APTOS, Santa Cruz County — A white shark glided slowly, its dorsal fin barely breaking through the water in a protected cove of Monterey Bay.
In a boat trailing just behind, a researcher thrust out a pole to attach a satellite tag to the back of the 7-foot-long juvenile, which thrashed around briefly before diving below.
It seemed all too easy. Within two hours, the team of researchers from Monterey Bay Aquarium and Cal State Long Beach tagged four juvenile white sharks and observed two or three others, all within a short swim of a popular Santa Cruz County beach. It was the first time the team had tagged them north of Santa Barbara.

Also known as great whites, the juvenile sharks began spending summer and fall at what’s now called Shark Park, a part of Soquel Cove just off Capitola and Aptos, after warming ocean temperatures began drawing them north in 2014. Drone footage has caught them cruising right below hapless swimmers, and they’re likely responsible for a rash of sea otter deaths. But even though the sharks are so common from June to November that they’re touted in local whale-watching trips, scientists still know very little about them.
“It’s good to get out and get tags in animals to figure out: Why are they here? What are they doing while they’re here?” said Chris Lowe, professor of marine biology and director of the shark lab at Cal State Long Beach. “How close do they get to people, and do they pose a risk?”
The young sharks’ presence in Monterey Bay drew attention after surfer Ben Kelly was killed at an Aptos beach in 2020, and swimmer Steve Bruemmer was severely injured at Lovers Point at Pacific Grove this summer. Both incidents appear to have involved larger adult white sharks, based on the size of the bite marks, and juveniles have not been known to bite anyone in Monterey Bay. Still, their risk needs to be assessed, said Lowe.

A juvenile white sharks swims in Monterey Bay’s Soquel Cove.
The white sharks in Monterey Bay are mostly around 3 or 4 years old and 7 feet long, about half as long as the “Jaws” variety. Sensitive to cold when very young because they lack the bulk to retain heat, they typically would stay between San Diego and Santa Barbara in summer and fall and head to Baja California in winter.
Adult white sharks, on the other hand, spend the majority of their time farther offshore, including at the Farallon Islands in fall, and a mysterious zone between Baja and Hawaii known as the White Shark Cafe in winter and spring, scientists recently discovered. Though not classified as endangered, the species cannot be fished or hunted in U.S. waters.
Juvenile white sharks began venturing up the coast in 2014, when a marine heat wave linked to climate change likely created a channel of warm water that led them to the bay’s prime feeding grounds. They landed in the particularly warm Soquel Cove, which is protected from wind and big waves by nearby Pleasure Point. But they haven’t stopped coming north even after overall ocean temperatures cooled.

Scott Reid of the Monterey Bay Aquarium steers the boat as James Anderson (left) of Cal State Long Beach’s Shark Lab works to place satellite tags on white sharks in Soquel Cove.
Last week, the tagging process started with Cal State Long Beach graduate student Patrick Rex operating a drone about 30 feet above the water in what he called a lawn mower pattern until he located a shark. Once he did, he directed boat pilot Scott Reid, manager of collections at the aquarium, to its location.
The shark was basking, or swimming slowly in the warm upper layer of water to conserve energy. It glided with its pectoral fins outstretched like airplane wings, its tail rhythmically moving it forward, and barely seemed to notice the boat.
“They definitely seem to be in a meditative state,” said CSU Long Beach post-doctoral fellow James Anderson, who was in charge of tagging. “Maybe they’re asleep. We really don’t know.”
Anderson’s first job was to determine the gender of the shark by angling a Go-Pro camera under the animal. He then checked the camera footage to see if it was male or female based on whether it had claspers, male genitals sometimes described as looking like two chopsticks next to each other.


