Thursday, November 19, 2009

Is scientist using "inhumane" tagging methods on Great White sharks?

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Were you able to watch the National Geographic special, "White Shark Expedition," on Monday night -- and if so, what do you think of the methods utilized by researcher Michael Domeier at remote Guadalupe Island off Baja California?

If you live in the Bay Area, you might also have viewed an ABC News program that was spawned by an incident involving Domeier's team using the same methods at the Farallon Islands off San Francisco. The program featured experts who were critical of the methods, which involve using a team of anglers and a large baited hook attached to a line with buoys.

(There's also a film crew, hence the National Geographic special and related episodes to air next summer.)

The hooked shark struggles until it's completely worn out. It's then lifted onto a platform, where a sophisticated tracking tag is bolted into its dorsal fin. A large hose is used to flush water through the shark's gills, so it can breathe throughout a process that can take 20 minutes.

The sharks usually are hooked in the corner of the mouth -- because of the 24-inch circle hook's design --but in at least one case at the Farallon Islands a shark had to be set free with part of the hook lodged deep in its throat.

The specialized tags have a life span of up to six years, providing real-time data and pinpointing precise locations of migrating sharks. They're important, Domeier says, for researchers seeking a clearer picture of these mysterious predators' life history.

I watched both programs and from a non-scientist's viewpoint (mine) the methods appear overly intrusive and harmful to a species of shark that is protected by federal law in the U.S. Given the extent of research already underway on white sharks by renowned scientists at the Farallones, I was surprised to learn that Domeier had even been granted access to the Gulf of the Farallones National Marine Sanctuary.

Said sanctuary superintendent Maria Brown on the ABC News program: "This research helps us protect white sharks. I equated it to ... it felt like what it's like when I go to the dentist; when you go in, you get a cavity filled. It's something that maybe you don't want to go do, but you do it, it's quick, it's over, it's done."

It's not that quick; it involves a giant hook and tiring the predators to the extent they can no longer struggle. Besides, experts from various universities have already learned where these sharks go when they leave the islands -- to a vast, featureless area in the mid-Pacific, and some venture beyond Hawaii. Why they go and what they do there, however, remains unclear.

Like ABC News, I talked to Peter Klimley, a UC Davis professor and one of the world's leading shark researchers. He's against Domeier's methods and called them unnecessary. He said lifting so large a creature from the water Is potentially harmful. He added that pregnant females might be especially vulnerable to the technique. Klimley also expressed concern about how other scientists might be perceived by viewers of the National Geographic special.

"For the most part we are compassionate and we do care about how we handle the animals we work with," he said.

Domeier, president of the Marine Conservation Science Institute, defended his methods and said, via e-mail: "I can unequivocally say that we have tagged and released 17 white sharks in the past two years and every single one has survived. The decision to use these tags was not trivial; the data we obtain from them can be gathered no other way, and the resulting multi-year tracks are going to reveal life history characteristics that will rewrite white shark life history."

Domeier also defended using a team of fishermen headed by big-game angler Chris Fischer, who runs Fischer Productions, and an actor that accompanied the group to Guadalupe Island.

"The reality is this: Without the involvement of the media on this project there would be no project," Domeier said. "The research is hugely expensive and the only way to pay for it is to involve National Geographic and Fischer Productions."

-- Pete Thomas

Photo: Crew member Chad Kiesel, left, and angler Chris Fischer tag a 14-foot female great white shark at Guadalupe Island. The hydration hose in the shark's mouth is designed to keep the predator alive while the team measures and tags it and takes blood samples. Credit: Chris Ross / National Geographic Channel

Huge Great White shark caught off Guadalupe Island

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"Expedition Great White" airs tonight at 9 p.m. on the National Geographic Channel, and if the accompanying photo is an indication, the footage ought to be spectacular.

The location is Guadalupe Island, 160 miles west of Baja California, a truly spectacular destination and one of the world's largest seasonal gathering places for adult great white sharks. That's where researcher Michael Domeier has been studying the apex predators, and using satellite tags to determine their migration patterns and other habits.

