Black Bears Move Into the North Bay


On a gray early March morning in Sonoma County, everything is dripping. Somewhere, out of sight, in hollow trees and rocky caves, tiny American black bear cubs nurse in the dark. Born at less than a pound only a few weeks before, they won’t emerge until spring. But adults—ones that haven’t given birth this year—might be out and about, turning over logs, poking at anthills. In this temperate climate, coastal bears don’t hibernate like their high-country cousins. Food is plentiful all year round; there’s no need to sleep away the thin months. 

So even now, snow still deep in the Sierra, we are hoping to see one.

The road up the mountain at Sugarloaf Ridge State Park is washed out. Meghan Walla-Murphy, an ecologist and expert tracker, hops out of the ATV where the pavement ends and starts looking for evidence indecipherable to a novice. Signs might include bear scat laced with grass, saplings with the tops snapped off, trunks that have been used as back scratchers. They are hard to see: camera traps have captured hundreds of images, but park manager John Roney says there have only been five in-person sightings. Walla-Murphy inspects the post of a barbed wire fence. Nothing.

A little farther, a power pole tilts at a steep angle. Here, the wood is battered, marked by deep, horizontal gouges. “All of this is bear scratch marks, bear claws,” Walla-Murphy points out to me. Bites, too, she thinks. Brown hairs are stuck in the splinters. 

A decade ago, bears were a rare sighting in the North Bay. When a wildlife camera, newly installed near staff housing in the park, recorded one ambling by, it was thought to be a wide-ranging individual just passing through. Then, one August night in 2016, the camera caught not one, but three pairs of glowing eyes. Animals took shape—round ears; long, low back. Clearly, Ursus americanus. The mother bear neared, then veered off camera, closely followed by a second, much smaller, while the third, a lollygagger, stopped to inhale some scent in the dirt. The family indicated bears were not visiting but living in the park.

In response, the California Department of Fish and Wildlife (CDFW), state parks, winegrowers, ranchers, the California Indian Museum and Cultural Center, the Kashia Band of Pomo Indians, and others formed the North Bay Bear Collaborative to learn more about the newcomers and plan for their arrival. Walla-Murphy is the lead scientist.

A black bear (Ursus americanus) in Kings Canyon National Park, California. (Floris van Breugel via Nature Picture Library)

Throughout the Bay Area, black bear sightings are increasing. 

Last summer, a black bear stopped in the front yard of a San Rafael home, sniffing a garbage bag, raiding the strawberries. Another wandered a sidewalk in Larkspur. Three years ago, a black bear climbed an oak in San Anselmo, licking its paws and drawing a crowd in midday. 

It’s part of a trend all over the country: bears venturing into small towns and suburbs. They are hibernating under Connecticut decks and swimming in backyard pools in New Jersey. In one surreal occurrence, last year a black bear climbed a tree in Frontierland in Florida’s Disney World, a real wild animal exploring a fake version of the “Wild West.”

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In January, one found its way into Sallie Miller’s yard, tucked between the road to Sugarloaf Ridge and roaring Sonoma Creek, forested hills rising on either side. Returning home, Miller found her beehives smashed, wood frames scattered on the pavement. She’d seen scat on the lawn, but this raid was a different level of interaction.

“There were live bees everywhere,” she remembers. She and her husband cleaned up and went out, only to come back to find the bear had been back, making even more of a mess this time. “It was probably just hanging out on the hill, watching us,” she says.

Finally, they moved the remaining hives right by the house, thinking the bear wouldn’t venture so close. But they woke at 1:30 a.m. to find a bear in the carport. Banging pots and yelling got it to flee, and not long after, rains swelled the creek. “It hasn’t been back,” Miller says. But the trees on the other side of the water connect to 12,000 acres of public lands and large estates with few people: good bear country.


Much remains a mystery. What led to increased numbers? Maybe the bears are spreading from bear-rich counties like Mendocino as the overall bear population in California grows, up from between 10,000 and 15,000 in the early 1980s to roughly 65,400 today (though it is hard to compare precisely, as counting methods have changed). Maybe it’s a response to humans building deeper into wildlife habitat in the North Bay. Or it could be the recent catastrophic wildfires. Climate change alters the availability of food, from seeds to ants to trout, possibly pushing bears closer into the suburbs. 

Whatever the cause, how will this influx of large omnivores affect the ecosystem of the North Bay?

“Black bears are common and well-studied everywhere and we still know so little about them,” says John Roney, park manager at Sugarloaf Ridge.

In an effort to answer some of these questions, starting this summer CDFW will satellite-collar bears in Marin, Sonoma, Napa, and Solano counties, aiming for eight males and eight females. Biologists will document where the bears are roaming, where they are crossing roads that might put them in danger, the location of den sites. Then, by placing cameras on dens, they will estimate numbers of cubs. 

“It just seems like it’s a good time to study this species,” says Stacy Martinelli, the environmental scientist for CDFW running the satellite collar study. “It’s such a big, charismatic, wonderful animal.” As they move south, though, toward the San Francisco Bay, the bears will eventually run out of forest and, increasingly, into people. “The more that we’re in their space, there’s an increased likelihood that we’re going to encounter them,” Martinelli says. More knowledge may keep trouble at bay; if the state knows the bears’ travel routes, for instance, it can work with landowners and Caltrans to develop wildlife corridors. 

