A regular swim near the Albany Bulb turned terrifying over Labor Day weekend when a small group of swimmers were bothered by a persistent sea lion as they rushed to get back to land.
“I call it an attack. We were not bitten, but it felt like an attack,” said Teri Hudson, one of three swimmers hassled by the sea lion the morning of Sept. 5, while on their routine plunge from Albany Beach into San Francisco Bay.
“This was definitely a targeted interaction,” said Hudson, an Oakland teacher who lives in Albany. “It didn’t feel safe or friendly.”
Hudson, a member of an East Bay open water swim group called the Blue Boobies that use Albany Beach as a base, was on high sea lion alert that day.
Swimmers from the group saw around three dead or seemingly ill sea lions (including one fur seal, a type of sea lion) on or near the beach in the days before and after the incident. They believe the animals were sickened by domoic acid toxicity, a neurological or brain poisoning affecting California sea lions at record rates over recent years. Many experts link the increase to the warmer waters of climate change.
The dead sea lions are gone now, and there haven’t been any more recent sightings at least by the Boobies, including of the sea lion that chased them in the surf.
The Marine Mammal Center has seen a spike in domoic acid poisoning in sea lions and fur seals over the past several months – news the swimmers were following closely. Cases are concentrated on the Monterey Peninsula, but also found along the California coastline, including in the San Francisco Bay. “Since 1998, when we diagnosed the first case in marine mammals, this brutal disease has become much more unpredictable and intense,” the center said in a recent web update.
There’s no way to know if the Albany sea lions were affected by domoic acid, without testing. But beached sea lions are rare along the East Bay shoreline, so any at Albany Beach is a twist from the norm.
“I’ve been swimming consistently for about seven years from the [Albany] Bulb. And this is the first year that we’ve seen sea lions showing up at all, and they’re all sick,” said Colleen Haraden, a founder of the Blue Boobies.
Attacks in the San Francisco Bay are extremely uncommon, though still fresh for some people, is the unusual cluster of four sea lion attacks — with bites — in San Francisco’s Aquatic Park cove in 2017 and 2018. Domoic acid toxicity was among the theories considered to explain the animal’s aggressive behavior, along with food shortages. But nothing was proven.
Haraden, who lives in Richmond and works in Berkeley in water clean-up and restoration, said she was first surprised when she saw two sea lions off the Albany shoreline in June. Then came Labor Day.
In a cluster of days around Labor Day weekend, Boobie swimmers said they saw one dead sea lion in the waters off Albany Bulb, and one on the beach. A fur seal, a type of sea lion, also died on the beach that weekend, they said. (A sea lion was also sighted by a photographer on the shoreline of the Berkeley Marina on Sept. 10.)
The animal that scared the swimmers in the water a little after 8 a.m. on Sept. 5 was almost certainly the same sea lion they’d seen lethargically planted on the beach since the day before, seemingly out-of-it and blinking into space, Hudson said.
“We assumed he was sick,” Hudson said. (The Boobies assume the sea lion was male, as females tend to favor southern water breeding grounds in the summer, but they weren’t sure.)
“It’s been really upsetting to all of us, it’s a very peaceful, wonderful place that many of us have been enjoying for years,” said Hailey Hibler, another Blue Boobie swimmer. “We worry about what will happen in the future if waters continue to warm.”
Blondie was basking on the beach when they entered the water
Naming him Blondie, for his traditional honey fur, Hudson said some of the dozen or so swimmers that morning observed the critter for a while before deciding it was safe to hit the water. Someone had put yellow caution tape around Blondie, presumably to keep people and their dogs away, she said.
“We went straight down to the water, and hung out for a little bit to watch him to see what he’d do. He didn’t seem interested,” Hudson said. “He really didn’t do anything. He tended not to pay attention to us.”
But soon that changed.
After stroking for about a half mile through the surf west to their usual turnaround point, one swimmer glanced back at the beach, and noticed, surprised, that Blondie had moved further south down the beach.
He wasn’t as immobile as it had seemed.
They quickly strategized, Hudson said, deciding to swim back closer to the rocky northern shore than their usual route.
