Researchers studying proposal to restore sea otter populations along Northern CA coast

SAN FRANCISCO (KGO) -- They bask in the sunny waters from Santa Barbara to the San Mateo coast. But now, researchers are closely studying a proposal to restore sea otter populations to their historic northern California habitats from the Bay Area to north to the Oregon border.

The Center for Biological Diversity filed the petitioned with the U.S. Fish and Wildlife service, pointing to concerns about the otter's habitat and long term survival.

"They're within a smallish geographic area. And one big oil spill could take out a huge percentage of that population. One big catastrophe," says staff attorney Emily Jeffers.

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And experts say the otters already face pressure ranging from natural predators to disease, often linked to human activity. Dr. Jeff Boehm is with The Marine Mammal Center, which treats distressed animals, recovered along the coast.

"Were seeing parasitic diseases, we're seeing a toxic algae, contribution to disease. And really, all of those in one way or another, kind of have our fingerprints on them," says Dr. Boehm.

He believes understanding threats to the sea otter populations could be key to any successful reintroduction. Along with helping restore their historic numbers, which were decimated, in part by fur hunters in earlier centuries.

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"And so we're really at the Marin Mammal Center about figuring out what is ailing these animals, what we can learn about that and how we can bring that to the table as we're considering how to care for these animals in any reintroduction future," explains Dr. Boehm.

And some supporters of the plan believe a successful reintroduction could benefit more than the sea otters themselves. Their populations have historically played a key role in supporting the local marine ecosystem. A system that many believe is now dangerously out of balance.

A colorful example are the kelp forests, which provide a key habitat for marine life as well as sequestering carbon. Over the last decade the forests have fallen victim to kind of environmental chain reaction, when a diseases began impacting local marine predators like Sea Stars. The result was an explosion of hungry Purple Urchins which feed on the kelp. Dr. Rebecca Johnson, Ph.D., is with the California Academy of Sciences has tracked the threat, and is intrigued by the potential of reintroducing otters, which also prey on the destructive urchins.

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"So this would also be a benefit because otters also eat Urchins, which are the things that are eating the kelp, right? So otters like those big starfish are voracious predators, and they eat many different invertebrates, including some of the invertebrates that eat kelp," she says

She notes that reintroductions can be tricky. With challenges like keeping the new animals in place and safe from harm while they establish themselves. But if the otters can be introduced successfully, experts believe the net benefit could stretch up and down the coast.

I think a future where we have healthy sea otters up and down the West Coast would be a healthy future for the ecosystem would be a healthy future for the economy, for tourism, and others who make their living on the water," echoes Dr. Boehm.

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