Feb 28, 2011 12:29 GMT  ·  By
Hammerhead sharks are threatened with extinction worldwide due to overfishing
   Hammerhead sharks are threatened with extinction worldwide due to overfishing

For the first time ever, a group of scientists was able to monitor the migration pattern of large hammerhead sharks, by using advanced tags that could be traced from Earth's orbit. These beautiful animals were kept under observation for a total of about 62 days.

They traveled roughly from the coast of South Florida to the middle of the Atlantic Ocean, off the coast of New Jersey, says the research team. The experts are based at the University of Miami (UM) Rosenstiel School of Marine & Atmospheric Science.

In total, the animal the team surveyed traveled in excess of 1,200 kilometers (745 miles), which represents a larger distance than usually associated with this species' migration patterns.

In addition, the team in charge of the investigation learned that the sharks used the Gulf Stream current for their own benefit, and also that they navigated the open waters of the northwestern Atlantic Ocean.

Rosenstiel School research assistant professor Neil Hammershlag was the leader of the study, which also involved several of his colleagues. “This animal made an extraordinary large movement in a short amount of time,” he says.

“This single observation is a starting point, it shows we need to expand our efforts to learn more about them,” adds the expert, who is also the director of the R.J. Dunlap Marine Conservation Program at the UM Rosenstiel School.

He and other study authors explain in a new paper that the animal was most likely following its food sources, which include mahi-mahi and jacks. As such, it traveled away from the continental slope, and into the Gulf Stream current.

Hammerschlag says that the new research is important because it's part of a larger effort. The research is focused on locating the feeding, mating, and pupping areas that these sharks use regularly .

“This study provides evidence that great hammerheads can migrate into international waters, where these sharks are vulnerable to illegal fishing,” the team leader explains.

“By knowing the areas where they are vulnerable to exploitation we can help generate information useful for conservation and management of this species,” he goes on to say.

The International Union for Conservation of Nature (ICUN) classifies great hammerhead sharks in the northwest Atlantic and the Gulf of Mexico as endangered. Worldwide, they are threatened with extinction due to overfishing and accidental bycatch.

Details of the new study appear in a paper called “Range extension of the Endangered great hammerhead shark Sphyrna mokarran in the Northwest Atlantic: preliminary data and significance for conservation.

The work was published in the latest issue of the esteemed journal Endangered Species Research, Science Blog reports.