University of Hawaii researchers and state officials confirmed today that it was a tiger shark that fatally attacked a surfer at Honolua Bay earlier this month.
A pair of shark researchers at the UH Hawaii Institute of Marine Biology used new DNA barcoding technology to determine the type of shark — and say it was undoubtedly a tiger shark. The measurement of bite marks on the late surfer’s board determined it was about 14.3 feet long.
On Dec. 8, a 56-year-old man later identified as Robin Warren of Napili, encountered the shark while paddling out from the old ramp at Honolua Bay at about 7:50 a.m., according to the Department of Land and Natural Resources.
He was taken to Maui Memorial Medical Center, where he underwent surgery, but eventually succumbed to his injuries.
Historically, researchers have relied on observations by the victim or bystanders, according to renowned shark expert Carl Meyer, but sharks can be difficult to identify.
In Hawaii about 40% of shark incidents, the species is not definitively identified, according to Meyer, compared to 70% globally. A scientific approach helps reduce the uncertainties.
“Prior to the development of these new techniques, uncertainly over the size and species of sharks responsible for bites to people was common,” said Meyer in a news release. “We are absolutely certain that it was a large tiger shark (in the 98th percentile for size), that bit this man.”
State education specialist Adam Wong used a swab kit developed by the researchers to gather trace samples of DNA from the bite impression left on the surfing victim’s board. State officials responding to shark encounters are now equipped with the swab kits for this purpose, and the new technique will be used going forward.
“Once we received the sample from Maui, we used these new techniques to determine the species and size of the shark involved in the recent Honolua incident,” said Derek Kraft, a UH Sea Grant Fellow, in the release. “These new techniques can be applied in future incidents to help us gain a clearer understanding of these events…which fortunately are quite rare.”
The swab kits can recover shark DNA from any item that comes in direct contact with the shark, including surfboards, wetsuits and fish. The swab samples are ideally taken within hours of an incident. In this case, they were taken after two and a half days.
Officials and researchers extended their condolences to Warren’s family and friends over the tragic incident, and hope the new technology can lead to greater insight.
“There’s a lot that we don’t understand about shark bite incidents,” said Meyer, “and so we’re trying to get as much factual information as we can in order to first of all, make sure we’re able to inform ocean users to the greatest extent possible about the risks of their activities. And hopefully, in the future, to find ways to reduce the risk.”