Otters in the SF Bay Watershed
Otters thrive in healthy habitat, which means clean water, diverse riparian (shoreline) plants and access to fish and other prey. Burrowing into the muddy banks of the shore, otters create dens called “holts” or “couches.” With an underwater entrance to keep out predators, the holt is a safe place for otters to raise as many as five pups at a time.
River otters are capable hunters who enjoy a variety of food sources. As semiaquatic carnivores, their prey largely consists of fish, but they’ll also snack on crustaceans, aquatic insects, frogs, rodents and even birds. Otters living in fresh or brackish (slightly salty) marshlands prefer to feast on abundant crayfish and crabs.
The marshlands found in the San Francisco Bay area are immensely productive and diverse ecosystems that can support a thriving otter population. Unfortunately, with the development of the Bay, these wildlife havens have all but disappeared in the last 150 years. As restoration projects slowly restore leveed salt ponds back to tidal marshes, the otters will return to contribute to a healthy, diverse ecosystem.