Researchers tracking tiger sharks in Hawaii after spate of attacks

WAILUKU, Hawaii, Nov. 24 (UPI) -- In 2012, there were eight reported shark attacks off the beaches of Hawaii. In 2013, there were another eight. Two of the 16 were fatal. In the fall of 2013, scientists began tagging and tracking tiger sharks to try ascertain a change in behavior that might explain the uptick in unprovoked attacks.

Researchers at the University of Hawaii's Institute of Marine Biology tagged 24 tiger sharks in October 2013. Several more were tagged at the beginning of 2014. Currently, satellites help marine biologists working on the shark-tracking program keep tabs on some 35 specimens.

So far, their tracked movements, scientists say, haven't offered new insights into the sharks behavior.

"We are seeing the exact same depth preferences around O'ahu, but the most frequently used sites don't line up with popular swimming and surfing sites to the extent that they do around Maui," Kim Holland, a shark expert and marine biologist at the University of Hawaii, explained in the press statement. "Both O'ahu and Maui have high levels of recreational ocean use, yet Maui has a higher rate of shark bites. We are trying to determine why."

So far in 2014, there have been five reported shark bites, none of them fatal.

"We need to understand tiger shark movements in our coastal waters to gain a clearer comprehension of the circumstances bringing sharks and humans together," Holland added.

Holland and his colleagues say one of the reasons many tiger sharks congregate around the Maui islands is that the area posses of a plethora of its preferred mating habitat. Tiger sharks prefer water running from the shallows to an offshore depth of 600 feet. Maui offers a coastal shelf that runs for 10 miles before dropping off deeper than 600 feet.

Researchers will continue tracking and analyzing the sharks' behaviors through the end of the year.