The science of sharks: More than ‘mindless eating machines’

By Waldy Diez (USA Today) – Despite at least two dozen shark attacks this year making major headlines, sharks are not out to get you, experts say.

“They are not the indiscriminate eating machines that they were once made out to be,” said diver Holly Bourbon, curator of large-fish exhibits and dive safety officer at the National Aquarium in Baltimore.

People are more likely to be injured by car accidents, falling, and lightning, according to the International Shark Attack File at the Florida Museum of Natural History at theUniversity of Florida.

“They are actually intelligent animals who can be trained,” she said.

Bourbon said significant research has been done on sharks, but there is still room to grow.

“There are so many sharks, it’s hard to know everything about all of them,” she said. “We’re still learning about them as time goes on.”

A few of the biggest mysteries about sharks are their mating and migratory habits, said the founding chairman of OCEARCH, a nonprofit that specializes in the research of great white sharks and other top-of-the-food-chain predators.

Chris Fischer said sharks’ ability to be trained helps in shark “tagging,” or attaching GPS trackers to the animals’ fins. The animals are trained to come to the cages used in diving expeditions, and tagging allows researchers to track sharks for up to five years.

Fischer said he and his team have “cracked the code” when it comes to tagging and tracking. He said they could catch a 4,000-pound shark in about 40 minutes and a 1,000-pound shark in about 10 minutes.

The GPS tag on Mary Lee's fin will allow OCEARCH to track the shark. (Photo: OCEARCH)
The GPS tag on Mary Lee’s fin will allow OCEARCH to track the shark. (Photo: OCEARCH)

Once caught, the OCEARCH team has a limited amount of time to do its initial research. In a matter of 15 minutes, “we’ll conduct 12 research projects,” Fischer said. “We’ll get the first live blood-draws of those sharks in history,” as well as tissue and parasite samples.

OCEARCH then shares its data with any research institution that’s interested, says Fischer, who says he encourages researchers to attend expeditions.

OCEARCH has conducted 22 expeditions since it was founded in 2007. It combines fishermen and scientists with funding from businesses, including Caterpillar, Costa andYamaha.

“You got really this kind of three-party enterprise,” Fischer said. “You got the practical world of the fishermen, the academic world of the world-class scientists, and the financial stability of the socially innovative company funding it all.”

Expeditions have helped OCEARCH advance shark research, including information about the massive migratory ranges of sharks. Researchers learned that females migrate for two to three years, and males migrate every year. One shark even migrated 35,000 miles, up and down the Atlantic coast from Canada to Cuba and all through the Atlantic, halfway to Europe in two and a half years, Fischer said.

Lydia, a mature great white shark, has traveled 35,028 miles since being tagged in March 2013. (Photo: OCEARCH)
Lydia, a mature great white shark, has traveled 35,028 miles since being tagged in March 2013. (Photo: OCEARCH)

He said the team has discovered the first known great-white birthing place at Guadalupe Island off the west coast of the Baja Peninsula. OCEARCH found adult males visited this site every year, whereas reproductively active females visited every two years. The team found this migratory pattern matched with a shark’s 18-month gestation period. He said this is crucial; according to the International Union for Conservation of Nature, 15% of sharks are endangered.

Finding mating and birthing places could help raise the overall shark population, Fischer said.

Sharks are the “balance keepers” of the ocean, Fischer said. They keep the seal and secondary predator populations down. This helps keep more fish in the ocean, ensuring the food chain stays intact.

“We are going to win the shark battle in our lives,” Fischer said. “We will see them return to abundance. Then, we will move on to the next problems we need to solve for the ocean.”

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