A team of marine researchers was treated to the unusual sight of a small pod of orcas off Kauai during the weekend.

“It’s so rare to have killer whales in Hawaii,” said Robin Baird, a research biologist with the Cascadia Research Collective based in Olympia, Wash.

The whales appeared at about 9 a.m. Sunday in the channel between Kauai and Niihau where Baird and other Cascadia scientists are conducting a three-week project for the Navy to gauge the effect of sonar training on various species of marine mammals.

The project, which began Wednesday and ends Aug. 8, involves tagging tooth-whale species, including false killer whales, short-finned pilot whales and Blainville’s beaked whales.

“We know little of the various species off Kauai,” said Baird.

The scientists will study the habitat and population, and the behavior and response to sonar during an upcoming submarine training exercise.

Baird said they have yet to tag any whales. High winds in the channel have made the project a challenge, he said.

The orcas seen Sunday appeared to be chasing a rough-toothed dolphin.

At one point, two whales circled the researchers’ boat, coming within about 10 feet.

Baird said they stayed near the whales for about an hour but could not tag them because they couldn’t find the right angle.

“We were pretty excited,” he added.

BAIRD described one as a female adult that appeared to have cookie-cutter shark bites behind her blowhole. Baird said she was traveling with three offspring: an adult male, sub-adult male and a juvenile.

This was the first time the Cascadia researchers have spotted killer whales in the ocean off the main Hawaiian Islands since May 2003, when four killer whales appeared off Kona.

Orcas are most common in coastal waters at northern latitudes such was Washington state, British Columbia and Alaska. But some travel thousands of miles throughout the tropical Pacific, said Baird.

“Killer whales are actually distributed worldwide from the tropics to high-latitude waters,” said Baird.

Their diet consists of fish, squid and marine mammals, he said.

According to a 2006 study by Baird and other researchers, an average of two killer whales is seen around the main Hawaiian Islands every year.

The study documented 21 sightings between 1994 and 2004 off Hawaii island, Kauai, Niihau and Lanai.

Others were seen at French Frigate Shoals.

Anyone in Hawaii who sees an orca is asked to email Baird at rwbaird@cascadiaresearch.org.