Despite the minuscule numbers of people killed every year by sharks (and massive numbers of sharks killed by humans each year), there’s something about the creatures that terrifies many visitors to Hawaii. For Hawaii’s native kanaka maoli, this is unfortunate, given that to them sharks are ‘aumakua, the reborn spirits of deceased ancestors who serve now as guardians.
For marine biologists, sharks are neither benevolent spirits nor dangerous monsters–they’re mysteries, deserving of studied, careful research. Following a cluster of shark bite incidents in 2012, two internationally recognized shark experts began tagging tiger sharks in the waters around Maui and Oahu in hopes of learning more about the creatures.
In 2013, “24 large tiger sharks were captured and fitted with tracking devices off Kihei, Olowalu and Kahului, Maui,” stated a Nov. 20 news release from the University of Hawaii. “The tagging efforts are providing new insights into the coastal habitats most frequently visited by tiger sharks around Maui.”
Now the data is coming in. According to the researchers, tiger sharks really prefer shallower waters.
“We are seeing a strong preference for coastal shelf habitats shallower than 600 ft,” said Dr. Carl Meyer, who’s with the Hawai‘i Institute of Marine Biology, in the Nov. 20 UH news release. “Although these sharks also roam far out into the open-ocean, they are most frequently detected in the area between the coast and the 600 ft depth contour which is up to 10 miles offshore around Maui.”
What’s even more fascinating is that the sharks seem to behave differently around each island.
“We are tracking tiger sharks around O‘ahu and Maui simultaneously so that we can have the clearest possible comparison of tiger shark behavior between these two islands,” said Dr. Kim Holland, UH’s senior shark scientist, in the Nov. 20 UH news release. “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.”
Holland added that “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.”
Of course, all this data is preliminary. But you can also see some of their tracking data (though not in real time). Go to www.pacioos.org/projects/
Photo: Terry Goss/Wikimedia Commons