For tiger sharks, there’s just no place like Maui County.

The habitat around Maui, Lanai, Molokai and Kahoolawe is ideal, with plenty of favorites on the menu like green sea turtles.

But these are also popular places for people to surf and swim, which is part of the reason researchers suspect Maui has had twice as many unprovoked shark attacks over the past 20 years as any other county in Hawaii.

 

Tiger shark bites peaked in 2012 and 2013, including two fatal attacks that spurred the state Department of Land and Natural Resources — working with the Pacific Islands Ocean Observing System, a data collection project — to commission a nearly $200,000 two-year study of shark spatial behavior on Maui.

The University of Hawaii’s Institute of Marine Biology conducted the research, which culminated this week in a report finding that the spike most likely isn’t due to changes in what humans are doing.

Carl Meyer, the study’s principle investigator, said the combination of more tiger sharks being around Maui Nui may explain the higher number of shark bites. But he also cautioned against either presuming or ruling out that the primary cause for more bites is that more people are engaging in ocean recreation activities around Maui. 

“However, despite the routine presence of large tiger sharks in waters off our beaches, the risk of being bitten remains extremely small, suggesting tiger sharks generally avoid interactions with people,” Meyer said in a DLNR release Thursday.

Carl Meyer was principle investigator for a two-year study on tiger shark behavior around Maui.

Carl Meyer was principle investigator for a two-year study on tiger shark behavior around Maui.

Courtesy: Hawaii DLNR

Shark bites around Maui reached a record high of eight in 2013. There was one bite reported in 2015.

Meyer said shark behavior didn’t change year to year, and there was no shift in human behavior to account for the drop to only one shark bite last year. 

“These spikes occur all over the world, and are most likely due to chance,” he said.

Total numbers of unprovoked shark bites recorded on each main Hawaiian island, from 1995 to 2015.

Total numbers of unprovoked shark bites recorded on each main Hawaiian island, from 1995 to 2015.

Courtesy: UH/HIMB Study

Bruce Anderson, administrator for DLNR’s Division of Aquatic Resources, said the study provides important new insights into tiger shark movement behavior around Maui, and helps answer some questions about why that island has led the state recently in shark bites. 

“We agree with the study’s recommendation that the best approach to reducing numbers of these incidents is to raise public awareness of what people can do to reduce their risk of being bitten,” he said. “This has been our focus for a long time. People who enter the ocean have to understand and appreciate that it is essentially a wilderness experience. It’s the shark’s house, not ours.”

Researchers tag a tiger shark off of Maui.

Researchers tag a tiger shark off of Maui.

Courtesy: UH/HIMB

The study made clear that shark culling is not a solution. Research from previous studies has shown that sharks are so transient that if one is killed, another will eventually take its spot.

Anderson said his division will continue to work with other agencies to expand outreach regarding hazards in the ocean, such as drownings, to include shark safety information “so people can make well-informed, fact-based decisions.”

The Pacific Islands Ocean Observing System has made the data from the tiger sharks that were tagged publicly available online, making it possible to look at how individual sharks have moved around the islands over the past couple years.

“Providing ocean users, agencies, residents and visitors with relevant ocean data is our priority,” Melissa Iwamoto, PacIOOS director, said in the release. “While the tracks do not serve as a warning or real-time monitoring system, they are a great way to raise awareness about the ocean environment and to inform long-term decision-making.”

Read the full study below.

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