Shark at­tack rates in Cal­i­for­nia plunge 90 per cent since 1950s

Even with thou­sands more peo­ple in the wa­ter, study says

Cape Breton Post - - CLASSIFIEDS/LIFESTYLES - BY CHRISTO­PHER WE­BER

Swim­mers and surfers to­day are about 90 per cent less likely to be at­tacked by sharks off Cal­i­for­nia’s coast than they were in the 1950s, even though there are hun­dreds of thou­sands more peo­ple in the wa­ter, ac­cord­ing to a new study.

The find­ings mark a stark con­trast to re­cent head­lines out of North Carolina, where a record num­ber of shark at­tacks have been re­ported this year. Eight peo­ple were bit­ten in the past three weeks alone.

More re­search is needed to ex­plain the ap­par­ent dis­par­ity, said Francesco Fer­retti of Stan­ford Univer­sity’s Hop­kins Marine Sta­tion.

What the study did show was that although the re­ported num­ber of at­tacks along Cal­i­for­nia has risen slightly over the past six decades, the risk of at­tack has plum­meted, ac­cord­ing to Fer­retti and fel­low Stan­ford re­searcher Fiorenza Micheli.

“Con­sid­er­ing how many more peo­ple are out there in the ocean, we should ex­pect many more at­tacks,” Fer­retti said Thurs­day.

Re­searchers said the de­cline likely was the re­sult of sharks fo­cus­ing their at­ten­tion on their nat­u­ral prey, such as sea lions and ele­phant seals - whose pop­u­la­tions have surged in re­cent years thanks to con­ser­va­tion ef- forts.

There might also be fewer sharks in the wa­ter, they said. It’s been tough his­tor­i­cally to track shark pop­u­la­tions.

On av­er­age in the 1950s, Cal­i­for­nia saw less than one at­tack on hu­mans per year, Micheli said. That num­ber has gone up to about one or two at­tacks a year over the past decade.

The hu­man pop­u­la­tion in coastal Cal­i­for­nia tripled dur­ing the same pe­riod - from 7 mil­lion in the 1950s to 21 mil­lion in 2013, the study said. Mean­while, the num­ber of surfers, scuba divers and beach­go­ers has spiked.

In De­cem­ber, a ju­ve­nile great white pulled a man off his surf­board along the Cen­tral Coast. That was about 50 miles up the coast from the site of an at­tack on a surfer near Vandenberg Air Force Base in Oc­to­ber. Both men sur­vived.

In North Carolina, most of this year’s at­tacks hap­pened in shal­low wa­ter. The eight re­ported in the past three weeks broke a record for the most shark bites off the state’s coast in the 80 years in which records have been kept.

Fer­retti said more re­search is needed to de­ter­mine what’s be­hind that spike. Some ex­perts say it might be re­lated to an un­sea­son­ably hot June that rapidly raised ocean tem­per­a­tures off North Carolina and prompted fish to mi­grate north ear­lier than usual.

In Cal­i­for­nia, re­searchers put the odds of a swim­mer get­ting at­tacked by a great white at about one in ev­ery 738 mil­lion beach vis­its.

“You have a bet­ter chance of win­ning the lottery,” Fer­retti said. For surfers, the chances were one in 17 mil­lion.

“It’s a say­ing in the com­mu­nity: You’re more at risk of get­ting hit by a fall­ing co­conut,” said Chris Plante, an as­sis­tant cu­ra­tor at Aquar­ium of the Pa­cific in Long Beach. “I don’t have num­bers to back that up, but I do know you’re more at risk of get­ting bit by a dog than a shark.”

Swim­mers and surfers can fur­ther re­duce their risk by tak­ing to the wa­ter in the spring. At­tack rates vary through­out the year, with the high­est in Oc­to­ber and Novem­ber and the low­est be­tween March and May. The pat­tern matches sharks’ sea­sonal shifts in mi­gra­tion, Fer­retti said.

At­tacks are much less likely in San Diego, Or­ange, Los An­ge­les and Ven­tura coun­ties. That’s be­cause sharks in South­ern Cal­i­for­nia tend to be ju­ve­niles, so they’re smaller and less dan­ger­ous, re­searchers said.

As they grow, they mi­grate north to find prey, so they’re more dan­ger­ous in North­ern Cal­i­for­nia.

AP PHOTO In this Aug. 26, 2011, file photo, life­guard Am­ber Presta­gard passes a sign alert­ing beach go­ers to a shark sight­ing at Mis­sion Beach in San Diego. Swim­mers and surfers to­day are about 90 per­cent less likely to be at­tacked by sharks off Cal­i­for­nia’s coast than they were in the 1950s, de­spite the fact that there are hun­dreds of thou­sands of more peo­ple in the wa­ter, ac­cord­ing to a new study.

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