Sharks have spots they like and are closer than you think, Shark Lab study shows
Sharks are hanging around some of Southern California’s busiest beaches — and they are closer than you think.
No need to cue the “Jaws” song, they don’t seem to be much interested in the humans they are sharing the water with.
A new academic paper published last week analyzed eight years of data compiled by Cal State Long Beach’s Shark Lab and says “hot spot” areas of young sharks are located at some of the country’s busiest and most populated beaches.
James Anderson, lead author of the paper and postdoctoral research fellow at the Shark Lab, compiled historical information gathered by graduate students through the years using electronic tracking data that showed where sharks congregated from 2010 through 2018.
“We’re seeing these large numbers of animals utilizing these small, distinct areas,” said Anderson, who lives in Orange. “Some of them are very highly populated yearround.
“Some coincide with beach season when beaches are packed with people, both in and out of the water, and it doesn’t seem to deter their behavior.”
Some sharks were shown just yards from the shoreline, says the paper, published in the journal Frontiers in Marine Science.
The group of sharks stayed in these hot spots — located in the Santa Monica Bay and South Bay, Long Beach, Huntington Beach and Surfside, as well as further south in Dana Point and
San Clemente — sometimes for days and at other times for months.
“What’s really interesting is the location of these aggregation hot spots have shifted from year to year, rather than remaining consistent over time. This isn’t something that’s been described in juvenile white sharks elsewhere in the world,” Anderson said. “Not only that, but more often than not, these hot spots have been located at some of California’s most heavily used beaches and densely populated areas.”
The study analyzed the movement of not just neonates, or babies, but also sharks that range from ages 2 to 4, which can get into the 10-foot range.
When beachgoers hear the sharks are lingering in the water near where they are recreating, most of the time they are surprised, Anderson said. “They are there, we know from the studies.”
Technology in recent years has helped give researchers a better look at the sharks’ movement patterns, with each year more sharks tagged for tracking. Drones help give an overhead look at the ocean, where sharks can be seen next to surfers and swimmers.
For sharks to hang around these populated areas, there must be a food base.
“They are not eating people,” Anderson said.
Instead, they are after stingrays and fish, which means the environment is healthy.
“The water quality isn’t as bad as you think in these heavily populated areas — the food base they need to thrive and survive is clearly there to support the high numbers for a long period of time,” Anderson said.
Still, there remains mysteries about the apex predator, he said. “It’s still a developing picture.”
Some of the questions remaining: What is causing them to aggregate and why do they choose certain beaches? Why are they opting to change locations year after year?
Early years of data, from 2010 to 2014, showed the sharks off Santa Monica, Will Rogers State Beach, Manhattan Beach and Redondo Beach.
Then, in 2015, they shifted south to Long Beach, Surfside and Huntington Beach. The sharks stayed there for a few years, then they shifted to San Clemente and Dana Point in 2017.
In 2018, they headed north to Santa Monica and Carpinteria.
“We don’t know for sure,” Anderson said of their reasons for gathering at new spots. “It’s widely regarded that temperature is a key player. They seem to have specific thresholds they really like.
“That’s only one factor,” he added. “There has to be more factors of why they move to these areas.”