2001 – The Center filed a notice of intent to sue the Naitonal Marine Fisheries Service for failing to respond to the group's 2000 petition. A few months later, the Fisheries Service issued a preliminary positive finding on the petition, planning to designate critical habitat for the northern right whale in the Bering Sea.
2004 – The Center filed a lawsuit intended to force the Fisheries Service to designate critical habitat for the whale.
2005 – The Center's lawsuit ended with a court ordering the agency to designate critical habitat by June 2006. In the same year, the Center filed a petition seeking the separate listing of the North Pacific right whale under the Endangered Species Act. Despite scientific recognition of two distinct species, the Atlantic and Pacific populations were listed together as a single entity: the northern right whale.
July 6, 2006 – The Fisheries Service designated 36,750 square miles of critical habitat for the North Pacific right whale in the Bering Sea and Gulf of Alaska.
December 20, 2006 – The Center sued the Fisheries Service to separately protect the North Pacific right whale. The agency responded by proposing to list the whale as endangered, with a final listing due in late 2007.
April 8, 2008 – The Fisheries Service issued a final rule listing the North Pacific right whale as endangered as a distinct species. The same day, the Minerals Management Service began the first steps in opening up core North Pacific right whale habitat to oil and gas leasing.
March 31, 2010 – An offshore oil and gas lease sale proposed for whale critical habitat in Alaska's Bristol Bay was cancelled, partially in response to a lawsuit by the Center and allies.
April 17, 2012 – Following a March 20 notice of intent to sue by the Center, the Fisheries Service announced that it had begun preparing a recovery plan for the highly endangered North Pacific right whale. At the same time, the agency announced it would be updating its long-outdated recovery plan for endangered blue whales, the largest animals that have ever lived on Earth.
January 23, 2013 – The Fisheries Service proposed a recovery plan for North Pacific right whales — with as few as 30 individuals left in the Bering Sea and Gulf of Alaska and only a few hundred in Russia's Okhotsk Sea.
June 7, 2013 – Following the Center 's 2012 notice of intent to sue, the Fisheries Service published a recovery plan for the North Pacific right whale, with as few as 30 individuals in the Bering Sea and Gulf of Alaska (and perhaps a few hundred in Russia's Okhotsk Sea) remaining.