Great White sharks tagged on Guadalupe Island

Is this science, or is this a TV show?

In late 2007, when local shark researcher Michael Domeier teamed up with a television crew and National Geographic to tag great white sharks off Guadalupe Island, Patric Douglas took an interest. Douglas runs a cage-diving tourist operation out of San Diego. Each fall he takes his clients to the island, 250 miles southwest of Ensenada, 150 miles off the coast. He also works with movie and TV production companies that are filming sharks. Douglas has supported several shark-research projects, including Domeier’s.

But when Douglas learned that Fischer Productions — an outdoor adventure film company based in Park City, Utah — was funding the expedition, providing the vessel, and bringing Hollywood actor Paul Walker, star of The Fast and the Furious, on board, he lost faith in the project.

“Is this science, or is this a TV show with some science thrown in?” asks Douglas.

Domeier, founder and executive director of the Marine Conservation Science Institute in Fallbrook, has been studying great white sharks for almost a decade. From 2000 to 2007, he tagged the animals at Guadalupe Island using a handheld tagging pole — a common technique — but late in 2007 he began deploying advanced Spot (Smart Position or Temperature Transmitting) tags onto the fish. Spot-tagging involves catching the fish on a baited hook, lifting the shark onto a vessel, and bolting a transmitter to its dorsal fin. Every time the tagged shark surfaces, allowing the device to touch the air, the Spot tag sends a signal to a satellite. The satellite, in turn, instantly emails researchers, providing real-time information on individual shark movement. Spot tags may last years longer than other transmitters, making them valuable research tools. Scientists have deployed them onto smaller fish, including salmon sharks and hammerheads of several hundred pounds.

However, the stress imparted to an animal during tagging is a drawback, and the larger the animal, the greater the potential for stress-related injuries. It can take an hour or more to reel in a large white shark, which may weigh more than two tons. Then the shark may spend 20 minutes out of the water, a hose placed inside its mouth to hydrate its gills with fresh seawater. Douglas is concerned that Domeier’s research could injure or kill the fish, and he is suspicious of Domeier’s relationship with a camera crew.

“It’s not uncommon for a TV show to donate money to a researcher and then tag along and watch the scientist do his thing,” says Douglas. “But what’s morally suspect and ethically suspect about Domeier’s project is that Fischer Productions is running this show.”

On November 16, National Geographic aired the first of 11 television episodes featuring Domeier, Walker, and other crew members as they placed large circle hooks baited with mammal flesh into the waters of the Guadalupe Island Biosphere Reserve, caught several great white sharks, and bolted Spot tags into their dorsal fins. Chris Moore, line producer for Fischer Productions, says that the entire first season has been filmed, with ten episodes scheduled to air beginning in July 2010.

By fall of this year, Domeier had placed 15 Spot tags on Guadalupe Island white sharks. Then, in late October, the team traveled north to the Farallon Islands, off San Francisco, with permission from federal and state authorities to catch and tag as many as ten of the otherwise-protected sharks in the waters of the Gulf of the Farallones National Marine Sanctuary.

But on October 29, the team botched its first catch when a 13-foot great white shark swallowed the bait and, after almost an hour on the line and roughly 20 minutes on board the boat, could only be released after the crew clipped the hook via bolt cutters inserted through one of the shark’s gill slits. The shark eventually swam away with a portion of a large circle hook lodged in its throat. Domeier landed and tagged a second shark three days later before agents with the National Oceanic and Atmospheric Administration halted the project.

Douglas believes the health of the first shark has been compromised.

“I don’t think you can leave 60 percent of the world’s largest circle hook in the gut of a shark and know that [the shark] is safe. The future of that animal is now in grave doubt.”

Dr. Ken Goldman, a fisheries biologist with the Alaska Department of Fish and Game, has tagged sharks off Northern California. He also believes white sharks may be injured by Spot-tagging.

“There’s a chance of the animal being decked and suffering organ damage, and it could easily rupture its liver and you wouldn’t know,” he says.

Goldman once saw a white shark off the coast of South Australia, recently caught and released, in a near-death state of exhaustion. His foremost concern about Domeier’s research is that Spot-tagged sharks may swim away from the operation exhausted, unable to maintain basic vascular functions, and as a result experience a steep decline in body temperature, which averages a stable 74 degrees Fahrenheit in white sharks, according to Goldman.

“And if a white shark can’t maintain that core temperature, it dies,” he says.

Late last month, Domeier was back at Guadalupe Island with cameras rolling. Fischer Productions and Domeier are tagging more sharks and compiling new footage with the hope of producing a second season in 2011, says line producer Chris Moore.

