By Jan TenBruggencate
Advertiser Columnist

The Hawaiian green sea turtle known to humans as No. 22270 has come full circle — a 3,000-mile circle.

In the process, it has provided researchers with new information on the behavior of young sea turtles.

This honu, hatched at Sea Life Park, was raised in ponds at the Mauna Lani resort on the Big Island. It was released from a boat seven miles off shore last June 20 with a transmitter attached to its shell. The transmitter sent the turtle's location to a satellite, and young No. 22270 started out on a wide loop.

It cruised along the Big Island coast for a while, and then headed far north of the Islands. It turned west and went past Maui, O'ahu, Kaua'i and finally beyond Nihoa, cutting south just short of Necker Island in the Northwestern Hawaiian Islands. Then, south of the Islands, it turned east, and began passing south of the main islands.

All the time it was in deep ocean, far from shore and far from the seaweed beds on which green sea turtles feed when they are in shallow waters.

It swam by Kaua'i and O'ahu again, and cruised into shore off Maui in October. The young turtle crossed the 'Alenuihaha Channel to South Point, Hawai'i, late in the year, and then began heading up the Big Island coast, toward the hotel pools where it was raised.

On Feb. 20, Steve Boreri, a Mauna Lani Sea Adventures diver, took a photo of No. 22270 in waters right off the hotel. And on March 12, it crawled out onto the rocks fronting the hotel. Research-ers quickly gave it a physical exam and removed the transmitter. It was healthy, but was the same size and still weighed 30 pounds — its weight at release nine months earlier.

George Balazs, a National Marine Fisheries Service researcher, said he was surprised by how readily the turtle moved from a coastal to a pelagic lifestyle. When near shore, the animals are nearly entirely vegetarian, while at sea, they are carnivorous, feeding on jellyfish, pelagic snails and fish eggs, he said.

"Our hope from the very start was that the turtle would take up a pelagic lifestyle ... but never once did I guess that it would switch back and forth from pelagic to benthic, and travel as far as it has," Balazs said.

A second satellite-tagged turtle, this one raised at the Maui Ocean Center, was released earlier this year, and appears to be starting off on a similar journey. It is already in deep ocean 100 miles south of the Big Island, Balazs said.

Other researchers are comparing the turtles' tracks with oceanographic information such as currents, water temperature and food resources, to see if they can determine what guides the turtles along their ocean voyages.

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