With its enchanting eyes, powerful jaws, acute senses and haunting howls, the gray wolf (Canis lupus) — the largest member of the dog family — is a wilderness icon. Once the most widespread mammal on the planet, gray wolves roamed across large swaths of North America, Europe and Asia.
However, as human settlements grew, these livestock-killing canids became “vermin” and were hunted to near-extinction in many parts of their range. By the mid-20th century, wolves were extirpated from the contiguous U.S.
Their remarkable comeback since the 1980s, thanks in part to their reintroduction to Yellowstone National Park, has sparked joy, controversy and conflicts.
The latest saga is playing out in California, where there’s a lot of potential for conflict: It’s the most populous U.S. state with nearly 40 million people. Some 7 million cattle graze on 57 million acres of rangeland, half of which are privately owned.
California’s wolves, which naturally dispersed south from Oregon, are now further expanding their territories, with more frequent encounters — and conflict — with humans . “Almost every pack does overlap to some degree with an agricultural area with livestock,” said Axel Hunnicutt, a biologist who coordinates the wolf program for the California Department of Fish and Wildlife (CDFW). Almost every group has killed livestock. “That’s one thing that unites all of the packs in California, unfortunately,” he added.
While conservationists hail the wolves’ return, ranchers are already losing livestock. Some residents, unaccustomed to living with the canids for nearly a century, worry about their safety.
How wolves will change the ecosystem, where they’ll settle, how well they’ll survive and how they’ll coexist with people remains to be seen. “We’re at the beginning of this really exciting recovery … so there’s a lot of unknowns,” said Kaggie Orrick , director of the California Wolf Project at the University of California, Berkeley.
What we do know is that there are now 50-70 wolves living in 10 packs in various parts of the state, according to CDFW. Their numbers are steadily increasing, and they are protected under both California law and the federal Endangered Species Act. They can’t be hunted or removed, even if they kill livestock.
As the wolves navigate a complex mosaic of ranches and farms, wild lands, highways and wilderness corridors, slowly recolonizing the landscape, the state’s wildlife agency faces challenges. Protecting carnivores is never easy, but especially amidst concerns about the new wild canids in people’s backyards and on their rangelands.
That proximity has made some ranchers and members of the public antsy, at best.
A brief history of California’s wolves
California is historically wolf country, with anecdotal evidence of their presence dating back to the 1700s. The state’s last gray wolf was killed in 1924, trapped and shot in Lassen county.
But on a relatively warm December day in 2011, a radio-collared young male named OR-7 strayed south into California’s southern Cascades from Oregon. Researchers tracked his remarkable 1,600-kilometer (1,000-mile) journey. He was the first wolf known to set foot in the state after an 87-year absence. But he returned to Oregon and founded the Rogue Pack. His descendants subsequently crossed the border and established packs in California.
As social animals, wolves form dynamic groups, sometimes hanging around for a bit and then moving to another area. They only become an established pack, in the eyes of the state wildlife agency, when a member has pups or they’re seen in the area at least four times within a six-month period.
The Shasta Pack, with two adults and five pups, became the state’s first official pack in 2015, moving into Siskiyou county near the Oregon line. But the pack quickly disintegrated, and by 2016, most members were presumed dead. That same year, another group, the Lassen Pack, appeared on the edge of Lassen and Plumas counties, and two adults successfully raised litters. In subsequent years, others have popped up, and today, 50-70 individuals live in at least 10 packs. Three new packs were confirmed in early 2025.
“Most of the wolf presence is concentrated in northeastern California, north of Lake Tahoe and east of Interstate 5,” Hunnicutt said. Another pack, the Yowlumni Pack, named by the Tule River Tribe, settled in the southern Sierra Nevada. It roams more than 320 km (200 mi) from the nearest known northern California pack — a testament to how far wolves can disperse in the landscape. “Our projections tell us there is more habitat that wolves can occupy in the future, depending on native prey availability like deer and elk,” said Matthew Hyde, a carnivore ecologist at UC Berkeley’s California Wolf Project.
