Researchers have discovered a “dramatic increase” in the number of white sharks swimming in Monterey Bay in recent years, including an area near Santa Cruz County where a surfer died last year, according to a new study published Tuesday.
Large juvenile white sharks (younger animals 5 to 9 feet long) that were traditionally concentrated in warm waters of northern Mexico and southern California have moved north since 2014 as they has heated the water temperature.
Where once there were no young white sharks observed in the ocean between Manresa State Beach in Aptos and New Brighton State Beach in Capitola, now dozens are seen each year, according to research by scientists at the Aquarium of Aptos. Monterey Bay, Duke University and the state of California University of Long Beach. They swim in groups between April and October, sometimes a few feet off the coast and other features such as the “Cement Boat,” a dilapidated boat coming out of a dock at Seacliff State Beach. Sharks have been regularly photographed swimming close to people, who often have no idea that powerful creatures are so close.
“I’ve seen sharks under the surfers, a few feet away,” said Chris Gularte, chief pilot of Specialized Helicopters, a Watsonville travel company that regularly flies over the area. “When the water is warm and they reach the bay, you can see them swimming close to people all day. The paddlers and kayakers standing there will approach them and not realize they are there.
Gularte said he has not seen sharks from his helicopter at Santa Cruz’s most famous surf spots, such as Steamer Lane in Santa Cruz or Pleasure Point, near Capitola. He said he has seen an increase in the number of sharks at the mouth of the Salinas River and San Francisco Bay.
In a tragic interaction last May, surfer Ben Kelly, 26, from Santa Cruz, was bitten about 100 meters from the shore on Manresa State Beach in Aptos. The bite occurred behind his right knee, hit an artery and he died bleeding. An investigation by state wildlife biologists found that the shark was at least 10 meters long, larger than the young ones that have mostly congregated a few miles north.
Investigators said Tuesday that such attacks are rare. According to them, the influx of young sharks in northern California is indicative of major ocean changes underway due to climate change affecting many species.
“What’s happening here has been really weird, different and unusual, and not what we’re used to,” said Kyle van Houtan, chief scientist at the Monterey Bay Aquarium. “Monterey Bay is famous for cold water, seaweed, otters, anchovies and whales. One thing that hasn’t been here is the juvenile white sharks. But in the last five years or so, that has changed completely. “
In Southern California, scientists last year tagged 53 juvenile white shark transmitters, said Chris Lowe, a marine biologist at Cal State Long Beach. Labels send a signal as they approach four special buoys in Santa Barbara, Huntington Beach, Long Beach and San Clemente, and beach lifeguards receive a text warning them of sharks in the area.
Lowe said he is working with officials at the Monterey Bay National Marine Sanctuary to try to establish a similar system from Seacliff State Beach to New Brighton State Beach, an area that area residents are increasingly calling “Shark Park.”
He noted that great white sharks generally avoid people and, when they bite someone, it is almost never a sustained attack. It’s a single bite and then they leave.
“We don’t really know the motivations of sharks when these things happen,” he said. “At best, we think the shark made a mistake: they thought they were going to look for a fish or a seal.”
After birth, great white sharks stay in warm waters near the coast to feed on fish, rays and squid, said Sal Jorgensen, a marine researcher at UC Santa Cruz and co-author of the study, published in Scientific Reports, a peer-reviewed journal from Nature publishers.
After two or three years, they grow more than 10 feet long and swim to colder, deeper waters. His teeth widen and become more serrated. They reach 17 to 19 feet in length and eat sea lions and other marine mammals, often in colder waters in places like the Farallon Islands.
The “shark nurseries” where they grow are usually south of Santa Barbara County. But after the Pacific Ocean, on the west coast, warmed considerably in an event known as “the blob” in 2014, warmer conditions have shifted north, scientists found. Warm conditions endured the El Niño events in 2015-16 and 2018-19 and continue today.
Tyler Fox, a professional surfer who has been sailing in the Aptos area for years, said he has noticed a change.
“People are watching them more and more in the water,” said Fox, editor of Santa Cruz Waves magazine. “A couple of my friends swam less than 10 feet. The frequency of the meetings has definitely increased. “
Fox said surfers he knows did not return to the Manresa beach area after Kelly’s death. But now, especially in the colder months, when sharks are not believed to be there, surfers are back. He said he sailed there on Sunday.
“There are always lucky situations, but I think in that particular area, they cross, hang out and warm up,” he said. “They are not in hunting mode. They won’t reach you as you see Jaws with a fin directly at you. I think it’s pretty safe. “
