Leviathans may battle in remote depths

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In what could be the ultimate marine smack-down, great white sharks off the California coast may be migrating 1,600 miles west to do battle with creatures that rival their star power: giant squids.

A series of studies tracking this mysterious migration has scientists rethinking not just about what the big shark does with its time but also about what sort of creature it is.

Few sea denizens match great white sharks and giant squids in primitive mystique. Both are the subject of popular mania; both are inscrutable. That these two mythic sea monsters might convene for epic battles on the stark expanses of the Pacific is enough to make a documentarian salivate.

For more reserved scientists, the possible link between sharks and squid, suggested by marine ecologist Michael Domeier of the Marine Conservation Science Institute in Fallbrook, is just one part of emerging research that has altered their understanding of the great whites.

The shift began eight years ago with the surprising discovery that great white sharks migrate, somewhat as humpback whales do. That and subsequent studies have demolished the iconic image of Great Whites lurking in relative shallows, ready to snatch an errant swimmer, as popularized in the movie “Jaws.”

Domeier said he believes the animals “are not a coastal shark that comes out to the middle of the ocean. They are an ocean shark that comes to the coast. It is a complete flip-flop.”

Picture them not as a dorsal fin off the beach but rather as an unseen leviathan swimming through black depths where the oxygen thins and fish glow in the dark, and maybe pouncing on a 30-foot squid.

The squid part is controversial. But Domeier’s work and that of other scientists increasingly suggest that great white sharks are not randomly roving eating machines. Instead, they obey set migration patterns, have distinct populations and return to the same locales. They are not desperadoes but dutiful migrants: Nomads but not outlaws, they yearn for home.

But this new understanding raised a question: Why would an animal so large, that grows teeth as humans grow hair, bother to go so far when it can dine on just about anything in fin’s reach? The migration is especially puzzling because it means sharks miss out on coastal food supplies, said the University of Hawaii’s Kevin Weng, who also tracked sharks’ migration.

Determined to find the reason, Domeier and his team spent three years catching 22 great whites off Guadalupe Island, southwest of San Diego and bolting high-tech tags to their fins. The area, like California’s Farralon Islands, is a hot spot for shark visits.

The team used hooks that could cradle a volleyball. They wrestled the sharks onto platforms, lifted them aboard their vessel and put towels over their eyes. The 4,000-pound predator is only a minor threat out of water, Domeier said. But after being thwacked off his feet, he learned to tie up their tails.

Funded by Newport Beach’s George T. Pfleger Foundation and others, Domeier arranged a voyage with a National Geographic Channel television crew to follow the sharks in a 126-foot boat. The crew used the tags to track the sharks to an area of the deep Pacific about 1,500 miles east of Kauai that scientists consider an ecological desert because it is so biologically unproductive. There, the sharks abruptly ended their migration, and satellite tags showed them milling around and diving.

Despite hours of surveys and trolling during last spring’s monthlong voyage, members found barely any fish or other prey that the sharks might be eating.