Pace and California Reel California Does It Again
The great white shark next door
If wildfires, mudslides and drought were not concerning enough, the geographic range of young great whites has expanded north along the California coast by hundreds of miles
It is within feet of a teenage lifeguard on a paddle board, unaware of what's below.
"You guys looking for sharks?" the surf-camp volunteer calls out, steering his stand-up board toward Rex's Boston Whaler. He is looking for them too, an early-warning patrol meant to alert the dozens of kids on the beach about 20 yards away.
"There was a six-footer just inside your board and the beach," said Chris Lowe, the veteran scientist who runs the Shark Lab at California State University at Long Beach. "It's about six yards off your port bow now."
A slow turn, and the lifeguard calmly heads toward shore: Another great white shark has come too close to the rollicking campers nearby. He delivers the warning more than a dozen times a day. "Thanks," he calls coolly over his shoulder.
California, blessed and cursed by the extremes of its place at the continent's edge and the shore of the world's largest ocean, is learning with trepidation to live in harmony with "the man in the gray suit." It is a nickname that surfers have applied to great white sharks over the years, animals in their element, going about their business day.
If wildfires, earthquakes, mudslides and drought were not concerning enough, the geographic range of young great whites has expanded north along the California coast by hundreds of miles, bringing the quintessential summer-blockbuster predators within feet of surfers and swimmers from the Mexican border to beaches just south of San Francisco.
These are juvenile great whites, most just a couple of years old and seven to eight feet long. Unlike their large and often cannibalistic elders who more commonly live miles offshore, and often attack people by accident, the young ones have shown no interest in adding humans to their developing diets.
But their numbers are growing.
At a thriving nursery for great whites just a few miles east of this weekend refuge of a city on the border of Central and Southern California, two days with Lowe and his team revealed more than 15 great whites, some cruising no more than four feet from the beach. Many had been tagged previously by Lowe, who the year before tagged 35 great whites along the same mile-long stretch. There were, he said, undoubtedly more today.
But the great white phenomenon here is novel mostly because of the far larger geographic coastal range where juveniles are now learning to hunt before heading offshore to the cold-water island groups that have hosted the big ones for centuries.
The wider distribution of great white nurseries is the result of successful decades-old conservation efforts and a warming coastal Pacific Ocean, which scientists say has opened a near-tropical water highway for the temperature-sensitive juveniles to comfortably ride much farther north than ever before.
The trend prompted the state legislature to act three years ago, approving a $3.75million great white monitoring program. The money is a response to the new questions being raised by the animals and to the additional public safety risks more sharks might pose.
Late last month, a swimmer was bitten just south of San Francisco by a juvenile great white, the farthest north Lowe said he had ever heard of such an attack happening.
A few days later, off the island of Catalina in Southern California, a shark bumped a Boy Scout's kayak and bit into his hand. Those bump-and-run encounters, scientists say, may be more of a "nothing to see here, move it along now" signal from sharks rather than an intentional attack. But the last shark-bite fatality in the state was last year. According to state Department of Fish and Wildlife statistics, there have been 197 shark attacks and other types of encounters off the coast since the 1950s, including 14 fatal ones. Those numbers have grown each decade since the 1960s, peaking in the 2010s with 55 attacks.
"White sharks right now are beneficiaries of climate change," Lowe said. "But there are many questions about what is happening and why it is happening in these places. And as the teenage population of the white shark continues to grow, what and where are they going to eat?"
Apex predators, apex scientists
The mysteries surrounding California's great white population have grown along with the geographic scope of its nurseries.
But sharks are elusive, as a few days with Lowe's team revealed, and hard to count. Shark scientists working in labs from San Diego to Monterey Bay debate if the shark population is growing or if the "distribution" of its juvenile habitats is just giving the impression of a booming shark renaissance.
Put simply, scientists want to know: Are more white sharks in these waters? Or are these white sharks just in more places along the coast because of the warming waters associated with climate change?
The tentative answer, according to Lowe and several recent papers on the California white shark population, is yes and yes. Both phenomena are probably true.
The seminal event that prompted these new questions began in 2014. The Pacific Ocean off the U.S. West Coast has not been the same since, including the behavior of its rich variety of large mammals, diverse shark populations, and an array of other sea life.
An eastern Pacific heat wave, nicknamed the blob, shuffled the warm and cold currents that run along the California coast. The following year a periodic, if rare, weather event known as "El Niño," when warm currents surge north from the southern Pacific, reached California and exacerbated the effects of the lingering warm-water blob.
