Sea Otters of the Salish Sea

A sea otter hanging out in bull kelp in the Salish Sea. Photo Credit: Naturalist Tiffany Waldner

Tucked in the kelp forests of the cold waters of the Salish Sea, one of the Pacific Northwest’s smallest marine mammal, the sea otter, once helped shape the entire region. Sea otters are more than adorable marine mammals known for holding paws as they float on their backs. Sea otters are a keystone species, meaning they have an important impact on their environment. 

Sea otters prey on invertebrates such as various shellfish, crabs and, critically, sea urchins. With sea urchins in particular, sea otters help prevent overgrazing of important kelp forests by keeping the urchin population in check. Through their daily feeding habits, sea otters help maintain the delicate balance of the Salish Sea ecosystem. 

Near Extinction in the Wake of the Fur Trade

Once abundant from Mexico to Alaska, sea otters thrived in the inland waters of the Salish Sea. Their global population was once estimated between 150,000 to 300,000. But in the late 1700s, the arrival of Russian, British, Spanish, and American fur traders changed everything. Sea otters quickly became one of the most sought after animals in the maritime fur trade. 

A sea otter in the Salish Sea chowing down on a clam. Photo Credit: Captain Trevor Derie

Unlike whales or seals, sea otters lack blubber to keep them warm, relying instead on their fur for insulation. Sea otters possess the densest fur of any animal on Earth, with up to one million hairs per square inch. This extreme density made their pelts incredibly valuable. Their fur was crafted into coats, hats, and capes for the wealthy. At the height of the fur trade, sea otter pelts were worth enough money to purchase a Victorian house in England.

By the early 1900s, the global population of sea otters had plummeted to fewer than 2,000 individuals, with the species locally extinct from Washington waters.

A Second Chance

The International Fur Seal Treaty of 1911 granted sea otters protection, but in Washington State, the species had already been wiped out. It wasn’t until 1969 when recovery efforts began. The Washington Department of Fish and Wildlife relocated 59 sea otters from Alaska to Washington’s waters.

A sea otter in the Salish Sea floating on his back. Photo Credit: Captain Trevor Derie

Over the following decades, the population has gradually rebounded. As of 2019, just over 2,700 sea otters call Washington waters home. Most live along the outer coast near Olympic National Park, and although they have not fully recolonized in the Salish Sea, their gradual return offers hope for continued recovery. 

A Wildlife Experience You Won’t Forget

Kelp forests are vital for the health of the Salish Sea ecosystem. They absorb carbon dioxide, buffer shorelines from storms, and offer food, shelter, and breeding grounds for dozens of fish and marine species. The return of sea otters to Washington is a hopeful sign that these underwater forests will continue to thrive.

Dexter, the sea otter, is a regular in the Salish Sea. Photo Credit: Captain Trevor Derie

Beyond their ecological importance, sea otters are an amusing species to observe. They often wrap themselves in kelp, preventing the current from carrying them away. Sea otters are curious and intelligent, and are one of the few mammals known to use tools. They use rocks to crack open shellfish, often selecting a favorite rock and storing it in loose pockets of skin beneath their armpits. 

If you ever take a whale watching tour in Anacortes with Outer Island Excursions, you may encounter a local celebrity–Dexter, one of the few sea otters who call the waters outside of Anacortes home.

The return of the sea otter is more than a wildlife success story. It’s a reminder that when given the proper protections, both animals and their ecosystems have the capacity to recover and thrive.