Wolves are resilient. “[They] are one of the most widespread, generalist and adaptive species on the planet and can basically be anywhere,” Hyde said. Human tolerance to their presence, he added, determines whether wolves can live in a place.
They reproduce rapidly, with an average litter size of 4-5 pups each year. Between December and February, they begin seeking out mates, and by April, they’re denning with pups. However, despite their large litters, many of those pups don’t survive their first year.
That large litter size, coupled with the fact that California-born wolves are mating with others from outside the area and forming new packs, Hyde said, is “why we’re starting to see that exponential growth that’s happening in California.”
The Whaleback Pack in eastern Siskiyou county, one of the most well-known, has been prolific. It produced seven pups in 2021, eight pups in 2022, eight more the next year and at least six pups in 2024. Those eight-pup litters are the largest known in the state in more than a century.
With prey-rich potential wolf habitats state-wide and a rapid reproduction rate, scientists expect wolves to further expand and will likely become a constant presence in California’s landscape.
Apex predators in the ecosystem
Wolves are apex predators that serve a critical role in the system. They keep fast-producing animals like deer and elk in check. Studies have revealed how this helps reduce deer-vehicle collisions and prevent transmission of chronic wasting disease and other contagious diseases by targeting sick and weak animals.
“We do, in theory, know that they could regulate deer populations,” Orrick said. “They could influence scavenger communities. They could alter prey behavior, as we’ve seen in other systems.”
While the transformation attributed to wolf reintroduction in Yellowstone National Park has been challenged in recent years, there’s no denying that a new predator in an ecosystem has cascading impacts.
However, California is very different from other parts of the U.S., and the wolves’ effects here will unfold over the next few years. “This landscape is fragmented and human-dominated, so the outcomes might look very different [from Yellowstone],” she said. “We’re still very much in the early stages of understanding how wolves shape ecosystems, specifically in a state like California.”
The California Wolf Project, in collaboration with CDFW, has installed a network of camera traps across the northern part of the state to track the wolves’ ecological impacts on the landscape. Researchers are also studying their diet, their interactions with mountain lions (Puma concolor), black bears (Ursus americanus) and other predators, and observing how drought and wildfire affect them.
These wolves have settled in environments ranging from remote mountain wilderness to working lands with close proximity to people. They have larger territories than their brethren living elsewhere in the U.S.
Although the packs are concentrated in the northeast, they are not bunched closely together and conflicts between them are few. Hunnicutt has two theories why. One possibility is that these wolves are just beginning to establish their home turf. Another factor, he said, is that “they’re made up of animals that know each other.” The relative peace will change over time as social dynamics develop.
California’s wolf management program
OR-7’s brief stay in California in 2011 prompted discussions between CDFW, conservation groups, livestock producers, concerned citizens and other stakeholders. Soon, the agency began work on a conservation plan for gray wolves that it finalized in 2016. It outlines wolf recovery in three phases, and is based on the number of breeding pairs in the state. A pair is defined as at least one adult female and one adult male that have produced a minimum of two pups that survived their first year.
With at least four breeding pairs documented in 2023 and 2024, California’s wolf conservation plan is now in Phase 2. This provides some flexibility in managing conflicts, given that livestock kills have increased. In the last decade, the state has investigated 274 cases of possible wolf attacks on livestock; 128 were confirmed. For context, this amounts to about one per month.
The Whaleback Pack in east Siskiyou county stands out with 77 confirmed attacks. Hunnicutt attributed the pack’s preference for livestock to culture — behavior that is passed down from parents to pups. “It’s clear that with certain packs, there is chronic depredation, and it has become a behavioral situation,” he said. But in some situation, he added, it simply comes down to survival: the lack of other prey.
CDFW launched a three-pronged program in 2021 to pay ranchers for livestock that was killed by wolves and also compensated them for indirect losses such as lower pregnancy rates and decreased weight of animals in their herds. The program also paid for nonlethal deterrents and warning systems. The pilot program ended in 2024 as the $3 million funding ran out, so CDFW currently compensates only for direct losses from wolf attacks.
