By Jan TenBruggencate
Advertiser Columnist

Hawai'i's green sea turtles are seaweed-eating vegetarians when they're close to shore. But when they head out to sea, they'll eat most anything they can catch.

People who paddle canoes or surf get used to seeing turtles repeatedly in the same shoreline areas, but a turtle carrying a radio transmitter recently provided researchers with evidence that they can also spend long periods in the deep ocean.

The turtle was released June 20 after living in the lagoons at the Mauna Lani Resort on the Big Island. It had been equipped with a radio transmitter that periodically would send a UHF signal to a satellite, reporting the turtle's location.

A track of the turtle's past six months showed it took a grand tour around the Hawaiian Islands.

It headed southeast through mid-July, then abruptly turned north-northwest. The turtle, known to researchers as Honu #22270, continued on that path until the end of the first week in August, when it was a couple of hundred miles north of the Islands, then turned west for two weeks.

Then it took a curving southwesterly route that took it between Nihoa and Necker islands in the Northwestern Hawaiian Islands to a point south of Necker and roughly on the latitude of south Maui. In late September it turned east and headed home.

The turtle, still a juvenile, reached south Maui in early October, and spent a while in Maui waters before heading south. At last report, it was past 'Apua Point and nearing South Point, said George Balazs, a turtle researcher with the National Marine Fisheries Service. The transmitter should keep reporting its position for several more months.

Turtles give up their vegetarian ways when they leave shore, Balazs said.

"They'll eat animal material, as long as they can catch it, like jellies, pelagic snails and fish eggs," he said. "Turtles this size tend to thrive in pelagic zones far offshore."

The Mauna Lani Hotel has a program for raising turtles and then releasing them each July 4th. It plans to release several this year with tracking devices attached.

Sandie Patton, the hotel's vice president and director of resort administration, runs the turtle program in conjunction with researchers.

"This high-tech tracking of the honu (the Hawaiian word for turtle) is very exciting and it enhances the educational and research aspects of our program," Patton said.

"We receive an updated tracking map approximately every week and we have been sharing this information with various elementary school classrooms and turtle aficionados who are tracking the progress along with us."

Jan TenBruggencate is The Advertiser's Kauai bureau chief and its science and environment writer. Reach him at (808) 245-3074 or at jant@honoluluadvertiser.com.