“About three to five minutes after we’d turned, Sarah started screaming, ‘I see the sea lion,’ ” Hudson said, referring to one of her swimmates. “We assumed it was the same one; he was gone from the beach.”
It happened fast, she said. The sea lion was near them, with them. Her memory is blurred.
“Adrenaline clicked on. I can’t quite remember. I don’t know if I got bumped. We were reacting,” Hudson said. “At some point he swam right towards me and I put my hand out and pushed his head away.”
He dived. He surfaced. He seemed in pursuit, she said. They used their swimming buoys as shields.
“He was swimming under us, over us. At one point I turned on my back and kicked at him with my fins.”
They got close enough to the rocky northern wall of the beach area to hoist themselves up, hearts beating fast.
“We were recovering and I heard a scream,” Hudson said.
The third swimmer in the group, who Hudson did not want to identify to protect her privacy, was about 100 years offshore, with the sea lion. And she was terrified.
Hudson saw the sea lion circling her body. The swimmer told her afterward that it felt like the sea lion was “wrapping himself around me.”
“She completely panicked,” Hudson said.
They yelled at their friend in the water to swim toward shore, to move. “And she’s just not swimming.”
So Hudson grabbed her buoy and zipped into the water.
“I went back, and escorted her back, pushing her and saying, ‘You’ve got to swim, you’ve got to swim,’” she said. “I don’t remember much. Eventually, we got out of the water.”
The distressed swimmer was still panicky and not feeling well, Hudson said. Another swimmer took her to the hospital just to be sure she wasn’t harmed. She had no physical injuries.
The sea lion, Hudson said, “he was all around us, all around us.”
No way to know if Blondie was toxic without testing
The only way to diagnose domoic acid toxicity is through a necropsy after death, a marine animal autopsy, or veterinary tests, said Giancarlo Rulli, a spokesperson for the Marine Mammal Center, a rescue, rehabilitation, and research nonprofit based in Sausalito that’s the go-to place for reporting sick or injured marine animals in central and Northern California.
Symptoms of the gruesome brain condition, which spreads to marine mammals from things they eat that are infected — sardines, anchovies, shellfish, which get it from toxic algae — can include odd or atypical behaviors such as seizures, aggression, nervous tics, lethargy, weakness and death.
Without testing, it’s impossible to know what was going on with Blondie.
Rulli said the center had no reports on the Albany incidents, though he also said they’re getting so many calls and messages in recent months that they’re backed up and not getting back to everyone. Neither the city of Albany nor the East Bay Regional Park District had reports of sea lion sightings around Labor Day, according to spokespeople for each jurisdiction. The park district manages the shoreline as part of the Eastshore State Park.
Boobie swimmers said they had reported the Labor Day cluster sightings to the Marine Mammal Center.
“Our team is responding to an unusually high number of California sea lions suffering from domoic acid poisoning (toxicosis), with more than 150 rescued since the beginning of the year. A majority of those rescues, more than 110, have occurred since July 1,” Rulli said.
Most of these sick marine mammals, he said, as in years past, are along the Pacific coast in Monterey, Santa Cruz, San Mateo and San Luis Obispo counties.
“We do respond to seals and sea lions along the East Bay shoreline each year but it’s certainly not a major rescue location,” Rulli said.
For example, Rulli said, of the center’s 900 all-cause rescues in 2025, seven were from Alameda and Contra Costa counties, five of which were sea lions. “I don’t have a further breakdown than that,” he said. This year, Rulli said, the center is seeing “a few [rescues] in and around the bay,” but it’s still minor.
Attacks are rare but domoic acid poisoning is on the rise
The center doesn’t track marine mammal bites or attacks. But, they are extremely rare, Rulli said, especially compared with the numbers of animals at sea — an estimated 250,000 California sea lions call West Coast waters from Canada to Mexico home.
“They are uncommon considering the size of certain marine mammal populations in near-shore waters and the volume of beachgoers and swimmers that recreate annually along the California coast,” Rulli said.