The shark startled and breached when it noticed Anderson behind it, but Rex kept the drone overhead and was able to quickly find the shark again so Anderson could proceed with tagging. In all, the team put tags on 12 animals last week, the total allowed under their permit with the Monterey Bay National Marine Sanctuary for the year.
The devices will document the young sharks’ movements — both location and depth — and the light and temperature of the water. Though some information will be available immediately via satellite, the scientists will get more high-resolution data after the tags pop off automatically and bob to the surface in either six or nine months, when they can be collected.
“We’re trying to learn how they’re utilizing the temperatures and areas of Monterey Bay, hopefully capturing cues on when they leave, the paths they take and where they go,” said John O’Sullivan, director of collections at Monterey Bay Aquarium.

A white shark thrashes in the water as James Anderson of Cal State Long Beach’s Shark Lab works to place a satellite tag on it off the shore of in Monterey Bay’s Soquel Cove.
The aquarium needs to know this in part because it has a sea otter surrogacy program in which captive female otters raise orphaned pups that are later reintroduced to the Monterey Bay area as part of a statewide effort to reestablish the endangered marine mammal.
“During the time these sharks started coming up here, we saw an increase in mortality of sea otters from shark bites,” said O’Sullivan, who said the aquarium may change the time it releases sea otters when they know more about when and where the sharks go. “We have two protected species, one being detrimental to the other one, and it’s a challenge to figure out.”
Juvenile sharks at this stage are expanding their diet from rays and other fish to marine mammals, according to O’Sullivan.
“In fact, their teeth are changing from being thin and sharp to being triangular and serrated,” he said. “They’re going through a learning curve of how to target their prey item, which isn’t sea otters.”

James Anderson of Cal State Long Beach’s Shark Lab prepares to place satellite tags on white sharks in Monterey Bay’s Soquel Cove.
Sea otters rely on their high-density fur to keep warm, rather than the highly caloric blubber of sea lions and elephant seals, which is what adult white sharks need.
“So they’re making, we feel, mistakes,” O’Sullivan said.
Lowe said that white sharks may occasionally bite humans for the same reason — mistaken identity.
“Then once they bite that individual, they realize it’s not what they thought,” Lowe said. “And that’s why people aren’t consumed — that’s why flesh isn’t removed. They’re bitten, and then they’re left alone.”
Unfortunately, though, such bites can still be fatal.

Andre Boustany launches a drone to get an overhead view as researchers with the Monterey Bay Aquarium and Cal State Long Beach’s Shark Lab work to place satellite tags on white sharks in Monterey Bay’s Soquel Cove.
When it comes to young white sharks, however, Lowe found in a recent study that they are a low risk to humans at Southern California’s crowded beaches. Young white sharks aggregate there close to shore to avoid predators, such as larger white sharks — which sometimes dine on juveniles of the same species — and orcas. Other than feeding on fish and rays, they spend the rest of the time cruising the warm water, mostly uninterested in humans.
“People are encountering juvenile white sharks every single day in Southern California,” Lowe said. “Yet when we compare that to the number of bites, it’s hugely disproportionate.”
There’s still a lot scientists don’t know about California white sharks, including where they give birth and how often. They also don’t know how large the population is, though they believe it has increased after the adoption of regulations that have protected sharks and their prey, including the 1972 Marine Mammal Protection Act.
“Sharks are part of a healthy ecosystem,” O’Sullivan said.

A juvenile white sharks swims in Monterey Bay’s Soquel Cove near Aptos (Santa Cruz County) as researchers with the Monterey Bay Aquarium and Cal State Long Beach’s Shark Lab work to place tags on white sharks.
Eric Mailander, a local fireman and sports fisherman, was the first to document young white sharks coming into Monterey Bay. After taking drone footage and meticulously logging shark sightings in his spare time, he became co-author of a scientific study with Lowe and others about the sharks’ arrival in the area.
“Call me crazy,” said Mailander, who has loved sharks since he was a small boy. “On my days off, I’m out here constantly.”
After taking drone footage of the sharks swimming harmlessly under swimmers, Mailander is one of the locals who has found more of a positive than a negative side to having so many white sharks in the bay.
“They’re finely tuned for speed. They’re neat-looking,” he said. “They’re just fascinating.”
Source: SF Chronicle