''There's a group of whales going extinct in Prince William Sound, and I don't think people realize that,'' said Pat Lavin, with the National Wildlife Federation, one of the groups seeking the action. Listing them as depleted would be an essential first step toward preventing further harm, he said.
The request concerns a group of killer whales known as the AT1 group, which lost 13 of 22 members over the past 13 years.
A depleted listing would require the National Marine Fisheries Service to figure out if something could be done to help the animals.
The groups filing the petition say it also would draw dramatic attention to the worldwide problem posed by the spread of industrial pollutants and pesticides banned in the United States but still produced in Asia.
''I don't necessarily think we can stop these animals from going extinct, but this will raise awareness of the sensitivity of these animals,'' said Craig Matkin, the region's leading killer whale researcher, with the North Gulf Oceanic Society of Homer. ''If there are outside influences that can be manipulated to help these animals, this is the way to do it.''
The AT1 killer whales once stalked harbor seals in the remote bays of Prince William Sound and Kenai fjords with a regularity rarely seen among the marine mammal-eating orcas known as transients.
Researchers often saw all 22 members of the group every season and recognized their eerie sirenlike calls. Several animals were so well known they had been named by Cordova mariners.