Hammerhead Shark Superhighway

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A scientist hoping to save hammerhead sharks from extinction is leading a team of researchers who are tracking the fish underwater, hoping to prove the existence of a shark superhighway.

These unusual creatures, known for their oddly shaped heads that aid in navigating and finding food, were once plentiful in the world’s oceans. Today their numbers have been decimated by fishermen.

For the past three decades Dr. Peter Klimley, a marine biologist at the University of California-Davis, has been studying hammerheads in the Pacific Ocean. He is now determined to discover their superhighway, a distinct route that he believes they travel within a network of favored destinations. If he can prove the route exists, he says, he can work to protect it.

“I think their taking the highways connecting these islands is an essential part of their conservation,” Klimley said.

Klimley’s team has embarked on the complicated task of outfitting a group of hammerhead sharks with high-tech tracking devices.

“Each device has a train of beeps that is unique to this tag, and that way we can follow the shark as it moves around the island, or follow it as it moves between islands,” Klimley said.

The tracking devices on 100 sharks quickly showed that they are sticking together.

Many of the sharks were moving between Wolf and Darwin Islands in the Galapagos, about 25 miles apart. But one female shark took a 600 mile journey to the Cocos Islands near Costa Rica, then returned to the Galapagos.

The islands are connected by an undersea ridge, a feature that Klimley thinks the sharks might be using to navigate.

If he and his team can prove that this is the shark superhighway, thousands of sharks can be saved. To do it, they’ll need to track the sharks with more sophisticated satellite equipment. But it won’t be easy.

“Hammerheads in general tend to be particularly delicate sharks,” he said.

Capturing and tagging an adult hammerhead is incredibly difficult because these sharks must always be swimming forward in order to keep oxygenated water moving over their gills; otherwise they will quickly suffocate and die.

Scientists estimate they have five minutes or less to make it happen.

The crew inserts a water hose into the shark’s mouth, but it’s only a temporary lifeline and a race against time to attach the tracking device to its dorsal fin.

Source: abcnews