Domeier maintains that Spot tags will add substantially to the work he and others have already conducted with simpler forms of devices. In late November, he explained via email that he suspects that the Guadalupe great whites may move through the Pacific on a two-year migratory cycle — a time period that only Spot tags can reliably record, he said.

“Effective international white shark conservation requires us to find out where these mature females are spending their time when they do not return to the adult aggregation sites,” he wrote. “We cannot understand the threats they face without knowing precisely where they are during this time. The Spot tagging methods I have developed will allow us to track individuals for up to 6 years.”

Domeier asserts that all white sharks he has Spot-tagged have been proven to be alive after the procedure, each animal generating the satellite pings indicative of a live, swimming shark.

“The level of temporary stress we subject these fish to is unfortunate, but the scientific advancements are well worth the effort,” he wrote by email. “Our tracking data has proven these sharks quickly resume their normal behavior.”

During Domeier’s earlier white shark research at Guadalupe Island, he tagged 75 animals using handheld tagging poles. The satellite tags released from the sharks between 15 and 246 days after deployment, and 9 devices were later recovered, providing data on white shark migratory behavior. At least five of the tagged animals had swum as far west as Hawaii before returning to the Mexican island, and when Domeier and coauthor Nicole Lucas published their findings in October 2008 in the Marine Ecology Progress Series, they added substantially to the amassing scientific knowledge of the life habits and movement patterns of white sharks.

Scientists have been tracking great white sharks for years. A group called Tagging of Pacific Predators, based in Northern California, put transmitters into 179 Northern California great white sharks between 2000 and 2008 and in November published findings on the migratory patterns of the fish. Sean Van Sommeran, founder of the Pelagic Shark Research Foundation in Santa Cruz, has inserted approximately 50 identification tags and transmitters into white sharks using handheld tagging poles as they swam past his boat.

“We’ve been tagging them by hand from a boat for 15 years,” says Van Sommeran. “It’s the best way. It’s less invasive, doesn’t stress the animal, and has produced an avalanche of data. We barely touch the sharks.”

Goldman, the fisheries biologist with the Alaska Department of Fish and Game, conducted transmitter research on white sharks in the 1990s at the Farallon Islands.

“I really wonder how much more information they can get off the Spot tags than from the other kinds of satellite tags already in use that don’t require lifting this heavy fish from the water,” he says.

Mike Lever is, like Douglas, a cage-diving guide, whose vessel, Nautilus Explorer, is based in Ensenada. In 2008, Lever donated $14,000 to Domeier’s work, hoping to assist in understanding the species upon which his livelihood depends. But Lever also has doubts about the safety of white sharks undergoing Spot-tagging.

“I believe in pricking a shark with a spear and receiving tracking data for years afterward, but do we need to be hauling sharks onto boats for the same goal?” says Lever. “The big question is, Are the sharks okay afterward?”

Domeier contends that his work has been criticized unfairly, as other researchers have Spot-tagged large animals. Researchers have placed Spot tags on 400-pound salmon sharks. University of California at Davis biologists have Spot-tagged eight-foot-long hammerheads at the Galapagos. And the Tag-A-Giant Foundation, based in New York, has deployed dozens of pop-off tags onto half-ton bluefin tuna, caught on rod and reel and lifted onto the deck of a vessel.

“These very same colleagues use the exact same methods as I on other species that have similar conservation status, but for some reason it is OK,” Domeier wrote by email.

Even before Domeier began his current research, Spot-tagging had a cloudy history at Guadalupe Island. In 2006, an independent researcher, Dr. Ramón Bonfil, pulled a white shark from the water and placed a Spot tag on the animal as part of another National Geographic film project. The shark, a 16-foot female well known to the Guadalupe Island cage-diving community and nicknamed “Clytie,” has not been seen since.

Other researchers currently study great white sharks at the island. Dr. Mauricio Hoyos, an independently funded biologist from La Paz, is tracking the local movements of Guadalupe Island white sharks via acoustic tags, which are deployed with a simple stab at the dorsal muscles with a handheld lance and which emit a signal each time a tagged shark passes near a subsurface receiver. The data provided by such tags is limited — a presence or absence of the animal. Hoyos could not be reached for comment, but a field assistant, UC Davis biotelemetry grad student James Ketchum, acknowledged the great value of tracking animals across the ocean via Spot tags.

“But I don’t think they need to lift the shark out of the water,” says Ketchum, who believes Spot-tagging could cause internal injuries. “I think they could keep the shark in the water in a sling as they bolt in the tag, but what they’re doing is very sensationalist. It’s something that sells.”

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