02/10/2011 12:12 pm ET | Updated May 25, 2011

Alaska Killer Whales Ambushing Gray Whales in Aleutians

It was early May, a time when the epic gray whale migration to the Arctic had reached the Unimak Pass entrance to the Bering Sea. A group of killer whales swam excitedly back and forth in a patch of ocean off Ikatan Peninsula in the Aleutian Islands, about 650 miles southwest of Anchorage.

There were four or five of them -- all members of the secretive type that hunts only marine mammals -- and they appeared highly agitated. Soon one of the 10-ton, black-and-white predators breached from the sea near a boat with human observers, riding the swell about two miles off the wild, uninhabited coast. What was going on?

The answer -- and the kill -- came fast.

An adult killer whale suddenly surfaced with its jaws clamped tight on the snout of a gray whale calf, an animal nearly as large as itself.

"The calf wrenched itself free, but another killer whale immediately grasped it again in the same manner," the scientists reported in a study published last week in the journal Marine Ecology Progress Series. "The (two) killer whales held the calf with its blowhole inverted for several minutes until it released a mass of bubbles, stopped moving, and slowly submerged, apparently dead."

A ground-breaking, four-year research project has found killer whales using sophisticated and cooperative techniques to intercept, isolate and then kill young gray whales part-way through their annual 5,000-mile trip to summer feeding grounds in the Bering and Chukchi seas.

The team of scientists from Alaska, Washington and British Columbia also watched killer whales actually transporting their dead prey for miles along the shore -- apparently with the goal of storing tons of blubber and muscle in shallow water so they could return later and continue to feast. The predators gathered at dozens of carcass sites, revealed at the surface by oil slicks and a ripe smell. ...

Read the complete story only at Alaska Dispatch.