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The Great White Way

PETE THOMAS / ON THE OUTDOORS

Scientists are excited by research that shows these dangerous ocean predators make a winter pilgrimage, for unknown reasons, to a vast offshore destination between Baja California and Hawaii that is referred to as the White Shark Cafe

September 29, 2006|PETE THOMAS

MONTEREY — Today, Monterey Bay Aquarium; tomorrow, the world.

Or, at least, the White Shark Cafe.

To be sure, the young great white that is luring visitors by the thousands to this waterfront city's popular tourist attraction has a far more exciting future in store, if he can survive into adulthood.

For The Record
Los Angeles Times Sunday October 01, 2006 Home Edition Main News Part A Page 2 National Desk 1 inches; 56 words Type of Material: Correction
Outdoors: A photo caption with an article in Friday's Sports section on great white sharks said the young shark at Monterey Bay Aquarium would be released when he reached adulthood. The shark is expected to be released when he outgrows the aquarium in the next few months, but he will not reach adulthood for some time.

After outgrowing the Outer Bay exhibit in a few months, he'll swim to Southern California and spend a year or more preying upon rays, halibut and other fish.

When he gets big enough, and hungry enough, he'll migrate north, seek larger prey and ultimately spend the fall ambushing pinnipeds at either of three main elephant seal colonies near San Francisco.

By then, he will have become eligible for an annual rite of passage scientists are only now becoming familiar with: winter pilgrimage to a vast offshore destination referred to simply as the White Shark Cafe.

"It's a place where you might go to get a bite to eat. Or you might go there to meet a person of the opposite sex," said Salvador Jorgensen, a shark ecologist leading an extensive satellite tagging effort that began last fall. "It's a little ambiguous what you're doing there. We don't know so we just called it the Cafe."

Researchers four years ago made the startling discovery that the fearsome predators leave the coast and travel as far as Hawaii, and their soon-to-be published study appears to have solved one of nature's great mysteries by pinpointing where California's white sharks spend the winter and spring.

That would be the deep and featureless Cafe area, halfway between Baja California and Hawaii.

A separate study by the Pfleger Institute of Environmental Research in Oceanside, involving white sharks tagged at Guadalupe Island off Baja California, shows that most of them also frequent the region.

What remains a mystery is why the sharks go and what they do there. It may be a mating area, possibly even a pupping area, although the latter seems unlikely since newborn sharks would have to travel extensively in open ocean to reach coastal nurseries.

It could represent a seasonal feeding site, but, ironically, the White Shark Cafe region is considered nonproductive.

"That's not to say there isn't food there, but we don't see it," said Jorgensen, who is part of a cooperative tagging effort spearheaded by Barbara Block at Stanford University's Hopkins Marine Station.

Twenty-nine sharks were fitted with pop-up tags last fall at rookeries at the Farallon Islands, Ano Nuevo and Point Reyes. So far, 5,000 days' worth of data has been collected from 20 tags, either via satellite relay or from recovered tags.

They are designed to pop free at a pre-determined time. One released prematurely along the coast before the shark had ventured offshore, and another turned up in Hawaii. The rest surfaced either in the Cafe region or in the Bay Area after the sharks had returned.

The sharks spent at least 100 days offshore and all are expected back in time for the impending elephant seal breeding season.

The sharks do not seem to be in a hurry to reach the Cafe. Their pace is about one meter per second and they dive occasionally to depths of 3,000 feet or more, perhaps to gain geomagnetic or gravitational navigational "cues" from the Earth's crust. They take an average of 25 days to get there.

Once in the area, their behavior changes dramatically. They increase their dives -- to depths of about 1,000 feet -- to about one every 10 minutes.

"That's where we start to go, 'My God, what is going on?' " said Jorgensen, pointing to compact up-and-down lines on a computer-screen graphic. "Maybe we're talking about thermoregulation. Maybe there's feeding involved. Feeding is very likely when you see something like that, but we haven't identified if there's even some sort of prey, so we really need to make a trip out there."

That could be where the young male on display at the aquarium comes in. He's eagerly gobbling salmon fillets while playing a major role in conservation and research.

He is the second white shark to have been captured in the wild and put in the 1-million-gallon Outer Bay tank, which also holds bluefin tuna, bonito, barracuda, turtles and other types of sharks.

The first was a baby female caught incidentally by a gillnet fisherman in 2004. She remained in captivity for 198 days and was labeled by Julie Packard, the facility's executive director, as "the most powerful emissary for ocean conservation in our history."

Attendance rose 30% during that period and the extra revenue was used by the aquarium to finance the latest tagging effort, which cost about $500,000. Some money also was used to supplement an ongoing juvenile white shark tagging program off Southern California.

The female shark grew to 6 feet 4 and 162 pounds before being fitted with a 30-day tag and set free. The tag popped off near Santa Barbara.

The male shark, caught on hook and line by researchers off Malibu, was 5 feet 8 and 104 pounds when he went on display Sept. 1. On Sept. 3, 17,000 people visited the aquarium, a single-day record.

"I think people were kicking themselves for not having seen the first one," said aquarium spokesman Ken Peterson.

Though he is currently dwarfed by massive tuna and a few other animals in the tank -- full-grown white sharks can measure 18 feet and weigh more than 4,000 pounds -- the young male swims with the telltale swagger of a predator and is generally afforded a wide berth.

"There he is!" tourists whisper, pointing or raising camera-phones as he swims by. For most, this is the only live great white they will ever see.

Still, not everybody understands what all the fuss is about.

"To tell you the truth I am not very impressed," complained Pat Martin, a visitor from New Jersey. "I thought he was going to be much bigger."

pete.thomas@latimes.com

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