On February 16, 2006, the National Marine Fisheries Service ruling to protect Puget Sound's Southern Resident orcas, or killer whales, under the federal Endangered Species Act went into effect. Over the past six years, the population of whales has declined nearly 20 percent, leaving only 78 individuals in the population at the end of 2001. The cause of the decline appears to be the synergistic effects of high levels of bioaccumulative toxins, a decline in their preferred salmon prey, and human disturbance from vessel traffic and noise.
As a result of the listing, in June 2006 the NMFS announced proposed critical habitat for the protection of the whales, which includes much of the Sound but excludes waters less than 20 feet deep.
Patti Goldman, the Managing Attorney in the Earthjustice Seattle office, brought this case on behalf of a group of clients, including the Center for Biological Diversity, Earth Island Institute, People for Puget Sound, and others.