State of snowmobile access: Stanislaus lawsuit grows, Lassen releases plans as other Districts stall

Hunter Schmikey in Truckee | Travis Alley

Eighteen months after its decision to update over-the-snow vehicle (OSV) policy in Stanislaus National Forest, the legal battle between the U.S. Forest Service, snowmobilers and environmental advocates is only just beginning.

Now the Forest Service finds itself challenged on two fronts as WildEarth Guardians have joined the fight, alleging Stanislaus’s 2021 decision did not do enough to protect endangered animals. The Forest Service was already defending itself against Sierra Snowmobile Foundation and others in a lawsuit claiming Forest Supervisor Jason Kuiken went too far when he approved a 67 percent reduction in OSV access last year.

“We intervened on the side of the Forest Service, but also independently brought claims against the Forest Service,” says WildEarth Guardians public lands attorney Chris Krupp. “We think the snowmobiling groups’ claims are unfounded. But at the same time, we think the Forest Service didn’t do enough to analyze winter travel in Stanislaus, particularly in regards to winter wildlife. We are asking the court to keep the travel plan in place but direct the Forest Service to reconsider protections for endangered species.”

Stanislaus National Forest was the first forest in the Tahoe Sierra, and one of the first in the nation, to update its OSV policy as required by a 2013 federal court ruling. Now only 13 percent (119,104 of the District’s 898,099 total acres) remain open to snowmobiling and other motorized winter sports. The policy closed all terrain below 5,000 feet and imposed 12- to 24-inch snowpack minimums depending on location. The new rules took effect last winter.

50 years in the making
Stanislaus’ OSV maps are a court-ordered attempt at diplomacy between various public interest groups including snowmobilers; nonmotorized, backcountry travelers such as skiers, splitboarders and snowshoers; private landowners; environmental scientists and stewards; and more than a dozen government agencies. It is part of an ongoing process that began when a 1972 executive order required federal land-management agencies to minimize environmental impacts and conflicts associated with the use of motorized off-road vehicles on federal public lands.

While requirements were completed in the forests of Tahoe Sierra for dirt bikes, quads and other vehicles by 2010, that same analysis for winter machines was not performed. Three groups – Snowlands Network, Winter Wildlands Alliance and the Center for Biological Diversity – subsequently sued the Forest Service in 2011 to perform that study. The result was a 2013 settlement to complete the analyses. Each National Forest that sees significant OSV use is now required by the National Environmental Policy Act to assess potential environmental impact and release updated maps on where OSVs, including snowmobiles, snowbikes and utility terrain vehicles, may be used.

“We intervened on the side of the Forest Service, but also independently brought claims against the Forest Service. We think the snowmobiling groups’ claims are unfounded. But at the same time, we think the Forest Service didn’t do enough to analyze winter travel in Stanislaus …”     – Chris Krupp, WildEarth Guardians

Since 2017, Tahoe Weekly has reported on this process for the six Forest Service districts that encompass the Tahoe Sierra — Eldorado, Humboldt-Toiyabe, Plumas, Tahoe, Stanislaus and the Lake Tahoe Basin Management Unit, as well as Lassen National Forest, which is a frequent destination for Tahoe locals and visitors. Follow our complete coverage at

What does the fox say?
The newest group to join the legal debate, WildEarth Guardians, is a nonprofit grassroots environmental organization headquartered in Santa Fe, N.M., whose mission is to “protect and restore the wildlife, wild places, wild rivers and the health of the American West.”

Founded by a joining of several environmental groups in 2007, they’ve since worked to stop illegal grazing, halt fracking and coal mining, protect more than 21 million acres of forest in the Southwest and push for endangered protections for hundreds of species.

Its lawyers assert the Stanislaus plan did not adequately analyze the effects to four species of endangered or threatened wildlife: the Sierra Nevada red fox, Pacific marten, Sierra Nevada yellow-legged frog and Yosemite toad.

Court filings cite a distinct population segment of Sierra Nevada red foxes known to live at Sonora Pass. Once thought to be extinct, the foxes were rediscovered in 2010. According to U.S. Fish and Wildlife Service, while they previously ranged throughout the Sierra Nevada, there are now estimated to be less than 50 individual foxes in this region. This sub-species was granted federal endangered status in 2021, only three weeks after the Stanislaus OSV plan was released.

“This species is on the brink of extinction and impacts to individual members risk extirpation of the entire population,” states WildEarth Guardians’ court motion. “The best available science thus supports a full closure of the Sonora Pass OSV play area to adequately protect the fox during its entire critically important breeding season.”

Under the new policy, OSV access at Sonora Pass has been limited to a relatively small area that now closes after April 15 each year.

Benjamin Sacks, director of Mammalian Ecology and Conservation Unit at University of California, Davis, an expert on Sierra Nevada red foxes has been studying the mammal since 2010. He says that dens are chosen in December with pups born between March and May and that OSV use throughout winter can impact the pups’ chances of survival by compacting the dens and allowing their main competitor, coyotes, easier access to the high country.

“Any activity in this area after February risks impacts to Sierra Nevada red fox reproduction,” Sacks wrote in his 2018 public comments to the Forest Service. “Our preliminary data suggests that coyotes actively used groomed or well-used OSV trails to access higher-elevation locations they might otherwise have been unable to access under those high snow conditions. Studies in the Rocky Mountains also suggest that snowmobile trails increase coyote access.”

However, available studies on the impact of snowmobiles on wildlife are less than conclusive.

