Restoring Sea Otters Throughout the Pacific Coast

During Sea Otter Awareness Week 2023, Defenders of Wildlife California Representative Andrew Johnson led a public conversation about Defenders’ contributions to a southern sea otter reintroduction plan that would potentially bring this species back to parts of the coast where they are no longer present.  

Reintroducing sea otters to northern California and Oregon would restore a missing link to the coastal ecology of this region. 

Hunting for the fur trade throughout the 18th and 19th centuries extirpated sea otters from most of their habitat along the Pacific Rim. By the early 1900s, only one small population remained in California. Following federal and international protections, the southern sea otter slowly recovered and expanded along the Central California coastline until the late 1990s, when range expansion ceased. 

For the last 25 years, the southern subspecies population has plateaued in Central California; unable to repopulate critical areas beyond its existing range, such as California's northern coast. This year’s Sea Otter Awareness Week theme, “Restoring Missing Links,” highlighted the gaps in the southern sea otters' historical range, the role that sea otters play in restoring the health of nearshore habitats and the efforts required of humans to rebuild the resilience of coastal ecosystems. 

Johnson presented several reasons why the southern sea otter has been unable to expand beyond its current range, including mortality from exploratory white shark bites, the effects of climate change and the ecological impacts of a massive sea star die-off.   

In less than a decade, kelp-grazing sea urchin populations —left unchecked with the absence of predatory sea stars —  decimated the West Coast kelp forests that provide homes to unique marine life, including sea otters.   

If sea otters were reintroduced to these areas, the grazers would be kept in check. Often called ecosystem engineers, sea otters encourage healthy, diverse marine systems and help restore degraded coastal habitats. 

Defenders of Wildlife and a coalition of experts are analyzing the mechanisms, logistics and socioeconomics of restoring the southern sea otter to areas of its historical range. The coalition will then submit a conceptual blueprint for reintroduction to the U.S. Fish and Wildlife Service, which has already concluded that sea otter reintroduction is feasible.  

To determine how to effectively and best reintroduce sea otters to northern California, Defenders of Wildlife and its partners will engage with communities and organizations along the coastline, including fisheries and Tribal Nations, to understand the potential impacts and cultural importance of sea otter reintroduction.