Puget Sound Killer Whales Officially Endangered

A group of killer whales that visit Washington state's Puget Sound every summer has been listed as an endangered species under the federal Endangered Species Act, one year after the move was proposed.

Currently, the population of Southern Resident killer whales, as the group is officially called, stands at about 89 whales. During the 1970s, many members of the group were captured and shipped away to become attractions in commercial aquariums.

The group has historically been small, so they've always been susceptible to things like disease and oil spills. But busy shipping traffic in the Sound's waters, exposure to toxic chemicals and limits on the availability of food like salmon have added to the whale's troubles in recent years.

Listing the group under the Endangered Species Act will give the whales an added layer of protection and require that federal agencies make sure their actions do not harm the animals and that steps be taken to benefit the whales when possible.

--Ker Than

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Credit:  NOAA