meadows in the middle of winter.
In 2005, a wolverine was spotted in Tuolumne Meadows, again in winter. The observer had taken zoology courses at UCLA for seven years.
Another was seen in Lyell Canyon at 8,900 feet in eastern Yosemite in 1997.
Lyell Canyon in Yosemite National Park, where there was an unverified California wolverine sighting in 1997. This area is east of the Tuolumne River and southeast of Tuolumne Meadows. The Pacific Crest Trail runs through here, and Sierra Nevada Bighorn Sheep are known to exist in this area. Bighorns have been being devastated lately by mountain lions. This is poorly understood.
It appears that Bighorns are staying up high to avoid the mountain lions instead of migrating downslope as they normally do. Hence, they are being killed by avalanches when they stay in the high elevations for the winter. Bighorns and mountain lions evolved together, and it is not known why this dynamic is occurring. Domestic sheep grazing in this area is totally pointless, and is ongoing.
Also in 1997, there was an unverified sighting of a wolverine off Highway 120 just after it passes Tioga Pass to the east, looking down into Lee Vining Canyon. The wolverine was sighted running away about 1,000 feet down below.
Lee Vining Canyon just east of Tioga Pass. I was near Tioga Pass in August 2003, but I did not continue down the road a ways to the pass itself. In 1997, there was an unverified sighting of a wolverine running away over a snowy ridge about 1,000 feet below near where this photo was taken. Tioga Pass is at 9,943 feet, so the wolverine was at about 9,000 feet.
North of Yosemite, on the Stanislaus National Forest, there was a wolverine sighting on the Emigrant Wilderness in 1990.
North and east of Yosemite, in the Hoover Wilderness Area, wolverines are said to persist. One was spotted there near the Virginia Lakes in the 1970’s.
In 2001, a biologist spotted a wolverine somewhere on the Stanislaus National Forest, but the location was not given.
There have also been wolverine sightings in the Pacific Valley area north of the Carson-Iceberg Wilderness, an area that connects the Carson-Iceberg with the Mokelumne Wilderness on the Eldorado National Forest. Pacific Valley (map) is being considered as an addition to the Carson-Iceberg. The date of this sighting is not known.
There has also been a sighting of a wolverine four miles west of the Snow Canyon Research Natural Area on the Amador Ranger District of the El Dorado National Forest. This area is near Highway 88 about three miles south of Carson Pass, and part of it is in the Mokelumne Wilderness.
In 1978, there was an unverified sighting of a wolverine near Disaster Peak (10,047 feet) in the Sonora Pass area in the Carson-Iceberg Wilderness. I went through the Sonora Pass area in 1987.
The area to the west of Lake Tahoe continues to get sightings. A sighting was reported from Island Lake in the Desolation Wilderness Area just southwest of Lake Tahoe in 1994. Another sighting was from the north shore of Loon Lake Reservoir near Lake Tahoe on the El Dorado National Forest on July 7, 1994. This is a few miles to the west of the Desolation Wilderness.
A Panorama of Loon Lake Reservoir west of the southwest shore of Lake Tahoe. A wolverine was seen here in 1994.
In addition, there are wolverine sightings to the southeast, near South Lake Tahoe. In 1990, a wolverine was sighted 2 miles from where Highways 50 and 89 meet in South Lake Tahoe and the southern end of the lake (map). This area is close to Emerald Bay, DL Bliss and Sugar Pine Point State Parks. I have been to all of these parks on the shore of Lake Tahoe, but that was 30 years ago. It’s a beautiful place.
That very wild area north of Lake Tahoe, especially the Granite Chief Wilderness, was considered to be one of the most likely places for the California Wolverine to be found due to the very high number of sightings in the area. In 2000, there was an excellent sighting of tracks in this area.
For example, a wolverine was sighted in 1991 in the Euer Valley on the Truckee Ranger District. A wolverine was seen in 1992 in the Harding Point area, northeast of Sierraville, and this sighting was confirmed by tracks.
On the Downieville Ranger District, a wolverine was sighted in 1989 in the Haskell Peak area, another was seen in 1990 in the Upper Sardine Lake area, one was seen in 1993 in the Gold Lake Road and Salmon Lakes Road area, and in 1998, one was seen near Bassett’s Station.
On the Foresthill Ranger District, there were two wolverine sightings by wildlife biologists. The first was seen in the Robinson Flat area in 1980, and the second was seen in 1992 in the Granite Chief Wilderness Area. All of these sightings were on the Tahoe National Forest.
