Researchers in Southern California are seeing more great white sharks than ever before, reports local broadcast network KCAL-TV.
Chris Lowe, a shark expert at California State University Long Beach, tells KCAL-TV that his lab tagged a record 38 great whites—more than three times the number they tagged last year. “This year there were just more sharks around, and the question is why,” says Lowe.
But scientists emphasize an important qualifier: The great whites cruising the Southern California coast are babies and juveniles that tend to be between four and ten feet long. These skittish young sharks stick close to shore to avoid predators and snack on stingrays and fish.
They also mostly avoid people, even as they’re becoming more numerous.
“Despite the fact that shark populations are going up and more people are using the water than ever before, we’re not really seeing more people actually being bitten by sharks,” Lowe tells Reuters. “In fact, in some years, the rate has gone down. So what that tells us, as a scientist, is that we’re not on their menu at all. But occasionally accidents happen.”
Previous research from Lowe’s lab identified Southern California spots—including Ventura, Oxnard, Santa Monica Bay, Huntington Beach and Dana Point—as nurseries for the famously toothy predators, reported Cheri Carlson of the Ventura County Star in 2017.
Typically the immature great whites just spend the summer off Southern California, when the water is relatively warm, before heading south to Mexico and Baja as winter chills the sea. But this year Lowe says the sharks are sticking around.
“Normally they’d be leaving by now, but instead we are seeing more sharks than ever,” Lowe tells the Guardian's Katherine Gammon.
Lowe tells Laylan Connelly of the San Jose Mercury News that his team doesn’t have enough data to draw any hard conclusions yet, but water temperature is part of what dictates whether the sharks stay or leave. “If our water temperature doesn’t cool down, the sharks that normally leave have no reason to leave. So we’re just going to wait and see,” Lowe says.
This year’s monitoring also revealed groups of young sharks spending time in places farther north, where the water was once too cold for them to linger. “To us, that’s a harbinger of climate change,” Lowe tells the Mercury News, “that’s a classic sign of species moving north and tracking conditions that are more suitable.”
But even as climate change shuffles the growing sharks’ favorite haunts, the population’s growing size is a good sign for the sharks and California’s marine ecosystems. More sightings mean that protections for great whites enacted by the state in 1994 have worked. The Marine Mammal Protection Act has also likely helped the sharks by protecting the favorite food of adults: marine mammals.
“It’s taken this long to finally start seeing the results of protection, [but] they’ve finally reached a tipping point,” Michael Domeier, a shark researcher at the Marine Conservation Science Institute, told Surfline's Dashel Pierson in 2017 following numerous sightings in Orange County. “This is not a fluke. It’s our new reality. And we just have to get used to it.”
But a two-year drone study conducted by Lowe on the behavior of great whites near Southern California shores found they were mostly indifferent to people nearby. Lowe tells the Guardian that sharks may actually be making the beaches a bit safer by keeping the stingray population down.