HILO, Hawai'i — A California researcher is offering a cash reward to anyone who finds a satellite transmitter that was shed by a great white shark cruising the waters near the windward coast of North Kohala late Sunday night.

The 13-foot male shark traveled to Hawai'i from the Baja Peninsula, and the transmitter tag could provide Michael Domeier of the Pfleger Institute of Environmental Research in Oceanside, Calif., with valuable data on its 2,500-mile journey.

Great whites are not commonly seen in Hawai'i's coastal waters, where tiger sharks are the most feared predator.

The great white that made its way to the Big Island is one of a dozen that were tagged in December at Guadalupe Island off Baja, about 220 miles south of San Diego. The tagging was part of a research project that began in 1999 and is now one of the largest studies of great whites, Domeier said.

Typically, the sharks linger at Guadalupe Island until about February, dining on seals and sea lions. Then they often take off for the open ocean between the West Coast and Hawai'i, where some linger in the deep water.

The shark that passed near the north coast of the Big Island this week is the second tagged shark in the study to continue on to the Hawaiian Island chain, and no one knows what they might be seeking here, Domeier said.

"That is something I would love to better understand, but I just don't have a clue," he said. "They're leaving a place that has got a lot of food for them. ... What they're doing in this warm tropical water, we just don't know."

One possibility is reproduction. Domeier said sharks tagged farther north along the California coast followed a similar migration route, and "they seem to mix in these offshore and Hawaiian waters," he said. The two distinct West Coast great white populations may meet far out in the Pacific to crossbreed.

Great white sharks are protected species, "so it's important to know where they live so they can be better protected," he said.

The low-power transmitter is designed to detach from the shark after a time and float to the surface, where it uploads its stored data to a satellite. The tag's antennae must be pointing straight up to function, he said. It won't work if it is on its side and the signal is blocked.

Domeier said the tag washed up on a remote coastal area and stopped transmitting Monday. He believes it may be as far south as the bay at Waipi'o Valley or as far north as Paoakalani Island.

He is offering a $500 reward for the tag, which contains stored data on the shark's route across the Pacific, the depths at which it swam, and the water temperatures it experienced.

Domeier can be contacted at (760) 721-1440.

Reach Kevin Dayton at kdayton@honoluluadvertiser.com.