In addition, in the Duncan Canyon Proposed Wilderness Area, there have been two wolverine sightings in recent years. This area is near French Meadows Reservoir.
Also on the Tahoe, three years ago, a wildlife biologist at the San Fransisco State University’s Sierra Nevada Field Campus near Bassetts, 32 miles northwest of where this photo was taken, saw a California wolverine. That is also on the Tahoe National Forest.
San Fransisco State University’s Sierra Nevada Field Station, 32 miles northwest of the Sagehen Creek photo site. There was an unverified sighting of a California wolverine here by a wildlife biologist in 2005.
About 25 years ago, the district ranger of the Sierraville Ranger District, near where this photo was taken, saw a California wolverine running down a road in the middle of the day.
There was also an undocumented sighting of a California wolverine 4 miles west of Truckee on Highway 80. It had scavenged road kill from this busy interstate highway and was dragging it down into the rocks to eat it. I traveled over Donner Pass in Summer 1979. It’s quite a beautiful area.
Approaching Donner Pass from the east. Highway 80 does not actually cross Donner Pass itself anymore, but actually goes 2 miles to the north at Euer Saddle. Donner Pass gets 415 inches of snow a year, making it one of the snowiest places in the US. Wind gusts of over 100 miles an hour are common during winter storms.
This is where the famous Donner Party tried to cross into California in the winter of 1846-47, became trapped, turned cannibal and half of them died of starvation. There was an undocumented sighting of a California wolverine here in 2004 dragging roadkill off the highway to eat it. There have been sightings north of Tahoe National Forest. Forest Service employees have made quite a few wolverine sightings in both the northern Tahoe National Forest and in the southern Plumas National Forest in recent years.
In 1993, a wildlife biologist on the Lassen National Forest sighted a wolverine in a den near the headwaters of Deer Creek at 5,000 feet (note that even sightings by wildlife biologists are said to be unconfirmed). This area is near Child’s Meadow and is next to the southern border of Lassen National Park.
Child’s Meadow at the headwaters of Deer Creek near the southern boundary of Lassen National Forest. A wildlife biologist spotted a wolverine in a den here in 1993.
Those who keep saying that California wolverines no longer exist ought to note that all sightings are regarded as unconfirmed, even those by wildlife biologists.
Tracks are also regarded as unconfirmed sightings. This area was in private hands and was recently purchased by the Nature Conservancy. Incredibly, the private landowner wanted to put a golf course in here!
Lassen National Park’s draft management plan proposes to reintroduce wolverines to the park.
There have also been sightings at Green Island Lakes, a National Forest Service Research Station at 6,100 feet in the Lassen National Forest in Plumas County.
Wolverines have also been sighted around Eagle Lake on the Lassen National Forest.
There have also been two sightings on the Collins-Almanor Forest, a large commercial forest northwest of Lake Almanor. This area is where the northern Sierra Nevada meets the Southern Cascades.
On the North Coast and in the California Cascades, there have been wolverine sightings in Del Norte and Trinity Counties east through Siskiyou and Shasta Counties.
In Shasta County, recent sightings are known from the Big Bend area north of Montgomery Creek near Burney Falls. There have been sightings in the lower Pit River watershed near Carberry Flat and on the Lassen National Forest at Bald Mountain and Kosk Creek Basin.
There were a number of sightings in this area from 1960 to 1974. For instance, there was a sighting six miles north of Hyampom Road near Hyampom in 1974. Sightings are ongoing. A wolverine was seen in Corral Bottom, 10 miles north of Hyampom, in the winter of 1989. It ran along the road in the snow for a hundred yards or so, then disappeared into a water cave in the three foot deep snow. Wolverine tracks were seen two times in Hyampom in the winter of 2010. Hyampom is located east of Eureka in the Trinity Alps.
The very deep forest on the road between Hyampom and Hayfork in Trinity County. A wolverine was spotted here in 1974.
In 1980, Forest Service personnel on the Shasta-Trinity National Forest observed a wolverine on the Lower McCloud River at Chatterdown Creek several miles downstream from the Nature Conservancy McCloud River Reserve. This sighting was in Shasta County.
The Lower McCloud River at Ah-Di-Nah near the Nature Conservancy Reserve. Note the very deep forest here. A wolverine was sighted near here by Forest Service workers in 1980. Photo by Lily G. Stephen.
