#MapMonday: Sea Otters

Happy #MapMonday everybody! I’m excited to talk with you today about a species that’s totally “otter” this world - the sea otter!

In addition to being the totally adorable, hand-holding, mischievous marine mammals that we know and love, the sea otter is also a keystone species.

Keystone species get this name because of how similar their role is in their ecosystem to that of the keystone in an arched bridge. If the keystone were removed from a bridge, the whole thing would come crumbling down.

Likewise, keystone species have a very important role in the environments in which they live because they maintain a balance in the ecosystem. This balance is something many other species in the ecosystem depend on to survive, and without it the ecosystem would change dramatically.

The Southern sea otter can be found along the coast of California, from south of San Francisco down to just north of Los Angeles.

Sea otters serve as top predators in their environment and manage the size and abundance of their favorite food, sea urchins. Sea urchins eat kelp, and if the sea otter wasn’t around to eat the sea urchins, the sea urchins would totally devour kelp forests.

This would leave many other marine species without the food and shelter that they depend on from healthy kelp forests and ultimately create what is known as an “urchin barren,” or an area overrun with sea urchins and with few resources for other species.

This makes the persistence of the sea otter throughout its range incredibly important for the entire ecosystem, not just the sea otter alone.

As sea otters rebound from near-extinction, they have brought with them healthy, diverse, and more stable coastal ecosystems.

Sea otters first received protections when the International Fur Seal Treaty of 1911 was signed, and they received even more extensive protection upon creation of the Marine Mammal Protection Act and the Endangered Species Act in the 1970s.

However, sea otters are still struggling to return to their full historic range that once extended from Mexico all the way up the Pacific coast of North America and out past the Aleutian Islands of Alaska.

Major roadblocks to their recovery include shark bites and a lack of restored, healthy ecosystems as well as threats of oil spills, plastic pollution, fishing line entanglement, toxic algal blooms, and parasitic disease.

Defenders of Wildlife is working with local communities and Sea Otter Savvy, a program educating Californians on how to behave responsibly around sea otters, to foster sea otter stewardship along the coast and educate the public on the importance of sea otters and other California wildlife.

There is also the annual sea otter census that is completed each May to understand regional and range-wide population trends for the Southern sea otter.

This map here shows the density of sea otters per 10 kilometers of coastline from the 2018 sea otter census, with dark red being the highest density and light yellow the lowest.

Defenders also has field staff on the ground working to restore the sea otter, including our California Representative, Andy Johnson. Let’s take it over to Andy to learn more!

Sea otters in California have shown remarkable resilience over the centuries since the fur trade ended, but clawing their way back from near extinction during a period of massive human population growth along the coastline has had its challenges.

Sea otters have faced conflicts with fisheries and human recreational activities; they’ve encountered constant flows of pollutants and disease; and they’ve strived to expand their range despite attacks from white sharks, entanglements in fishing gear, and disturbance from eco-tourists.

Perhaps more than ever before, sea otters need our assistance.

For the past 25 years, a strong alliance of collaborators has studied the sea otter population in California to better understand their needs and to figure out how to best protect them, but going forward, we’ll need to devise and implement new management strategies that will promote northward expansion before true recovery of the population can occur.

With our partners at federal and state agencies, universities, and NGOs, we’ll keep working until the day when sea otters are once again performing their keystone role in kelp forests and estuaries along the entire California coast. Back to you, Mae!

Thanks, Andy! Our story map on coexisting with sea otters highlights many of Defenders’ successes on the road to coexisting with sea otters, which you can check out at the link below. Defenders also continues to work collaboratively with groups to promote the California sea otter fund and sea otter awareness week to increase awareness of sea otters as they continue to reclaim their range along the California coast and beyond. You can also support the “otterly” amazing work that Andy and his team are doing out in California by donating to Defenders of Wildlife or, if you are a California resident, donating to the California Sea Otter Fund when filing your taxes. Also remember to be sea otter - savvy and view the otters from a safe distance if you’re lucky enough to see them in the wild! Thanks for watching and happy mapping!