And it's where TV fishing personality Chris Fischer got to play the role of angler -- and literally come face to face with a 4,600-pound white shark -- during a monumental capture aboard his 126-foot mothership, named Ocean.

"Like in the movie 'Jaws,' the first time we saw a shark come in and eat the bait and then take off and drag the buoys under and across the water it was a life-changing moment as an angler," Fischer said. "The experience of capturing and releasing giant great white sharks is nothing similar to an angling experience of capturing large pelagic fish. There's a sense of history, a sense of awe, humility and humbleness."

Domeier is a legitimate researcher, but some might question the methods: hooking and hoisting incredibly large sharks from the water -- even if for only brief periods and if great care is utilized -- for tagging, measuring and DNA sampling.

Domeier, however, assures that great care is utilized and that "this is a show about real science ... not science created for TV, which is so often the case."

Tonight's episode is part of a longer series that will air next summer and undoubtedly will shed significant light on the lifestyle of one of the world's most notorious and mysterious predators.

-- Pete Thomas

Photo: Crew member Jody Whitworth lifts the snout of a great white shark as Capt. Brett McBride removes hydration hose that keeps the predator alive while it's on deck. Credit: National Geographic Channel / Chris Ross

Woman fights off Great White shark!

An Australian woman has survived an attack by a Great White shark by beating it with a paddle after it knocked her off a surf ski.

Linda Whitehurst, the shark's intended victim, said: "I thought this is it, he is going to grab my leg. I had my blade (paddle) and I just kept punching, punching, punching."

She suffered only small lacerations on her right arm in the fight with the 8ft-long shark.

She then managed to scrambling back onto her surf ski and paddling to shore at Byron Bay's famous surfing beach, "The Pass", on Australia's east coast.

Sunday, November 15, 2009

A 3m Great White shark was the victim of a...shark attack!

Concerns were raised after a 3 m great white shark was found dead with two huge bites taken out of its body. Experts believe the bites were made by an even larger predatory fish.

Swimmers have been warned to stay out of the waters off Stradbroke Island, north of Brisbane.

“It certainly opened up my eyes. I mean the shark that was caught is a substantial shark in itself,” Jeff Krause of Queensland Fisheries told the Sydney Daily Telegraph.

Surfers have reacted to the news of the shark attack with shock.

“Whatever attacked and took chunks out of this big shark must be massive,” said Ashton Smith, 19. “I’ve heard about the big one that’s lurking out there somewhere.

Saturday, November 14, 2009

Researchers share their findings about the migratory patterns of Great White sharks

Stanford scientists are learning a great deal about great white sharks.

Scientists at the Hopkins Marine Station have concluded that great white sharks, like salmon, have a specific migratory pattern. Their research, published in the scientific journal Proceedings of the Royal Society B on Nov. 4, also found that Pacific white sharks, genetically distinct from other great whites, are swimming in the San Francisco Bay.

Prof. Barbara Block, who facilitated and co-authored the study in collaboration with scientists from UC-Davis, among others, compared the decade-long observation of great whites in the Pacific Ocean to studies of lions and tigers in Africa.

“We’re doing [the study] on the largest ocean in the planet – it was a tall task,” Block said. She and other marine scientists tagged a total of 179 great white sharks using Pop Up Satellite Archival Tags (PATs) and monitored their swimming in the Pacific.

The PATs, according to doctoral student in biology, field project leader and co-author Chris Perle, allowed for the sharks to be tracked via satellite. Perle, who helped attach approximately 20 tags to the sharks, explained in an e-mail to The Daily that each tag is pre-programmed to “pop-off” the shark and send data back for analysis. The sharks’ travel is then measured by the light and sea surface temperature data.

Researchers found that great white sharks travel from the central California coast out into the open ocean to Hawai’i and a nearby popular location dubbed the “White Shark Café.”

“What we learned the most about the white sharks was that they were making round trips – 4,000 nautical mile trips,” Block said. “But they were coming back with precision to the place we let them go.”

In an e-mail to The Daily, Bing Director in Human Biology Carol Boggs said the research offered a clearer conception of the relationship of sharks to their environment.