The most recent sighting of a wolverine on the Klamath River was at Dillon Creek on the Klamath National Forest, 20 miles below Happy Camp (map). This sighting occurred in Siskiyou County. The elevation here appears to be only 500 feet. Wolverines occur in deep forest at much lower elevations on the North Coast.
Dillon Creek on the Klamath National Forest is a Class V+ rapids stream. This area is extremely rugged, and it is almost impossible to hike out of this canyon. A wolverine was sighted in this area fairly recently.
There were numerous wolverine sightings in the Klamath Mountains of California in the 1980’s and 1990’s.
Wolverines in this part of California tend to use lower elevations and are not so restricted to the subalpine zone.
According to new data, the wolverine in this photo is from the Rocky Mountains and is not a California wolverine. Reginald Barrett, dean of furbearer studies in the West, told me in an in a recent interview that he felt that this wolverine had come down from Idaho through the Great Basin into California.
Nevertheless, in my opinion, California Wolverines never left this state.
Wolverines are known to exist in Idaho, Montana, Oregon, Washington, Wyoming, Colorado, North Dakota and Michigan. Wolverines are thought to be secure and not endangered in the Idaho Sawtooths at the moment.
They were formerly present in many other states in the US, including Arizona, New Mexico, Utah, Nevada, South Dakota, Nebraska (!), Iowa (!), Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, Maryland (!), New York, New Hampshire, Vermont and Maine. A good historical and present range map is here (Figure 2).
There are 14 different subspecies of the wolverine. The species is more or less circumpolar, ranging from northern Canada to Alaska across Siberia to Finland, Sweden and Norway. There are 500 wolverines in Scandinavia and 1,500 in Russia. They formerly occurred all through Norway and into southern Sweden, Estonia, Latvia, Lithuania and northeastern Poland.
The southern populations have been extirpated except for a wolverine recorded in Estonia in 1986, which means they may be reclaiming former habitat there.
In Sweden they are limited to the far northwest where their numbers are growing but their distribution is irregular. There are 265 wolverines in Sweden. The population declined from 1870 to 1970, when they received protection. Since 1970, the population has been growing.
There are 150 wolverines in Norway. 100 years ago, they ranged through the whole country, but since then, they have been aggressively hunted to where they were limited to the north. Since 1970, they have recolonized the south-central area and remain in the north. Protections are in place.
In Finland it is an endangered species with a population of about 115. At the turn of the century, 50 wolverines a year were killed there. They then declined until they were protected in 1982. A good report on wolverines in Scandinavia is here.
They are still common, though declining, in Russia, where they are common in the far east. The are most common in the Komi region (wolverine population 880). With the return to capitalism, they have undergone radical declines in the Kola (pop. 160) and Karelia (wolverine population 80) regions. The chaos and insanity of the return to capitalism have probably resulted in unrestricted hunting in Russia.
There is estimated to be a population of 200 wolverines in the Greater Khingan Range of Inner Mongolia in northeast China. It is thought to be declining. There formerly was a population to the west in the Altai Mountains in Sinkiang Province, but they have not been seen there since the 1990’s. Poaching is thought to be the major threat in China.
They were formerly found through much Canada but are now uncommon in Ontario (though increasing), extremely rare in Quebec and extirpated from Labrador. An excellent report on wolverines in Ontario can be found on the Internet on the Wolverine Foundation’s site here.
In Manitoba and Saskatchewan, they are declining and are now found only in the northern parts of the provinces. They used to be found all through the forested areas of Alberta but are now limited to the Rockies and remote areas in the north.
They are common all through British Colombia except for the agricultural areas of the south and throughout the Yukon and the Northwest Territories. A subspecies on Vancouver Island is thought to be extirpated. It has not been seen since 1992. There is a horrible amount of logging occurring on that island.
Populations in the north are estimated at 4,200 south of the 66th parallel. They may be more common in the Yukon than anywhere else on Earth other than the North Slope of Alaska. A great report on wolverines in Canada is here.
They are common in Alaska but sporadic on the islands of the southeast.
Wolverines have a reputation for being solitary and antisocial creatures. It is said that they are barely social enough to reproduce. Nevertheless, there is a good bond between mothers and kits. Kits are known to stay with the mother for up to 14-15 months. That is a very long time for a mammal.
The notion that wolverines are like orangutans in being antisocial loners in being challenged. Findings out of research in Idaho’s Sawtooths have shown a three-year old male traveling with a male juvenile, showing him the ropes, how to avoid predators and find food. They also saw a grown male playing with a juvenile female in a meadow.