The primary consequence was that for the first time subtropical water from northerly currents from Mexico made its way around Point Conception along this county's northern coast. The outcropping — effectively the geographic gateway to Central California — had historically served as the barrier between warm southern currents and far chillier northern waters.
Suddenly, no more barrier.
Species of shellfish, anemone, commercial fish and sharks commonly native to deep Southern California and Baja were showing up in Monterey Bay — and even areas north of San Francisco. Food supplies — for migrating whales, elephant seals and sea lions, for young great whites — shifted routes and drew the large animals with them, sometimes toward shore and sometimes farther out to sea.
Salvador Jorgensen, a marine ecologist and researcher at the University of California at Santa Cruz, said juvenile great whites were hardly seen off the Central and Northern California coasts before 2014. Now they are nearly as common as the group that hangs out in the warm waters here east of Santa Barbara off a sandy beach where, on most days, you can see the Point Conception headlands in the western distance.
"If you just look there in Monterey Bay, you would say, wow, this population is just massively increasing," Jorgensen said. "But when we took a step back and looked at what the drivers are, why these sharks are up here, we realize that there's just been this massive shift in the northern boundary of warm water along California."
Jorgensen, who often works closely with Barbara A. Block, the eminent Stanford University shark scientist, said that "it seems like sharks that were previously south of Point Conception are now making it up around that corner, which has always been a big barrier thermally, and up into this region."
The warmer water, though, is only one part of what is pulling great whites into places they have never been seen before.
The turbidity, or clarity, of the ocean; the salinity; and the amount of chlorophyll in the water, which can indicate how rich in food a region is, are other factors that dictate a great white's broader movements. The research is time-consuming and remote, and the data sometimes conflicting, often bringing more questions than answers.
In one measure of how quickly habitats are emerging and changing, the experts have sought help from the amateurs to understand the new great white behavior off California.
In the paper published this year in Scientific Reports, Jorgensen wrote that "the emergence of juvenile white sharks in Monterey Bay was unexpected, sudden and outpaced established scientific monitoring programs."
What Jorgensen acknowledged was that because "shark scientists go where they know the sharks are," it was eyewitness reports from longtime surfers, divers and fishermen that first tipped him and others off that new juvenile white shark nurseries were emerging around the northern edges of the bay.
Other clues, such as an increase in bites on otters — which are not traditional great white food, being light on fat and long on thick fur — added to the evidence that the bay was full of novice juveniles testing what is edible and what is to be avoided. (Lowe jokes that otters are like "vegan brownies" for sharks — they resemble, in murky water, fatty seals, but one bite and sharks are grossed out.)
"We used a lot of citizen science data to capture this transition," Jorgensen said. "But I think the bigger danger we're talking about here is climate change. We're having a complete shift in the patterns of where these animals go, and they're showing up in new places that people aren't used to. These things are all shifting, and it makes prediction much harder."
Conservation success with an edge
The great great-white revival is a conservation triumph, albeit one with an occasionally frightening edge to it.
Although there were few solid population numbers at the time, the great white population off California was severely challenged before voters passed a 1990 ballot measure outlawing the use of gill and other indiscriminating nets set adrift in the coastal waters off Central and Southern California.
The ban took effect in 1994, when then-Gov. Pete Wilson (R) also signed into law a prohibition on hunting, catching and killing great whites off the California coast. Lowe and other shark scientists trace the white shark resurgence to those measures.
The data were scarce because traditionally commercial fishermen, working the highly productive waters of the Santa Barbara Channel and other productive fisheries, would simply list in their catch logs "shark" if they hauled one in as "by-catch" in their nets.
Not until 1975 did fishermen begin specifying if the caught shark was a great white, a bit of bureaucratic detail Lowe attributes entirely to the publication the previous year of Peter Benchley's smash novel, "Jaws."
The California conservation measures also protected elephant seals, sea lions and other favorites of the great white's diet. It was, suddenly, a good time to be a great white.
"There is a lot of food," said Echelle Burns, a sustainable fisheries researcher at the University of California at Santa Barbara, who studied under Lowe in Long Beach. "But we still don't really know why these juveniles are picking the spots they do or why they change them sometimes year to year."
Great whites, for better or worse, were suddenly pop stars. The population grew over decades, and under some pressure from the public, given the ubiquitous YouTube drone footage and GoPro highlight reels of sharks coming within feet of swimmers, the state decided it had a stake in protecting the public from its conservation successes. The $3.75 million that the state approved three years ago to establish a great white monitoring system is managed by Lowe's lab.
