Orcas (Killer Whales) in Prince William Sound Alaska.

By KYLE HOPKINS – McClatchy Newspapers
An already-fragile population of killer whales that hunts Prince William Sound never recovered from the Exxon Valdez oil spill and is doomed to die off, biologists said last week. … One of the most striking surprises to emerge from the annual Alaska Forum on the Environment was the tale of the so-called “AT1” population of killer whales. Twenty years ago, the population numbered 22 whales. Today, only seven remain. … Then the tanker Exxon Valdez ran aground on Bligh Reef in Prince William Sound, and the estimated 11 million gallons it spilled killed thousands of birds and other wildlife. The whales were known to be in the area. A Los Angeles Times photo shows four AT1 whales swimming near the leaking tanker. Over the next year, more than a third of the whales died, and the population continued to fall. The group is more than a pod. It’s the remains of a larger genetic population bound by family ties and social bonds, with its own distinct “language” of calls, said Eva Saulitis, a marine biologist who works with Matkin at the nonprofit North Gulf Oceanic Society. The depleted population won’t mate with other groups, Saulitis said. The remaining whales may be too closely related to have calves, and the two remaining females are getting to old to reproduce. She estimates this group of whales will be extinct within 25 years.

Killer whales dwindling since Exxon Valdez spill, scientists say