CSU Long Beach shark lab has tagged a record amount of white sharks, sig­nal­ing a healthy ecosys­tem – and warmer water­sChris Lowe is no longer sur­prised when he sees drone footage of juve­nile white sharks cruis­ing near surfers and swim­mers in south­ern California’s ocean waters.Lowe directs the shark lab at Cal­i­for­nia State Uni­ver­si­ty, Long Beach, and for the past 12 years he’s been mon­i­tor­ing pop­u­la­tions of juve­nile white sharks off the south­ern Cal­i­for­nia coast with tags, drones and planes. This year, Lowe has already tagged a record 38 sharks, triple the num­ber that were tagged last year. “Nor­mal­ly they’d be leav­ing by now, but instead we are see­ing more sharks than ever.”Two years ago, Lowe was asked by the state to inves­ti­gate in more detail what sharks are doing along the beach­es and how they behave in prox­im­i­ty to peo­ple – research that offi­cials hope will help pre­dict where and when the sharks show up and will help edu­cate the pub­lic about the animals.White sharks have been affect­ed by humans for more than a cen­tu­ry. Com­mer­cial fish­eries caught them for years (many a fish taco was prob­a­bly shark, Lowe said) and sharks’ pri­ma­ry adult food – marine mam­mals – has been hunt­ed to the brink of extinction.California moved to pro­tect its white shark pop­u­la­tion in 1994, and has seen its num­bers rise steadi­ly since. In south­ern Cal­i­for­nia, most sharks spot­ted near beach­es are juveniles.White sharks are born at 4.5 to 5ft long, and grow a foot each year for their first five years of life. They love south­ern California’s shal­lows because the water is warmer (young sharks lack the abil­i­ty to retain heat in cold­er waters), safer from preda­tors and full of their pre­ferred food: stingrays. When they reach 10ft, they switch food sources to marine mam­mals like seals, and they spend more time away from the shoreline.Lowe stud­ies the ani­mals from the land, in the water and from the skies.He works close­ly with life­guards, who are on the front­lines dur­ing the sum­mer and fall beach sea­son. His team also goes out to tag sharks, when they try to sur­gi­cal­ly implant the ani­mals’ back with a fin­ger-sized acoustic trans­mit­ter that con­nects with lis­ten­ing sta­tions all along the coast­line.> Head­ing out to look for baby white sharks to tag w/ Dr. Chris Lowe of CSULB’s shark lab. pic.twitter.com/UMNqhlHLwz> > — Jill Replogle (@jillrep) June 28, 2017The acoustic sta­tions dis­play where the sharks are spend­ing their time, and they allow the research team to track indi­vid­ual sharks for years – even when they cross the south­ern bor­der with Mex­i­co to Baja Cal­i­for­nia. Some of the trans­mit­ters will last for a decade. “It’s a lit­tle like how you get a bill at the end of the month for a toll road,” said Lowe. “We use the same tech­nol­o­gy – the only dif­fer­ence is we get the bill, they don’t.”> New ani­ma­tions by @native.illustrator show­ing how our pas­sive acoustic teleme­try shark track­ing tech works. shark­spies track­ing­not­slack­ing pic.twitter.com/W5zzna4TAZ> > — Chris Lowe (@CSULBsharklab) Sep­tem­ber 18, 2020In addi­tion to tag­ging and track­ing, the team also uses an autonomous under­wa­ter robot that can rise up and down and looks like a tor­pe­do. It car­ries a full set of oceano­graph­ic sen­sors on its nose and a video cam­era. The robot allows the researchers to make high-res­o­lu­tion three-dimen­sion­al maps, and study why sharks are hang­ing out where they are: is it because there are more stingrays, warmer water, or few­er people?Aerial drones are the team’s final piece of tech – the researchers fly drone sur­veys from the San Diego bor­der with Mex­i­co to San­ta Bar­bara, to iden­ti­fy sharks’ loca­tion and size, and to see when they are close to peo­ple. “We can go through and count how many peo­ple are in the water, surfers, fish­ers, pad­dle board­ers, and plot the dis­tance to any shark,” Lowe said.Lowe has found that not only are there more kid-sharks in the waters, they’re around longer, too. Juve­nile white sharks typ­i­cal­ly leave Cal­i­for­nia waters for Baja Cal­i­for­nia in the fall, and return in the spring, but that pat­tern has been chang­ing – prob­a­bly due to warmer waters and an abun­dance of food. “We may have white sharks here year-round,” he said.Up in Mon­terey Bay in north­ern Cal­i­for­nia, David Ebert, who directs the Pacif­ic Shark Research Cen­ter at Moss Land­ing Marine Lab­o­ra­to­ries, has seen a sim­i­lar rise in num­bers of juve­nile white sharks off the coast.Ebert recalled tak­ing a heli­copter ride in 2015 over the Mon­terey Bay and being astound­ed by what he saw from the sky: lit­tle sharks hang­ing out in small groups, right off the beach.On one hand, the grow­ing pres­ence of the juve­niles is a good sign, he said, because it shows the ecosys­tem is clean and there is enough food to sup­port the sharks. But it also points to how the cli­mate cri­sis, and warmer ocean tem­per­a­tures, can shift the range of the ani­mals. South­ern Cal­i­for­nia used to be at the north­ern lim­it of their range, and now it might be in the mid­dle, Ebert said.Even with more sharks in the water, Ebert said humans have lit­tle to fear from the juve­niles. Since 1950, when the state start­ed keep­ing records, there have been on aver­age only three or four attacks a year in Cal­i­for­nia, Ebert says – even as the state pop­u­la­tion has swelled from 15 mil­lion to 40 mil­lion. “There are so many peo­ple in the water: you have pad­dle boards, kayaks, wet­suits, but the num­ber of attacks hasn’t real­ly changed. That tells you that peo­ple are not on the menu, they’re not out here hunt­ing people.”“They’re an amaz­ing ani­mal to see in per­son,” he added. “I think it’s one of those rare wildlife expe­ri­ences, you can spend your whole life out there on the water and nev­er see one.”Lowe, too, said that gen­er­al­ly when he sees sharks swim­ming around peo­ple, the peo­ple have no idea – and the sharks gen­er­al­ly don’t care.He and his team now hope to cre­ate a shark fore­cast – “it’s going to be a sharky week!” – that can help edu­cate beach­go­ers about the sharks in California’s waters. Lowe said he could see a future where life­guards can post signs about where the juve­niles are hang­ing out, along­side infor­ma­tion about the tides and waves. He says that if you hap­pen to see a group of sharks on the beach, it’s actu­al­ly a cause for cel­e­bra­tion: “They are keep­ing the stingray pop­u­la­tion down, and they gen­er­al­ly don’t care about people.”