In June 2025, CDFW launched a pilot program to mitigate conflict in Siskiyou county and the Sierra Valley, where livestock depredation is relatively high. Staff are outfitting some wolves with GPS collars that allow them to track the canids’ movements.
So far, they have collared 12 wolves in three packs. With real-time information, officers can harness wolves’ fear of people to drive them away from towns or ranches, or use hazing techniques, such as rubber bullets and beanbag shells, to deter them when necessary. Only CDFW officials are permitted to use these tools.
Hunnicutt said going into Phase 2 also means CDFW is now initiating a review of the gray wolf’s endangered status, given its increase in numbers. The next phase of the recovery program kicks in when eight breeding pairs are in a region for two consecutive years. It may involve delisting of wolves from the Endangered Species Act or their lethal removal in the case of conflicts.
Hyde, the biologist at UC Berkeley’s wolf project, called this reassessment a “welcome process” as it updates the current management plan with more science and community perspectives. “An important piece of wolf conservation and management is mitigating impacts with human communities, and Phase 2 may allow for greater flexibility to have successful conflict mitigation,” he said.
An unknown future with a recolonizing predator
For nearly a century, the wolves’ howls fell silent in California, but that’s changing. As wolves continue to thrive, their future depends on the protections that California and Washington, D.C., decide to provide. With the fate of public lands potentially in jeopardy under the Trump administration, wildlife, including wolves and their prey, may have less protected land to roam, which might bring about more human-wolf and wolf-livestock conflicts.
“Hearing a wolf howl in California landscapes after 100 years is super great,” Hyde said. To make it last, he emphasized the importance of people working together to mitigate livestock kills and conflicts with people. This, he said, will “be the ultimate determinant in how wolves are going to be able to spread.”
While concerned ranchers are counting their losses, some members of the public are anxious about safety. A handful of California counties have issued public safety emergencies following wolf attacks on livestock, though no humans have been harmed.
“We’re not seeing wolves that are acting aggressively,” Hunnicutt said. “Wolves, compared to the other large carnivores in the state, are definitely low on the list in terms of likelihood of actually posing a public safety threat.”
Numbers back that up: According to a report by the Norwegian Institute for Nature Research, only two fatal attacks were attributed to these canids from 2002-20 in North America. The authors note that with 60,000 wolves in North America and 15,000 in Europe cohabiting with hundreds of millions of people, “the risks associated with a wolf attack are above zero, but far too low to calculate.” In contrast, dogs kill more than 40 people each year in the U.S. alone, while cattle kill 20-22 Americans yearly.
People’s internal fear of wolves may be a substantial factor in considering wolves a public safety threat. “We have an instinctive fear of wolves in our own unique history,” Hunnicutt said. “When you suddenly do have a wolf reappear into your life … it is very scary for people.”
Some of the public’s fear of these canids, he said, comes from the visual goriness of a wolf hunt and their pack hunting style, which some perceive as more threatening than bears and mountain lions that hunt alone.
As wolves begin their recolonization in California, sharing the land with predators requires co-existence. But to some, wolves are still varmints. “Public tolerance, in areas where wolves are, is decreasing,” Hunnicutt said, adding that the wolves’ future remains precarious. “We were very good at eradicating the species 100 years ago. … It wouldn’t take very much for the population to crash, should bad actors decide to take action.”
Citations:
Raynor, J. L., Grainger, C. A., & Parker, D. P. (2021). Wolves make roadways safer, generating large economic returns to predator conservation. Proceedings of the National Academy of Sciences, 118(22). doi:10.1073/pnas.2023251118
Byard, R. W. (2024). Death and injuries caused by cattle: A forensic overview. Forensic Science Medicine and Pathology. doi: 10.1007/s12024-024-00786-8
This article originally appeared on Mongabay.