“It is cool that we’re discovering that large marine organisms behave more like what we’re used to thinking of as standard for large terrestrial animals, with defined geography for the population, and even something resembling individual ‘home ranges,’” Boggs said.

“This blows the idea out of the water that the ocean is a vast, trackless melting pot,” she added.

Great white sharks leave from “hot spots” on the shore around where sea lions and elephant seals gather to feed. Using additional acoustic tags acting as a microchip that can be transmitted from 300 meters away, the sharks’ shore movements were tracked by receivers sunk at the bottom of the ocean.

“We call it ‘homing infidelity,’” Block added. “Just like a salmon going up the stream, we didn’t know white sharks had a home spot.”

According to postdoctoral fellow and co-author Salvador Jorgensen, scientists were already familiar with the fact that white sharks migrate. The main discovery is the consistency in these migratory routes, which Jorgensen called “a virtual highway,” and that the sharks did not venture on to other areas of the Pacific.

“This was further confirmed with genetics data based on maternally inherited mtDNA markers, suggesting that we are looking at a distinct population that is demographically isolated from other known populations of white sharks in the Indo-Pacific (i.e. South Africa and Australia/New Zealand),” Jorgensen wrote in an e-mail to The Daily.

Geneticist Carol Reeb, a research associate in biology and co-author, also determined that Pacific white sharks are genetically distinct within their species. She found the difference by comparing a previous study of great white shark genetic sequences from South Africa and New Zealand with the data Jorgensen collected.

The population of white sharks off of the California coast has a 200,000 year-old ancestry with Australian sharks, migrating during the Pleistocene epoch period at the same time humans migrated out of Africa.

“[The Pacific white sharks] didn’t really go anywhere else which was interesting because these are highly migratory animals and they have the potential to go anywhere in theory,” Reeb said.

Male sharks were previously considered to be free-roaming. Conversely, female sharks, according to Reeb, are known to be philopatric, meaning they return to their original birthplaces. This study refutes the original behavioral predictions and confirms a pattern among both sexes.

Reeb is currently working on a similar study with Mexican sharks to determine if they display distinct behaviors and potentially different genes as well. Boggs, who works in population dynamics, finds the potential for further species conservation in this genetic discovery.

“The result that the ‘local’ population is genetically distinct, with a very old separation date from other populations of the same species, is both interesting and surprising,” Boggs said. “It indicates that these sharks may be adapted to the environment of the northeastern Pacific, which has implications for conservation efforts.”

The tracking devices made an additional observation that many found to be more surprising. Great white sharks were detected swimming as far in the San Francisco Bay as the Golden Gate Bridge. However, many of the scientists working on the study were not at all astonished with this finding.

“We learned this only because a row of sensors set up by our colleagues to detect salmon migrations was compatible with our tags,” Jorgensen wrote. “So it was unanticipated but not entirely surprising.”

Five out of 75 great white sharks were detected up to one mile inside the Bay, chalking up to 0.07 percent of the total tag detections in the study.

Saturday, November 07, 2009

Surfer attacked by Great White shark

Last night, during a freesurf session at Lagunas (north of Santa Cruz, where the O'Neill Cold Water Classic is happening right now), pro surfer Eric Geiselman was struck by what is believed to be a great white shark.

Apparently his board was immediately snapped in half but luckily the surfer escaped with no harm. Check out more info about the terrifying incident and some words from the man himself on the link below:

Eric Geiselman Gets Attacked by Shark

Great White sharks spotted on Oregon Coast

Why are we hearing about great white shark sightings off the Oregon coast?

One was even spotted in three feet of water. And surfers tell KATU News the sharks are coming right up to the surf line. One, believed to be 16 to 18 feet long, swam right between short boarders at South Beach State Park, just outside of Newport.

So what's going on? Why are they here?

One reason for the increase is because the water is warm right now, so the great white is here to feed. And scientists expect their numbers have probably grown since they've been federally protected from being killed since the 1970s.

Then there's the fact that there are more people out in the water off the Oregon coast than ever before.

Shark researchers say great white sharks are more curious than anything when it comes to people in the water. It is believed, however, that they will mistake a surfer sitting on a surfboard for a sea lion and that's when the Great Whites will sometimes go in for a bite.