The program is not an early-warning system. But Lowe shares the tracking data with lifeguards along the coast and helps design protocols for when a beach should be shut down. It is tricky, subjective work with a sometimes profound economic impact on communities when beaches are closed in regions seen as havens for great whites.
During the great white population recovery, the adults ranged widely, from the "cafe" in the center of the Pacific, through California's offshore island chains, such as the northern Channel Islands off Santa Barbara and the Farallon Islands off San Francisco. The young stayed in the warm waters of Mexico and Southern California around San Diego, and sometimes off the busy beaches south of Los Angeles and in the Santa Monica Bay.
Great whites do not make happy families. Adults and juveniles remain segregated, a leave-me-alone relationship developed over millions of evolutionary years to avoid cannibalism. Adult great whites, especially males, will eat their young.
No great white shark birth, in fact, has ever been witnessed. One theory is that females give birth to pups — five, six, seven at a time — in deep, cold water such as in the trenches of the Santa Barbara Channel, among the richest marine habitats on the West Coast.
Once born, the young head instinctively toward the warm near-shore waters and the females head out to colder currents, an evolutionary security measure developed since prehistoric times. Scientists say adult and juvenile great whites behave for years as if they were two different species. In a paper published recently in Frontiers, Burns and several members of Lowe's team wrote that juvenile great whites have developed numerous "shallow, nearshore habitats across southern California," with a strong preference for sandy beaches such as this one along Padaro and Santa Claus lanes east of Santa Barbara.
It is data on the ocean's turbidity, salinity, chlorophyll, food supply and even DNA content that Lowe and his team were here to collect late last month. The beach here is mostly free of rocks, unusual for the area, and slopes so gradually into the channel that a boat can bob in 10 feet of water as far as 40 yards offshore.
Shuffle out into the light surf this time of year and, just ahead, clouds of sand rise as sting rays, many the size of old vinyl records, emerge from the sand. They are delicacies to a young great white and bountiful within a basketball-court length of the shore here.
"There are many questions about why here," Burns said. "But these sharks are not trying to eat people — that's the major thing."
A 'hot spot' on shore and off
Lowe, a marine biology professor who grew up on Martha's Vineyard and is a man in demand, calls active great white nurseries "hot spots."
This fits the description of Santa Barbara County's south coast in more ways than one. The one-mile stretch of beach where the shark nursery thrives is among the most expensive real estate in one of the most expensive neighborhoods in one of the most expensive cities in the state. These are literally movie-star homes — the majority along Padaro Lane in the eight-figure range — that look south over carefully cut lawns onto a green sea full of great whites. Ashton Kutcher and Mila Kunis, Ellen DeGeneres and Portia de Rossi, George Lucas, and Kevin Costner have all owned or been associated with property in the beachside neighborhood.
Over 15 minutes one recent afternoon, one boat with Lowe's team tracked a roughly 10-foot great white swimming languidly in slow circles about 10 yards off the beach, at times dipping into water as shallow as four feet. In the near distance, a couple tended a hedge that separated a lawn from the sand and the shark a few yards beyond.
Just a few hundred yards to the east is the beach at Santa Claus Lane, where the summer surf camps gather each year. These are gentle beaches and surf, all sand, small swell and sparse rock, ideal classrooms for aspiring surfers and predatory sharks alike.
"I use Padaro as a community learning to adapt," said Lowe, tall and lean with a narrow face that shows some of the telltale signs of a career spent in the sun. "These sharks really look at these people as flotsam, just floating trash."
Over two days, amid low ocean visibility, Lowe's team encountered at least 17 great whites, ranging in size from about five feet to more than 10 feet. The spotting is done by drone, by underwater acoustic monitors, and by good old-fashioned fin-spotting when the sea is calm enough.
To begin on an early gray day, Yamilla Samara Chacon, a graduate student responsible mainly for collecting white shark tissue, blood and other biopsy specimens, pulled on a full wet suit, strapped on a weight belt and prepared for a plunge about 30 yards offshore.
Her task: to stake monitoring devices to the sea floor in water visibility in the two- to three-feet range. The team had spotted its first white shark of the day minutes earlier, a seven-footer that had been previously tagged and was not far away.
"This isn't her favorite part of the day," Lowe said, deadpan, as Samara Chacon grimaced at the opaque ocean surface.
Then she plunged in, planted the devices, and emerged. These devices are temporary. Others are not.
