On November 18, Dr. Chris Lowe took a photo for Instagram and wrote: “Out for some last season tagging ops. Still quite a few juv white sharks hanging out off some SoCal beaches. Great assists from local lifeguards.”
The Palisades Rotary Club recently hosted Shark Lab’s Dr. Chris Lowe at its weekly virtual meeting.
For the past 12 years, the lab has conducted research on great white sharks, including those who live for part of the year in Santa Monica Bay.
Lowe, a professor of marine biology and director of the Shark Lab at Cal State Long Beach, works with acoustic and satellite telemetry techniques to study the movement and behavior of sharks.
At the Rotary meeting, he addressed the increasing number of white sharks reported off the shores of Will Rogers Beach and along Southern California beaches.
Lowe, who earned a bachelor’s degree in marine biology at Barrington College in Rhode Island, a master’s degree at CSULB and a doctorate in zoology from the University of Hawaii (studying juvenile hammerhead sharks), explained that the population increase is partially due to conservation. Prior to 1994, commercial fishermen were catching the sharks—and that meat was probably used in fish tacos. Gill nets were also banned in 1994.
“A lot of people have been worried about having more white sharks in the water,” said Lowe, who noted that there have been more beach closures and more people using the beach, but there has been no significant increase in reported shark bites.
When asked how many people have died from attacks by white sharks this past year, Lowe said “There was one fatality, a surfer off Santa Cruz. He was bitten in a bad place.” The shark bite was behind the knee and hit the femoral artery.
“The main cause of death from white sharks is loss of blood,” Lowe said, noting that all surfers should know how to apply a tourniquet. “You have three minutes to stop the bleeding.”
At beaches in Southern California, “within 15 minutes a rescue helicopter can be at a site,” Lowe said. But “by and large, sharks tend to ignore people.” He grew up in Martha’s Vineyard and comes from a long line of New England fishermen and whalers.
Generally, over the last 10 years, there has been one shark fatality in Southern California every three years.
Why is Santa Monica Bay a nursery for baby whites from April to October? The female shark, when it is roughly 14 to 16 years old, will give birth to two to 15 babies after about a year’s gestation.
Lowe said that if researchers knew where they give birth, this would be the “holy grail” to shark researchers, because that is still unknown.
Once born, the juvenile sharks make their way to the shores—they favor spots in Ventura, Santa Monica Bay, Huntington Beach and San Clemente. “It appears they are a little like Goldilocks,” Lowe said. “They don’t like water too cool, they don’t like water too hot. Favorite spots for white sharks vary from year to year.”
“Sharks spend time here because it is safe,” Lowe said. “It’s warmer and there’s lots of food.
“They eat stingrays and there are so many, it’s like an ‘all you can eat pancake breakfast.’” Lowe added that in shallow water the young sharks are safer from predators.
As part of a project with the Shark Lab, juvenile whites are being tagged in several different ways. Through different methods, including satellite and acoustic receivers, researchers are starting to learn more about where the sharks go.
One juvenile made four round trips between Monterey and Vizciano Bay. “By the time he was two years old, he had covered the entire West Coast,” Lowe said, adding that the cue to migrate south is generally the cooling water temperature in October and November.
One of the tags researchers are using is a SmartTag. “It’s like a Fitbit for a shark,” Lowe said. “It stays on the shark for 24 hours and then it pops off.”
Researchers have discovered that a shark will swim in a circle for 20 minutes in one direction. Then turn and go 20 minutes in the opposite direction and then continue to repeat it. “We think this might show how a shark sleeps,” Lowe said.
When juveniles are about 10 feet in length, their diet tends to shift to marine animals. “Adults tend to swim towards offshore areas,” Lowe said, noting that there are more than 200,000 sea lions on the Channel Islands off Santa Barbara.
“There is food out there [for sharks] and fewer people. The elephant seal is the Crispy Cream of sharks. And dead whales are like a big buffet.”
The Shark Lab works with lifeguards to educate them about beach safety tips. New research is being developed with receiver buoys that would allow lifeguards to get a text alert if there were enough sharks or several large sharks that might warrant closing the beach.
Lowe said that the lab, in addition to education, is also working with conservation issues. “We’ve seen illegal targeting of juvenile white sharks by Southern California fishers.” It is illegal to fish for white sharks.
“People are chumming along public beaches,” Lowe said, noting that it isn’t illegal, but dangerous and should be illegal.
Additionally, some people have started shark tourism boats, which unlike whale watching is entirely unregulated.
The Shark Lab works with Junior Lifeguards and has also released a comic book for kids, “Beach Days – Save the Waves.”
https://www.csulb.edu/shark-lab
https://www.youtube.com/watch?v=ODD0T_s6zlI
I read this article with interest this morning as I was getting ready for my regular ocean swim :-). It is reassuring that the professor thinks that sharks are not so dangerous, I am trying to convince myself of the same, but the question is if the sharks know it (to paraphrase an old hikers’ joke about bears).
By the way, I took up ocean swimming this summer in frustration with swimming pool closures like thousands of other swimmers. I just hope they don’t close the PaliHi pool again!