While eight shark attacks in Hawaii might seem unrelated with different types of sharks apparently involved this year, scientists say the most recent attacks may be part of a larger pattern.
The scientists are looking at growing evidence that the attacks may be tied to seasonal migration patterns of tiger sharks from the Northwestern Hawaiian Islands to the main Hawaiian Islands.
University of Hawaii assistant researcher Carl G. Meyer said scientists are researching the migration of adult female tiger sharks to the main Hawaiian Islands to have pups during the months of October and November.
The study involves about 10 years of information and tracking more than 100 tiger sharks with sonar and satellite monitoring devices.
The tiger sharks, scientifically known as Galeocerdo cuvier, are among the shark species known to attack people and are the most wide-ranging predator in the Northwestern Hawaiian Islands, routinely swimming hundreds of miles, according to the Hawaii Institute of Marine Biology.
Meyer, who works for the institute, said a preliminary study indicates the tiger sharks migrated in deep as well as shallow water where people were swimming and surfing.
Officials with the state Department of Land and Natural Resources said most shark attacks occurs during September, October and November.
State ocean education specialist Russell Sparks said the three recent attacks on Maui are thought to have been from tiger sharks.
On Oct. 18 an 8-foot shark attacked a stand-up paddler in waters off Kanaha Beach about 300 yards offshore at a surf break known as Boneyard. His paddleboard had a bite mark that was 9 to 10 inches wide.
On Oct. 27 a 51-year-old woman was bitten by a 10- to 12-foot shark while paddling into Makena Landing in South Maui. She suffered puncture wounds to her right inner thigh and cuts to her hand.
On Sunday, Maui diver Mark Riglos was participating in an annual spearfishing "roundup" of alien fish several hundred yards off the Waiehu Golf Course in Central Maui when a shark bit him above his right ankle at 8:09 a.m. He was accompanied to shore by a friend and kept the shark away with his spear gun, authorities said.
Also on Sunday, an 8- to 10-foot shark bit a surfer’s board near Kekaha, Kauai. A witness reported seeing stripes on the shark, so authorities think it might have been a tiger shark, said DLNR spokeswoman Deborah Ward.
The other four attacks occurred between Jan. 27 and July 30, including one confirmed tiger shark attack on a surfer near Chun’s Reef on Oahu’s North Shore on April 3.
State officials considered culling sharks following fatal shark attacks in 1991-93 but met opposition from some Native Hawaiians who regarded the shark as their aumakua, or guardians.
Scientists also were doubtful that they would capture the shark responsible for the attack because tiger sharks are far-ranging, migrating from island to island.
