While sightings are rare in the Hawaiian Islands, they may have been on the rise in the past decade. The National Marine Fisheries Service cites reports of orcas feeding on small whales off Wai'anae in the early 1990s. A boater reported an orca off O'ahu in 1997. Ford said that is not necessarily unusual. Killer whales are probably second only to humans as the most widespread species on the planet.
Whale researchers say there are two distinct kinds of orca, although both are in the same species.
One is a fish eater and the other a meat eater. Ford said orcas in Hawai'i are more likely to be transients, but may eat more than just mammals. The concept of orcas attacking humpbacks is intriguing, he said. Hawai'i's humpback whales migrate each year from the cold waters off Alaska to winter and calve in the warm waters of the Islands. Bane, who viewed the orca pod feeding off Kaua'i March 20 from his Holoholo Charters tour boat, said one of the first things he and a boatload of whalewatching clients saw was a group of humpbacks behaving oddly.