In addition, ongoing DNA studies by the North Bay Bear Collaborative, where volunteers collect scat and send it to a lab at UC Davis for analysis, will suggest numbers of individual bears, genetic relationships between them, and where they are coming from. Estimates based on these studies put about 70 individual black bears in Napa and Sonoma counties, with two or three in Sugarloaf Ridge State Park. Marin County results will be available later this summer.

One clue to how the black bear might fare in the region comes from the past. The Bay Area used to be teeming with bears, but most weren’t black bears. They were California grizzlies. Reports have them running down a hill on the Peninsula, pacing near Strawberry Creek in what would become Berkeley, leaving tracks at Mount Diablo. Nineteenth-century zoologist C. Hart Merriam divided the California Grizzly into seven subspecies, three of which met at San Francisco Bay: the California Coast Grizzly, the Tejon Grizzly, the Klamath Grizzly. (Now all grizzlies are thought to be the same subspecies of brown bear: Ursus arctos horribilis.) The final wild California grizzly was seen 100 years ago, in 1924, by a cattle rancher near Sequoia National Park. “It was the biggest thing I ever saw—bigger than any cow, and looked as though sprinkled all over with snow,” claimed Alfred Hengst. Black bears, who never lived in this area historically in any abundance, are just walking in their mighty footsteps.

While grizzlies still roamed the state, most black bears near San Francisco were likely captives. An ad in the San Francisco Examiner in 1888 read, “Wanted—A BLACK BEAR CUB, NOT more than one year old; must have fine coat and be gentle.” An Oakland Post Enquirer article from 1928 announced “Rampaging Bear Gets New Owner” and told the story of 5-month-old Betty, “probably the only bear in Berkeley that is not a football player,” who escaped. She knocked over a bunch of trash cans and was then adopted by the police officer who tracked her down.

Black bears are smaller and shyer than grizzlies. They love the forest while grizzlies prefer open meadows and chaparral but, in ways, they play a similar ecological role.

Omnivores, black bears eat voraciously and expansively, everything from cow parsnip roots to yellow jackets to clover. In Florida, bold ones go after alligator eggs. In California vineyards, refined ones graze on pricey grapes. Though they don’t often hunt large animals, they will take available meat. One wildlife camera at Sugarloaf, trained on a dead deer, caught a bear swiping it like it was shoplifting jeans at the Gap and then disappearing into the woods. And, if they can find them, they dine on half-eaten peanut butter sandwiches, granola bar crumbs, cold French fries. 

In this, they are like the grizzly, of whom John Muir commented, “To him, almost everything is food except granite.”

Bears are fierce and curious, clumsy yet graceful. (Some words just seem made for bear movement—“amble,” “lumber.”) With a roughly human shape and larger-than- human size, they inspire affection and fear. As a result, bears are embraced symbolically (see: teddy bears) but often are not tolerated in actuality (see: the extinction of the California grizzly). Grizzly Peak Boulevard, Bear Valley in Marin, Grizzly Island in Suisun Bay—bears’ power lingers in names and pictures even when the animals are absent. Nowhere is this clearer than on the UC Berkeley campus. Here bears are everywhere: bear statues, bears on T-shirts, bears on notebooks. The California state flag, with its big grizzly, flies over it all. 

Left to right: A good example of a black bear’s right front paw track (omarfpena via iNaturalist, CC-BY-NC); black bears claw at tree trunks, sometimes scraping away the bark (Kyle C. Elshoff via iNaturalist, CC-BY-NC); piles of their sometimes-tubular shaped scat changes in appearance with the bear’s recent meal. (nescaladahsu via iNaturalist, CC-BY-NC)

The Bay Area has seen a wave of new and returning species in addition to bear in recent years: osprey, peregrine falcons, gray fox, coyotes.  Though we might not know the exact reasons, the influx is no mystery at all, according to Christopher Schell, a UC Berkeley ecologist who studies urban carnivores.

“Most cities, like this one, are situated on purpose on top of biodiversity hotspots,” Schell says. As if to underscore his point, a hummingbird darts outside the second-story window of his office, between a eucalyptus grove and redwoods along the creek. Animals of all kinds are attracted to spots with plentiful water, fertile soil. “We need the same types of resources that many of these other species need.”

And when carnivores come in, they change the landscape around them. This effect is called the “landscape of fear.”

“Having bears or pumas or wolves on the landscape dictates where deer go,” Schell says. For example, one study showed that west of the Sierra Crest, where large populations of black bear prey on mule deer fawns, fewer deer migrate to that bear-dense summer range. Deterred from the west side, many feed on the east side instead. Changes in deer behavior like this have far-reaching results. “They’re not going to overgraze on native plants and vegetation. And if they don’t do that, then the native plants and vegetation can sustain a greater diversity of birds, which can then eat and sustain a greater diversity of invertebrates.” 

