Mother and pup

A beautiful animal…

Sea otters are members of the weasel family, with large eyes and thick, dark brown fur. Their rich pelt has up to a million hairs per square inch which substitutes for blubber to keep them warm in cold water.

Among the very few marine mammals known to use tools, they break open clams and abalone with stones to get at the meat inside. These intelligent animals live in shallow water and prefer kelp forests, sometimes anchoring themselves in one place by wrapping strands of kelp around their bodies while they rest.


Urchin Bed - Sea otters prey on sea urchins, keeping their populations in balance.

Sea otters are a keystone species in the kelp forest ecosystem, eating sea urchins, clams, snails, sea stars, squid, octopuses and abalone. When present in healthy numbers, they keep sea urchin populations in check. When sea otters decline, however, urchin numbers explode—as does their grazing pressure on bull kelp. The urchins chew off the attachments keeping bull kelp in place, causing them to die and float away. This decimates kelp beds and sets off a chain reaction that depletes the food supply for other marine animals and in turn causes their decline.

…nearly hunted to extinction

Ironically, the thick fur that sustained sea otters for hundreds of thousands of years nearly brought them to extinction when European trappers discovered their value in the 18th and 19th centuries. Before 1741, when Russian explorers discovered and began to hunt otters on islands off the Alaskan coast—using enslaved native peoples like the Aleuts to help with the slaughter—there were between 150,000 and 300,000 otters living between Alaska and Baja California. During peak hunt years, 500 to 600 otters were killed every week in San Francisco Bay alone. By 1911, when the International Fur Seal Treaty was signed, giving otters some protection, there were only 1,000 to 2,000 animals left alive throughout the entire range. Today, sea otters are extinct in virtually the entire coast of North America south of Alaska. Only one small population remains in the vicinity of Big Sur, California.

Saving the Alaskan Sea Otter

Steller Sea Lions - by Gerald and Buff Corsi,Declining Species and Ecosystems. There are two populations of Northern sea otters: E. lutris lutris (the Russian sea otter) and E. lutris kenyoni (the Alaskan sea otter). Recent data collected by both the Fish & Wildlife Service and the U.S. Geological Survey show that the Alaskan sea otter population in the Aleutians declined by 95% since the mid-1970s, when it numbered some 50,000 to 100,000 strong. From 1992 to 2000 it may have declined by 70%. Today, as few as 6,000 otters may remain in the entire Aleutian chain.

The decline may be due to increased predation by killer whales. Killer whales normally don't eat sea otters because they are too small. The whale's usual food source, Steller sea lions and harbor seals, have declined drastically in recent years, however, causing the whales to shift to sea otters. Steller sea lions are already listed as "endangered" species under the U.S. Endangered Species Act. The unraveling of the marine food chain, from Steller sea lions to killer whales to sea otters to urchins to the kelp beds themselves, is a grave sign of ecosystem stress beginning to take its toll.

On October 25, 2000, the Center for Biological Diversity formally petitioned the U.S. Fish & Wildlife Service to list the Western Alaska/Aleutian Islands population of the sea otter as "Endangered" under the Endangered Species Act (ESA). The petition was based on the agency's own biological data and called for immediate listing and protection to save the population from extinction.

Rather than act on our petition, however, the Fish & Wildlife Service placed the population in administrative purgatory. On November 9, 2000, it designated the sea otter in the Aleutian Islands a "Candidate" species under the Act -a designation without protective status. In the agency's own words, "Candidate Species status does not restrict any activities of any kind."

After working with the Bush Administration for years, the Center was forced to file a lawsuit in order to stop the Bush Administration's illegal actions. Mere weeks after the lawsuit was filed, the Bush Administration published a proposed rule to protect the sea otters under the Endangered Species Act, America's safety net for fish, wildlife, and plants.

However the Bush Administration never finalized the proposed rule. Meanwhile, the government's own scientists discovered that the sea otters continued to decline, and perhaps at a more rapid rate. In an article published in 2005 in the peer-reviewed journal Marine Mammal Science, biologists from the U.S. Geological Survey and the U.S. Fish and Wildlife Service noted that literally thousands of additional sea otters have been lost or killed while the Bush Administration has unjustifiably delayed protecting the animals.

After nearly five years of delay, the Center filed a lawsuit against the Bush Administration demanding immediate protection for the sea otters, because once they are gone they are gone for ever. The Center loses money every time it must file a lawsuit, but we believe that we owe it to future generations to protect imperiled animals such as the sea otter. The Endangered Species Act has a proven track record of protecting endangered species from extinction, and this lawsuit will insure that the Bush Administration's attempts to gridlock government and prevent biologists from having the tools they need to recovery the species will not succeed.


Sea otters have been called the "old men of the sea" by sailors and fishermen because of their white whiskers and expressive faces.
Otters often anchor themselves in one place by wrapping strands of kelp around their bodies while they rest.

Gill Netting Shut Down to Protect California Sea Otter

A Roller Coaster of Decline and Recovery. Having been hunted to extinction along virtually the entire coast south of Alaska, 38 southern (or "California") sea otters managed to survive in a small population near Big Sur, California. By the 1970s, the population had increased to 1,800 individuals. It then began to nosedive due to gill netting as otters got entangled in the near-shore nets and drowned. With the passage of the Marine Mammal Protection Act in 1972, and the transfer of gill nets farther offshore, the population began to recover and was at 2,377 by 1995. Plans were made to declare it "recovered" and remove it from the Endangered Species list.

Between 1996 and 1999, however, the population experienced a sudden downturn. In 1999, only 2,090 were found. A spring 2000 survey counted a total of 2,317 otters, but government biologists do not know whether the apparent upward trend will continue.

Threats to the population are not fully understood but are thought to include by-catch in commercial fisheries and oil spill pollution. In 1998, the National Marine Fisheries Service (NMFS) estimated that the set gillnet fisheries in Monterey Bay alone had killed 7, 28 and 41 sea otters in 1995, 1996 and 1997 respectively.

Protecting the Ecosystem to Protect Otters. To end by-catch kill, the Center for Biological Diversity and the Turtle Island Restoration Network filed a formal 60-day notice of intent to sue the California Department of Fish and Game for violating the ESA by allowing the killing of California sea otters in the state-managed halibut fishery in the Monterey Bay area.

In response, the state shut down the Monterey Bay set-gillnet fishery for halibut and angel shark on September 11, 2000. The order bans gillnetting in waters less than 60 fathoms from Pt. Reyes to Yankee Point, and thus effectively bans gillnet fishing in most of the Monterey Bay National Marine Sanctuary. Since the fishery also kills 120 harbor porpoises, 5,200 common murres, elephant seals, and California sea lions annually, the victory is important for the entire ecosystem. Common murres have declined from one million to about 100,000 on the Farallon Islands in the past two centuries.

In issuing the 120-day emergency closure, DFG admitted otter and murre populations could be jeopardized by the fishery. The closure also shuts down a portion of Santa Barbara County to gillnet fishing. In total, the closure will protect 150 miles of California's coast.

graphic Andrew Rodman ©2002
June 1, 2005
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