He said the center had seen “a handful” of bites or abrasions in years past in waters off Monterey, Santa Cruz, San Luis Obispo and San Francisco’s Aquatic Park and “other areas where marine life intersects with high traffic human watersport activity (including swimming, surfing and paddleboarding).”
A 2015 study of California sea lion and harbor seal bites in open waters found that from 2011 to 2014, 11 swimmers reported bites — seven from seals, three unidentified and one from a sea lion. Ten of the incidents happened in the San Francisco Bay, and one occurred in Puget Sound, Washington.
Tying bites to domoic acid is also rare.
In 2025, several high-profile, frightening sea lion bites occurred in Southern California, off Long Beach (a 15-year-old girl during a life guard try-out), Oxnard (a surfer) and Monterey (a 9-year-old girl at a surf camp). These were suspected to be tied to domoic acid because they correlated with testing of marine animals in the area and toxic algae blooms, but it was not proven.
It’s hard to know what’s going on with any sea lion interaction, without testing, Rulli stressed.
“We can’t conclude why an animal may have interacted with a given swimmer. Some of these animals may be sick or injured, others may be curious, others pursuing nearby food resources,” he said.
“With or without the toxin, California sea lions can be unpredictable and territorial wild animals if feeling threatened or actively foraging. Adding domoic acid poisoning into the equation likely doesn’t help re: unpredictability.”
And unpredictability is becoming a key word for devious and deadly domoic acid.
“Domoic acid poisoning is not a new phenomenon in California. What has changed is the unpredictability, intensity and seasonality of these events,” Rulli said.
The poison used to correlate more closely with certain conditions, like algae blooms in warm water. “But we are increasingly seeing toxin exposure outside of a predictable seasonal window and during both unusually cold and unusually warm ocean conditions,” Rulli said. And while cases go up and down yearly, they appear trending upward, he said.
On average, the center responds to 70 to 90 domoic acid rescues along the California coastline yearly since 1998. This number is trending upward, with fluctuation. (In 2025, 50 domoic acid animals were rescued. Before this, it was 276 in 2024. Other high years include 2015, with 255, 2014 with 251, and 255 in 2009.)
To anyone enjoying marine waters, splashing or swimming, the center advises vigilance around sea mammals, moving away and out of the water, as calmly and quietly as possible, Rulli said.
It’s important to understand, Rulli said, “you are in their home habitat.”
The center also advises: If you encounter a sea lion or other marine mammal that appears sick, injured, disoriented or otherwise distressed:
- All wildlife can be unpredictable, but sick animals are particularly stressed and disoriented.
- Keep at least 150 feet away and do not attempt to touch, move or return the animal to the water. Exit the water calmly if approached in the ocean.
- Keep pets leashed and away from the animal.
- Call The Marine Mammal Center’s hotline at 415-289-7325..
- Be patient with responders as their teams work through an exceptionally high volume of calls and rescues.
Blue Boobies swimmers remain ‘on edge’
Many of the Blue Boobies, whose roughly 100 marine lovers come from Berkeley, Oakland, Alameda, Albany, Richmond and nearby areas, also swim with other open water groups. There is a close-knit community of ocean athletes, loosely organized under the umbrella groups of East Bay Open Water Swim, and San Francisco Bay Open Water Swim.
Since the Labor Day scare, many Boobies, including Hudson, have been back to the water at Albany.
But with added caution.
“I was on edge. It was not the blissed-out swim I’m used to. I was alert,” she said of her first dip after the incident.
“Now if there’s a sea lion on the beach or in the water, it’s a no go.”
She stresses the importance of swimming with friends, the buddy system — never alone.
She also has an added reflection.
“We know this isn’t normal,” Hudson said of the dying sea creatures. “There is a lot of sadness. A lot of us have shed tears about these animals being dead on our beach. And we know this is just one small beach along a very large coast.”
She calls it “eco-grief.” “We’re seeing it; the warming world is very obvious when you’re in the water, when dying animals are showing up on your beach. It’s our fault this is happening.”
As for swimming: “I’m taking it day by day, ultimately this is my religion, this is my theology, this is my social life, and it’s not something you give up easily. We don’t know how long this is going to last. We don’t know what the end point is.”