With help from the state funding, Lowe now has more than 100 tracking receivers in place from the Mexican border to Morro Bay, a notorious spot for adult sharks in Central California. They ping when a tagged shark passes, allowing Lowe's team to track specific juveniles on their journeys up and down the coast.
They are itinerant, trend-driven, with one summer's "hot spot" turning into the following summer's shark-free zone. Padaro, about a 10-minute drive from the former royals Harry and Meghan's place, has endured. Lowe's radio crackles.
A smaller Boston Whaler farther offshore is using an underwater robot, extraordinarily similar in appearance to a cruise missile, to make a three-dimensional map of the Padaro area. The robot traverses the mile-long stretch at a sluggish three knots, rising and falling to take measurements.
"Oh, my God, a shark just hit the robot and breached," the voice of Emily Spurgeon, a graduate student overseeing the robot mission on this day, sounded over the radio. "It was turning and then out of nowhere the shark hit it."
"That has never happened before," Lowe said to anyone listening.
The robot is a $250,000 piece of equipment.
"Does it still work?" Lowe asked.
"Yeah, just some paint chipped where you can see a tooth mark," Spurgeon answered.
Lowe said that similar robots, some far more expensive, get hit by sharks all the time when deployed in waters home to adult sharks off Mexico at the Guadalupe Island. A lot of that is made for TV, though, with a TV budget to replace the damaged equipment.
"They think it's great," Lowe said, straight-faced. "I don't think this is great."
But the footage was remarkable, caught by a GoPro fixed to the robot: A slow turn, as the orange rudder swings right, then a shadow, a dark shape, and in a blink the mouth of a shark on the robot. As the sun tried to break through the region's traditional "June gloom," the Phyllis Ann, the boat carrying most of Lowe's team, was pursuing a nearly nine-foot great white that bears a Shark Lab tag.
But the team wanted a tissue sample to add to its database entry. This was the seventh great white spotted of the day, with sightings quickening as visibility cleared with the emerging sun and slightly clearing sea.
Zach Merson, a graduate student who had been collecting ocean samples to identify the DNA they hold, was on the bow of the Phyllis Ann with a Hawaiian sling spear cocked in his right arm. He was, at the moment, the Queequeg of Carpinteria.
Rex's drone was overhead, and as the boat approached the large shape in the water, there was a thump as Merson hit the shark with the spear, tipped with a fitting to gather tissue. No luck. The tissue sample came loose and drifted, agonizingly, to the bottom. It would happen again before the day ended.
"And no one jumped in after it," said Lowe, joking again. "These are mostly 2- and 3-year-olds, and some are getting some real heft on them."
Soon, perhaps next year, those sharks will make the 22-mile swim across the Santa Barbara Channel to the islands, a protected national park teeming with wildlife. Of the great whites Lowe has tagged here, at least 20 are out at the islands now as teens or adults.
The thriving protected sea lion and seal population is one draw.
On the westernmost San Miguel Island, Lowe said, there are an estimated 200,000 sea lions alone, a steady food source that has made more of these sharks "residents" of the area rather than the traditional migrants many are, trekking south to the Guadalupe Island, west to the so-called white shark cafe halfway between Baja and Hawaii, north to the Farallons off San Francisco.
"I mean, why migrate out to the middle of the Pacific if you don't have to?" Lowe said. "But what is true is that as the density of the population increases here, so will the behavior."
Live and let live
In 1994, the same year that great whites achieved state protection, Rob Harrington, a Waldorf School teacher, began Orca Camp along the beach at Santa Claus Lane. It has been a popular, joyful fixture of the Santa Barbara summer scene ever since.
It has also been changed by the great whites.
"Each of these past three summers, the numbers have been rising," said Harrington, 69, who operates another camp in another popular great white spot near Point Reyes, north of San Francisco. "The messages from scientists have been that if you leave them alone, if you don't harass them, they are probably going to leave you alone. That's been the case so far."
The camp's mission is to teach kids, starting at age 6, to feel comfortable in the surf. There is body boarding and soft-top surfboard lessons. There is body surfing.
"But we're also starting to give more attention to marine animals, to talk to the kids about them," Harrington said. "We tell them that this is the home of the sharks and they have been here much longer than we have. And we give the parents an abbreviated version of this."
Harrington outlines in his welcome letter to campers and parents the details of the great white nursery offshore — and only twice have parents wanted to know a little more about the camp's plans and protocols. About 150 kids pass through the camp each summer.