You often hear how a person was bitten by a shark and then it swam away. Researchers don't know if that's because the shark got a taste of a person and didn't like the flavor or if they're trying to let their prey lose strength before they go back for more.

Monterey Bay Aquarium released another Great White shark

A great white shark was released back into the wild at Monterey Bay on Wednesday after spending nearly three months at the Monterey Bay Aquarium.The release marks the fifth time the aquarium has successfully exhibited and released a great white shark.
Monterey Bay Aquarium
Aquarium staff released the young, female shark in offshore waters near the southern tip of Monterey Bay just after sunrise.The shark had been collected on Aug. 12 near Malibu after it got caught in fishing nets.Images: Great White Shark Released Into WildIn 50 years of attempts worldwide, the Monterey Bay Aquarium remains the only institution to have a great white shark on exhibit for more than 16 days and then successfully return the animal to the ocean.“I’ve always said that these animals will tell us when it’s time to put them back to the ocean. Now was clearly the time,” said Randy Hamilton, vice president of husbandry for the aquarium. “Her health is excellent, and we learned a lot while she was with us. Based on past experience, we have every expectation that she’ll do well after release.”The shark grew from 5 feet 3 inches and just under 80 pounds to 5 feet 5 inches and 100 pounds during its time on exhibit at the aquarium.During Halloween weekend, the shark received a bite wound and was observed chasing scalloped hammerhead sharks in the exhibit. A Galapagos shark was bitten and injured by the great white, Hamilton said. “We monitor the behavior of great white sharks very closely while they’re on exhibit,” he said. “When we saw a new pattern of aggressive behavior, we decided it was best to release her.”The exhibit of great white sharks at the aquarium is part of an effort to raise awareness and change attitudes toward the ocean predators, aquarium officials said.

Northeastern Pacific Ocean: Isolated migrations of Great White sharks have been discovered

In a new research, scientists have found that the migratory behaviors of the white shark has lead to the formation of isolated populations in the northeastern Pacific Ocean that are genetically distinct from sharks elsewhere in the world.

White sharks are a large, highly mobile species, said Salvador Jorgensen, a postdoctoral scholar at Stanfords Hopkins Marine Station.

They can go just about anywhere they want in the ocean, so its really surprising that their migratory behaviors lead to the formation of isolatedpopulations, he added.

Scientists with the Tagging of Pacific Predators (TOPP) program combined satellite tagging, passive acoustic monitoring and genetic tags to studywhite sharks popularly known as great white sharks in the North Pacific.

The researchers used a combination of satellite and acoustic tags to follow the migrations of 179 individual white sharks between 2000 and 2008.

These sharks were adults or sub-adults that ranged in size up to 4,000 pounds, and were individually tagged at sites along the central California coast, including the Gulf of the Farallones, Tomales Bay and Ano Nuevo.

The electronic tags reveal that the sharks spend the majority of their time in three areas of the Pacific: the North American shelf waters of California; the slope and offshore waters around Hawaii; and an area calledthe White Shark Caf, located in the open ocean approximately halfway between the Baja Peninsula and the Hawaiian Islands.

The research team placed acoustic listening receivers on the ocean floor at sites thought to be high residency areas, or hot spots.

By attaching 78 acoustic tags that create a unique ping or acoustic code for each tagged shark, the researchers were able to detect when thewhite sharks came within 250 meters (820 feet) of a receiver.

This allowed the researchers to discern their pattern of coastal movements in high detail.

The tags revealed that often sharks had favorite sites where they would remain resident for up to 107 days, although they occasionally would make brief visits to the other nearshore hot spots.

Also, genetics techniques were used to examine the relationships of the California sharks to all other white sharks examined globally.

Studies of maternally inherited mitochondrial DNA sequences show that the populations are distinct, and suggest that the northeastern Pacific population may have been founded by a relatively small number of sharks in the late Pleistocene within the last 200,000 years or so.

According to Molecular geneticist Carol Reeb, a research associate at Stanford, Even though we know they travel great distances, their paths are surprisingly constrained to specific routes. This explains how a highly migratory marine species becomes a genetically isolated population.