Sea Otter Research

Researcher observing sea otters

Southern sea otters are dying at a high rate, and SORAC scientists are trying to find out why. They study how sea otters live, the risks they face and how they become sick or injured. Although we focus on the southern sea otter, SORAC staff and volunteers collaborate with the U.S. Geological Survey and other scientists to study sea otters from Russia, to Alaska, to southern California.

We Raise and Release Stranded Pups

Since 2005, SORAC has used the Aquarium’s female exhibit otters to rear stranded pups. The females bond with the pups and provide maternal care for the months it takes the pups to grow and develop survival skills. We then track and monitor these pups in the wild, from release through adulthood, to determine whether they survive and breed. We’re trying to determine if surrogacy is a viable way to raise and release stranded sea otter pups.

We Study Stranded Sea Otters

After rescuing otters that have stranded along the shore, we perform many of the same diagnostic tests used by human doctors, and we keep extensive medical records for each animal. Doing this helps us understand what a “normal” sea otter looks like so we can determine when one in our exhibit or in the stranding program is ill and how to treat it. We also conduct various behavioral and physiological studies with the animals during their time at the Aquarium.

We Study Sea Otters in the Wild

We help conduct a variety of sea otter research projects along the California coast. We capture and tag dozens of sea otters in the wild, and then we track and monitor them—some from birth to death—in an effort to understand how they live and what’s causing their sluggish recovery. These multi year studies are performed with research colleagues at the U.S. Geological Survey, the California Department of Fish and Game, and the University of California.

For instance, we’re studying sea otter mothers to determine which feeding and survival strategies are most successful.

We Retrieve and Help Analyze Sea Otter Carcasses

More than 40 percent of southern sea otters that die succumb to some form of infectious disease—an extraordinary percentage for a wildlife population. To help determine why, we respond to calls about dead sea otters and collect these animals for post-mortem analysis by pathologists with the California Department of Fish and Game in Santa Cruz.

We take blood and other samples from each dead sea otter to use in research projects on disease, contaminants, physiology, metabolism and genetics, and we store some of these samples for future research.

We Count Sea Otters

Every spring and fall, SORAC scientists and colleagues fan out across 400 miles of California coast to count sea otters as part of the USGS annual census. These counts provide a critical measure of whether the struggling population is rebounding or declining. See USGS sea otter survey results.

We Develop New Technologies

We work with medical and engineering experts to develop ways to track and monitor sea otters that cause less stress to the animals and provide us with better information. New technologies under development include smaller implantable transmitters and time-depth recorders; new physiological sensors; improved data-retrieval systems and improved surgical techniques.

Learn more in our Research and Conservation Report
Tracking Otters
Sorac researchers How do you track an otter? Most of the otters released from the Aquarium have a radio transmitter surgically implanted in their abdomens, which our trackers can hear up to a mile away with a special receiver. Being able to track these otters helps us determine whether they’re healthy, finding adequate food and reproducing.