A 2016 study published in the Journal of Wildlife Management showed “the overall influence of snowmobile trails on coyote movements and foraging success during winter appeared to be minimal.”

“I think it’s a philosophical question,” says David Page, executive director of Winter Wildlands Alliance. “These impacts are expensive and hard to prove. So, do we take action before we know or wait until a species is extirpated before we take action? Do we sit back and say we can’t prove it, so let’s not do anything differently? And then they’re gone.”

Both snowmobilers and wildlife advocates have pointed to inconsistencies in the Stanislaus plan. For example, while it requires 24-inch snowpack minimums in some wetland areas suitable for the endangered Yosemite toad and Sierra Nevada yellow-legged frog such as Stanislaus Meadow and Highland Lands, it only calls for 12 inches at others such as Summit Lake, Niagara Creek, Herring Creek, Tryon Meadow and Bear Tree Meadow.

Snowmobilers dispute Stanislaus plan
In their suit, snowmobilers claim Stanislaus’ new restrictions on OSV access to be arbitrary and capricious and that environmental studies have demonstrated no measurable effects of OSVs on the environment or wildlife.

“The decision will prevent me and numerous other SSF members from riding snowmobiles in areas of the Stanislaus National Forest we have historically accessed and visited,” wrote Sierra Snowmobile Foundation land use director Kevin Bazar in a court declaration. “Nor will I be able to legally access areas outside of the small, designated area on Sonora pass, which are all popular snowmobile areas. I will also no longer be able to access via snowmobile Lookout Peak between Pacific Valley and Highland Lakes Road. I will also potentially be subject to citation for traveling on ice-packed roads if the snow depth is less than 12 inches, even if there is no contact with the surface. These are all actual and imminent injuries to me.”

The case is working its way through the U.S. District Court for the Eastern District of California.

“We’re approaching the time where it will go before the judge who will review the administrative record and evaluate whether Forest Service made a reasonable determination,” says Krupp.

Lack of signage
Meanwhile, the new policy has been in effect since last winter with paper maps and QR codes for digital maps available at Forest Service stations.

“We’re going through maps like they’re going out of style,” says Stanislaus spokesperson Benjamin Cossell. “Our message is to have that info before you load up your OSV and head to the sno-park. Last year, we weren’t in a ticket-issuing mode. It was more about educating people on the rules and boundaries and helping them make the right choices and be on the right path. I feel like the word is being heard that people need to have a better understanding of where they should and should not be.”

While maps are crucial, others argue a current lack of signage in the forest itself makes it difficult for users to stay in approved areas, especially when the boundaries don’t follow natural terrain features, as is the case with Pacific Valley. Stanislaus National Forest was able to install some temporary signage along trails last year and hopes to install more permanent signage this year, says Cossell.

Follow our coverage on OSV access at

The forest’s general counsel and Sierra Snowmobile Foundation both declined to comment on the pending litigation.

Lassen releases new OSV maps
Lassen National Forest became the second forest in the region to update its OSV policy when forest supervisor Deb Bumpus released her final decision on July 19, 2022. The selected alternative allocates 747,192 acres as open to OSV use, which represents 65 percent of the total forest. This is a 216,838 acre, or 22 percent, decrease from previous access.

Twelve-inch snow-pack minimums off trail and 6 inches on groomed trails are now required. While OSV use along the Pacific Crest Trail is prohibited by the National Trails System Act, 12 crossing points are designated. The plan outlines six specific OSV use areas including Ashpan, Bogard, Fredonyer, Jonesville, Morgan Summit and Swain Mountain.

The new policy is in effect for this winter. Lassen National Forest did not respond to request for comment on the plan.

Other District plans’ status
According to Forest officials, Eldorado and Tahoe National forests expect a decision on their plans sometime this year with implementation for winter 2023-24. Plumas National Forest is aiming for a decision by the end of 2024, pointing to recent wildfires as the reason OSV policy changes have taken a back seat.

“While we didn’t have big wildfires this season, the forest priority right now is community protection, reducing fuel around communities to reduce the risk,” says Plumas public affairs officer Tamara Schmidt. “There is also repair and restoration work tied to those fires.”

The 6.3-million-acre Humboldt-Toiyabe National Forest, the largest in the lower 48, has yet to commence its OSV policy analysis.

Lake Tahoe Basin Management Unit hopes to release a draft environmental assessment with possible alternatives by late 2023. There will be another period of public comment at that time.

“For almost each letter received by the Forest Service supporting one approach, there were also comments supporting the alternate viewpoint to the issues raised,” states a Dec. 20, 2022, Forest Service press release. “The Forest Service will be developing alternatives that include balanced approaches. Alternatives that globally favor one user group over another are not being considered. This will ensure that any alternative available for the Forest Supervisor to choose from could be truly implementable, provides high quality opportunities for all members of the public, and conserves natural resources.”

Of course, things could always get pushed back again. After all, many of these forest releases said the same thing last year.

“We’re waiting like everyone else,” says Page. “I think as a community everyone is frustrated it is taking as long as it has. But the agencies are underfunded. They have other priorities they are trying to deal with. All these forests were sort of the guinea pigs.”


Eldorado | Decision expected in 2023 |

Humboldt-Toiyabe | Not yet begun analysis |

LTBMU | Draft environmental assessment expected late 2023 |

Lassen | OSV plan in effect (released 2022) |

Plumas | Decision expected late 2024 |

Stanislaus | OSV plan in effect (released 2021) |

Tahoe | Decision expected in 2023 |