The precautions are simple. A counselor is posted just outside the surf line on a stand-up paddle board. When he or she sees a shark, they blow a whistle three times. The campers get out of the water. Sandcastle contests begin, friendship bracelets are woven. And usually within 15 minutes, they are all back in the water.
"We used to be able to dive beyond the surf line for these beautiful sand dollars," Harrington said. "But we won't allow the kids to go beyond the breakers anymore. That is a loss, something we miss."
"Yes, these can be very, very dangerous creatures," he continued. "But if we leave them alone and show our respect by giving them plenty of space, we are going to be safe."
The aware and undaunted
Each morning, a group of women gather to swim off Leadbetter Beach, a mile-long stretch between the Santa Barbara Harbor and a sometimes surfable point break, which itself is about nine miles west of Padaro.
No wet suits, regardless of the season. Dawn Nelson, 57, swims a mile a day with her friends. She has yet to encounter a shark after decades of the same routine.
"But I think about them every day," she said, toweling off on a chilly, fog-filled morning. "Right now I'm as scared of sting rays as anything. I did get stung by one of those."
Urchin divers, who have watched their fishery dwindle in recent years as climate change has warmed waters, have been reporting big numbers of large great whites at Santa Rosa and San Miguel islands. Some have decided it is too risky to keep diving at some spots they have plied for years.
Jeff Maassen has been an urchin diver here for decades, among other things. He keeps hemostats, essentially vein and artery clamps, on his boat along with tourniquets. He has not dived for urchin for a year. He dives alone.
"They are out there, lots of them, but we don't always see them," said Maassen, who pops up occasionally in a kelp bed with a half-eaten seal nearby. "I just move the boat and try another place. But I don't stay there."
Maassen's wife, Jane, is among the daily Leadbetter swimmers.
"We're purposely now in the shallows," she said. "We're conscious of them; there's that adrenaline. My problem is that I zigzag when I swim, and sometimes I suddenly find myself pretty far offshore and too deep. I head back in to the shallows quickly."
About eight years ago, Heidi DeBra, an Olympic prospect when she was young, rounded Leadbetter Point and, just beneath her, cruised what she called "just a really big shark." She was so close to it, she could have reached down to touch the dorsal fin.
"I tell people that it was the longest short swim back to shore I've ever done," said DeBra, 61. "Now I just swim closer."
And with that she plunged into the cloudy surf with two friends, her pink tank-style bathing suit visible from the beach during much of the swim.
The laundry list
It was the Shark Lab's second day of field work off Padaro. Spurgeon had finished robot-chasing duty, which despite the shark strike of the previous day, is generally pretty tedious work.
The lab boats were gathered near one of its buoy sensors, which the day before tracked 10 great whites in 10 minutes, all within 500 yards of the marker. On her iPhone, Spurgeon has an alert app that signals when a shark swims near this buoy, which sits about a mile offshore.
"Anything?" a colleague called to her.
"Let me check," Spurgeon responded. "Sometimes I turn off the notifications because there are so many."
Lowe set out this day with a goal of bringing a great white aboard his boat after surrounding it with nets, gradually tightening the space around it, then hauling the shark up. More tests can be performed in this riskier way, more samples taken before the shark is turned loose.
But the wind had freshened by midmorning and, frankly, the sharks were a bit larger than Lowe had in mind.
"We've got Number 3587," a voice over Lowe's radio announced, referring to a tagged great white another boat was tracking.
"Is it large? Strike-nettable?" Lowe asked.
"No, it's about six to seven feet," came the reply. "And it seems to be tagged."
Another boat had been following a five-foot great white swimming leisurely along the shoreline. Lowe came over to survey the shark.
"Way too big," he said. "We're really looking for babies."
Lowe wants at least two new sharks tagged before the day's end. So he switches to jab tagging, using a spear to attach a tracking tag near the dorsal of a young shark.
He was on the bow, looping his arms over the spear across his shoulders. The sea was green, the formless dark blobs more visible than in the flat gray light of the previous day.
On one knee, drone buzzing directly overhead, Lowe hit the great white with the tag, snapping the tip and losing the tag in the process. He replaced it and, within minutes, snapped a second.
There are no more to spare and, disappointed, Lowe draws his hand across his throat to signal the end of the mission.
"We've done a lot of research on migration," Lowe said. "But what we still don't know is why this beach on this summer. And why some other beach next summer? The laundry list of our questions grows."
Source: https://www.washingtonpost.com/nation/2021/07/23/great-white-sharks-climate-change/
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