A broad diet and wandering ways make black bears and grizzlies important seed dispersers, often in cooperation with other species. One study in the Carson Range of Nevada showed that deer mice nabbed chokecherry, Sierra coffeeberry, and red osier dogwood seeds from black bear scat and buried them. The ones they forgot to retrieve, germinated. Bears also enrich the soil; both species haul migrating salmon out of the rivers and drag them into the woods or eat them on the bank, then ramble away to defecate, spreading marine nutrients and fertilizer into the forest.

Carnivores change the spaces where they live and, in turn, these spaces alter carnivores, particularly those lured by garbage. “Eating more anthropogenic foods changes stress physiology, gut microbiome, how bold the animal is,” Schell says. Black bears with easy access to trash grow bigger and have more cubs. Paradoxically, though, these garbage-filled areas can be “sinks.” They draw bears with the temptation of easy calories, but car crashes and conflict with humans (which can result in removal or killing) keep numbers low.

Humans are part of the ecosystem incoming black bears will have to navigate. And perhaps our most dramatic effect on animal lives comes through the stories we tell. Newspaper accounts and memoirs portrayed California grizzlies as ferocious man-eaters and sheep stealers, but a recent study by UC Santa Barbara professor Peter Alagona analyzed teeth and bones to show that, like black bears, grizzlies ate mostly plants. The arrival of the Spanish and their livestock in 1542 prompted a change in diet, though only from 10 percent meat to up to 26 percent. But the lore of huge, bloodthirsty predators and the glory of besting such a monstrous creature provided fuel for killing them off.

An actual bear roaming the Berkeley campus, sizing up the statuary, seems a long way from likely. The East Bay and South Bay don’t have breeding populations, according to John Krause, senior environmental scientist supervisor with CDFW, though the most recent draft of the state’s Black Bear Conservation Plan shows suitable bear habitat in the Santa Cruz Mountains and the Diablo Range. But even bears several valleys over pose interesting questions about the nature of nature, Schell says. “It would restart this conversation around why we think we’re separate from it when we live in the city.” 

One of the most important goals of the North Bay Bear Collaborative, according to Walla-Murphy, is rebuilding a “bear culture,” reframing our stories and expectations: “We don’t remember how to live with these critters anymore.” Rectifying this involves learning from local tribes and other communities that have coexisted with bears for a long time, she says. 

Over the past three years, as part of an effort to pass on knowledge about black bears to its youth, the Kashia Band of Pomo Indians has conducted a monitoring program on the Kashia Coastal Reserve and the Stewarts Point Rancheria. Interns complete vegetation transects, install wildlife cameras, and collect seeds for habitat restoration projects. In addition, according to Nina Hapner, director of environmental planning for the Kashia Band, they learn about black bear habits and habitat, needs, and importance in the system. The interns also interview family members or other tribal members about the tribe’s bear history and understanding.

The interns didn’t glimpse a bear until the third year, recalls Hapner, but when they did, it made an impression: “Everybody knew that we have bears up on the Kashia Coastal Reserve … but we just hadn’t seen one. And then we see this guy lumbering along, and it was like: Yes!”

Observations like these mean they are not only learning about bears but from them. “Basically, what a bear eats, we can eat,” Hapner said. “Fish, berries, some plants when they’re young. They teach us things if you watch, if you pay attention.” She adds, “Just opening your eyes and being open to that instead of being fearful … That’s really important.”

After the bear ransacked Miller’s beehives, Walla-Murphy and Roney stopped by and advised her on how to avoid another visit. Electric fencing would keep the hives safe, as would, possibly, planting species bears love, like manzanita, on the far side of the creek. If bears show up again, banging pots and pans should scare them away. Roney sent her an air horn. In general, those living in bear country should protect their trash and compost, bring in bird feeders, keep pets inside, pick up windfall from fruit trees. Anything smelly should be secured. The most important thing is to establish a boundary and defend it, says Walla-Murphy: “The bears will respect the boundaries if we have the boundaries, but if we don’t, they’re going to push back.”


Back at Sugarloaf Ridge, we begin to walk toward the old ranch where the first bear was caught on camera. Walla-Murphy strides through the grass, eyes to the ground, pointing out the swirl of a bear track, clipped stalks where a bear could have grazed. She scrambles up a hillside to see whether a bear might have taken this route to the abandoned orchard. Wildfires in 2017 and 2020 burned much of the park and all the old ranch buildings used as staff housing. This left a fence that no longer fences anything in or out. A power line without electricity. A mailbox on a pole that gets no letters.  With a few trees left in the orchard—apple, pear, persimmon—it’s a wildlife playground now. 

In a clearing where the buildings used to be, bright yellow daffodils mark gardens of previous inhabitants. A huge live oak stands, half burned and flourishing. We continue up the trail, ducking under and scrambling over trees downed in the recent atmospheric river that swept up the coast. Finally, Walla-Murphy comes upon a bear bed, a divot under a scorched conifer. Bears love the bases of big trees like this, the options of advancing down the hill, of retreating up the trunk. She’s never seen a bear in this park, but evidence is all around. And this morning, filled with reedy birdsong and the rushing water of Bear Creek, after an absence of a century, bears are once again possible.

Support for this article was provided by the March Conservation Fund.


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