Sunday, October 29, 2006

Seeing Great White sharks on a different angle

Trenton Wheeler is just 5 years old, but he is already a "stalker" of great white sharks, in the words of his father, Kevin. And at this point there is just one place in the world for Trenton to pursue his obsession: the Monterey Bay Aquarium.

For half a century, aquariums around the world have tried unsuccessfully to maintain a captive great white, the shark immortalized in the 1975 movie "Jaws" and its sequels, for more than a couple of weeks. Two years ago, scientists at Monterey managed to pull off this feat for the first time, keeping a female great white in their million-gallon tank for six months. Since September they have been at it again, introducing a year-old male to thousands of tourists who have flocked to view it.

A young great white swims past visitors at California's Monterey Bay Aquarium, where the shark has been displayed since September. (Randy Wilder -- Monterey Bay Aquarium)
Monday, Oct. 23, 1 p.m. ET

Science: Great White SharksWashington Post science writer Juliet Eilperin will discuss her Monday Science Page story about the efforts to hold a great white shark in captivity.

Trenton Wheeler is one of these tourists, a San Jose resident who persuaded his father, sister, aunt and cousin to make the trek to Monterey in mid-October so they could peer at the 100-pound creature through a 13-inch-thick acrylic wall in the aquarium's Outer Bay exhibit.

"Here's the great white!" he cried out as the shark appeared from the depths, looking -- at just under six feet long -- decidedly less threatening than the full-grown version that has terrorized humans for generations. A full-grown great white can be up to 20 feet from snout to tail.

Aquarium officials are hoping all their visitors will be equally fascinated, and inspired to help protect a species that is under assault despite being protected by international treaties and California law. Numbers of great whites die after getting tangled in fishermen's nets, and in some countries people hunt them for their fins and meat.

"We take advantage of people's morbid curiosity about great white sharks to get the word out that these animals are the victims, not the villains, of the sea," said Michael Sutton, who directs the aquarium's Center for the Future of the Oceans. "The white shark is the most protected shark species in the world, but they're still killing them left and right in Mexico and other places."

Because great whites are such fierce predators, grow to an enormous size and like to range over thousands of miles in the open ocean, they are more difficult than other sharks to keep in a tank, even temporarily. In the mid-1980s, Monterey's biologists acquired one, but it died in less than two weeks; Randy Hamilton, now vice president and director of husbandry, had recently joined the aquarium and was dismayed that the staff did not have a better plan for handling the situation. "I remember thinking, 'There's got to be a better way,' " he said.

About 15 years ago, Monterey biologists learned that researchers in Waikiki, Hawaii, had managed to sustain a hammerhead shark in captivity temporarily by keeping it first in a lagoon before moving it to an aquarium tank. After consulting with several other California shark experts, Monterey Bay's staff rented an ocean pen 35 feet deep and 135 feet in diameter to house any great white shark they captured, at least at first.

With the pen ready, aquarium scientists notified Southern California fishermen in 2002 that they were looking for a shark that either came close to shore or was caught inadvertently, but none materialized. The following year they did find one, but they had to return the pen to its owner before the shark was fully acclimated.

In 2004 they finally succeeded, putting a female shark, which had been caught in a net, in an ocean pen and then bringing it to the aquarium in a 3,000-gallon "Tunabego" tank that had been used in the past to transport tuna.

That shark stayed on display for 6 1/2 months and attracted nearly a million visitors, until it started attacking other sharks housed in the same tank. Officials released it in March 2005 after attaching a satellite-transmitting tag to its dorsal fin. The tag was made to pop off a month later, allowing researchers to confirm that the shark had thrived after being set free.

Monterey biologists are teaming up with scientists at Stanford University's Hopkins Marine Station, whose offices adjoin the aquarium, to study juvenile sharks. Marine sciences professor Barbara Block, the chief scientist of Tagging of Pacific Pelagics, a 50-member research project monitoring predators in the North Pacific, has pioneered attaching satellite tags to sharks to track their movements in detail.

In recent years, scientists have learned that California's great whites can travel as far away as Hawaii during the winter, though they return each year to their feeding grounds.

The researchers are studying the young great white's movements in the tank through video, as well as analyzing how it metabolizes its food.

The program is a massive undertaking: Monterey Bay officials estimate they have spent nearly $4 million on the shark project so far, with $840,000 devoted to field conservation research. The aquarium credits 40 individuals with helping to bring in their most recent juvenile, and about five staffers care for it daily.

Most great white pups caught in California turn up within a 20-mile radius of Long Beach, so both the California State University at Long Beach Shark Lab and the Southern California Marine Institute help monitor shark catches.

"We're the rapid-response team," said Christopher Lowe, who directs the Shark Lab and dispatches his students to meet fishermen who have secured great whites nearby. "It's location, location, location."

A few detractors have questioned whether it is wise to put on display an open-ocean predator that can travel thousands of miles in a year. Sean Van Sommeran, executive director of the Pelagic Shark Research Foundation in Santa Cruz, criticized the aquarium after observing that its first captive great white had abrasions on its snout. John O'Sullivan, the aquarium's curator of field operations, said the injury occurred when the shark was tangled in the fishing net; Van Sommeran said it stemmed from the shark's rubbing up against the exhibit's tank.

"Certain species of pelagics don't do well in captivity and don't do well in captive exhibits," Van Sommeran said, adding that he respects the aquarium's researchers.

The aquarium's latest great white appears to be thriving, eating roughly three pounds of salmon and mackerel a day. O'Sullivan sees his job as "halfway through" at this point, since he is waiting to see if the juvenile does well after it is released. "I'm not happy until that tag comes off and we know that animal has survived."

The toothy predator doesn't have a nickname: O'Sullivan frowns upon it. "These animals are wild, and they're going to return to the wild," he said. "Naming them gives the impression that they're pets."

In the meantime, however, the tourists are continuing to gawk at a species that author Herman Melville described as more terrifying than a "fierce-fanged tiger." In the past seven weeks 250,000 visitors have come to see it, many of them drawn by a fearsome reputation that goes back at least as far as Melville's "Moby Dick."

"Witness the white bear of the poles, and the white shark of the tropics; what but their smooth, flaky whiteness makes them the transcendent horrors they are?" Melville wrote in 1851.

But after seeing the Monterey Bay Aquarium's exhibit half a dozen times, neither Trenton Wheeler nor his sister Alyssa fears great whites anymore. Alyssa, a bubbly 10-year-old, offered an entirely reasonable explanation for her sangfroid: "You shouldn't be scared of them. Only the ones that are really, really big eat people."


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