Previously it was thought that females alone raised kits, and males had nothing to do with their offspring like mountain lions and so many other mammals. Females reportedly remember their natal dens and recover them when their mother dies. Males may assume the role of patriarch by fathering kits with multiple females and may visit the females periodically. The legend of wolverine unsociability may have to be rewritten.
In the West, dens are made very high in the mountains near treeline. Denning is probably the major risk to wolverines in the US, as mothers readily abandon dens at the slightest disturbance. Hence, we may need to limit snowmobiling and cross-country skiing to help preserve American wolverines.
I do not think logging has much of an effect on wolverines, since they live at such high elevations. It may even be beneficial if it increases the numbers of rodents, which they prey heavily on.
Wolverines are said to be scavengers, and there is something to this, but they are also omnivores who eat just about anything. The wolverine covers amazing distances in its never-ending search for feed. They are so ferocious that they have very few enemies.
There is a recorded instance of a wolverine stealing a mountain lion’s kill and then chasing the puma away. However, a black bear was recently recorded killing a wolverine in Yellowstone National Park. The intrepid and ferocious wolverine had tried to steal the bear’s elk kill right out from under the bear’s paws.
The wolverine is member of the weasel family, and it is best described as a weasel on steroids blown up to King Kong size. They have a reputation for ferocity and viciousness. This reputation is derived in part from the tales of fur trappers.
Wolverines were notorious for following fur trappers along their lines and destroying and eating any animals caught in traps. To trappers it often seemed that the wolverine was doing this out of pure spite. Wolverines also had a reputation for entering trapper’s cabins when trappers were away and destroying everything inside. To top it off, they would spray their foul scent from their glands all over the cabin.
A wolverine is hardly man’s best friend. Here a sweet, cuddly wolverine purrs and spreads the love around. Old-timers in the Truckee area, near where the photo was shot on February 28, say it takes only two swoops of those claws to kill a dog. The old-timers said that wolverines in that area “lived in holes”. I have seen the claws on a road-killed badger, though, and those were just amazing.
It is often said that wolverines love wilderness and refuse to have anything to do with humans. This is not necessarily true.
In northern Ontario, many sightings were made by trappers within 1/2 mile of Amerindian settlements.
In the Yukon, wolverines frequently raid garbage dumps on the outskirts of towns.
In Scandinavia, they prey quite heavily on sheep and reindeer, such that they are becoming a major predator problem. Further, they are recolonizing former territory that is now inhabited by humans, with homes, towns, roads, etc.
Wolverine fur is very valuable. It is the only fur that has the ability to withstand frost without freezing over. Hence it is often used to line the areas of parkas right around the mouth where the breath comes out. Otherwise, moist breath tends to cause frost buildup around the parka wearer’s mouth.
The low elevation record for a wolverine in California is an unbelievable 1,300 feet in Tulare County.
Conservation organizations have repeatedly petitioned the US Fish and Wildlife Service over the past decade to list the wolverine in the lower 48 as an endangered species. The petitions are constantly returned on a Catch-22 basis – the wolverine has to be studied, especially population dynamics, to determine if it qualifies as an endangered species, and it is so rare that it is almost impossible to study it.
Earlier, a wolverine petition was returned by the Bush Administration as invalid. After that, on March 11, 2008, the Bush Administration denied listing the wolverine in the Lower 48 on the basis that healthy populations in Canada and Alaska should be able to keep the wolverine from going extinct even if the wolverine is extirpated from the Lower 48.
In this, the Bush Administration took a new tack. Under Clinton and probably under all previous Presidents, a number of species were listed even though they had healthy populations in Alaska and Canada . After all, most of us live in the Lower 48, not Alaska, Canada or Mexico. And it seems odd to depend on the kindness of nations to the north and south of us to keep species from going extinct.
One problem of the lack of listing of wolverines is that wolverines can still be trapped. 8-18 are trapped every year in Montana, and biologists feel that none should be trapped anymore in the state. It appears that trapping in Montana is untenable based on new evidence.
A great wolverine article is here. It’s written by Physical Geography Professor Randall J. Schaetzl of Michigan State University. Among many other fascinating observations, he notes that the last Michigan wolverine was killed in 1860, not the early 1800’s. So the Ubly sighting was the first in about 150 years, not 200 years as most references state.
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