“After Decades Away, River Otters Make a Triumphant Return to the Bay Area” reported Bay Nature Magazine in 2016. Writer Kat McGown reported: “the fact that otters are back in the Bay Area of their own accord without any reintroduction program to help them looks like a reason to declare victory. It seems to be proof that cleaning up watersheds makes a difference, that restoration works, that species will bounce back if we only push hard enough.” She quoted Megan Isadore of the River Otter Ecology Project on how this mini-miracle occurred: “their recovery in the Bay Area is, I believe, the result of conservation and restoration activities: the Clean Water Act, the Clean Air Act, all these things we did that had a positive effect.”
In November, otters decided to explore the floating homes community. Laura Guilfoyle of East Pier reports, “I spotted a couple of playful guests on my finger pier; they gave me the privilege of watching them frolic for a few minutes before sliding back into the water.” Jay McGill of Issaquah Dock spotted what looked like a mother and pup about to embark on a swimming lesson (at least, that’s what I hope they were doing!). And Samantha Gordon videotaped two playful otters on her Gate 6 ½ float.
River otters, like their seagoing cousins, have no blubber and rely on a dense, luxurious coat of fur to stay warm. Until 1961, California river otters were trapped for that fur. In Humboldt and Mendocino counties up north and in the Delta, river otter populations managed to hang on. But from San Francisco Bay southwards, they vanished—that is, until their relatively recent triumphant return.
There are a number of differences between river otters and sea otters. Sea otters almost never come on land, but they do venture into the bay and may be spotted from time to time. They’re larger than river otters, with females weighing up to 60 pounds and males up to 90.
According to the Ocean Conservancy, river otters are found in both saltwater and freshwater, swimming with their bellies down, keeping the majority of their bodies submerged below the water. In contrast, sea otters like to swim and even float on their backs, especially while they’re eating. They’ve been known to hold hands (forepaws) with each other while sleeping so they don’t drift apart.
Sea otters use their two webbed hind feet and tail to propel them through the water, but river otters have four webbed feet that enable them to swim efficiently. In fact, a river otter’s tail is highly muscular, accounting for up to 40 percent of its total body length. With the tail’s strong, undulating movement, a river otter propels itself through the water as fast as 8 miles (13 kilometers) per hour. However, river otters can dive to only around 60 feet, while sea otters can dive several hundred feet to forage for food.
Several years ago, on Christmas Eve, my wife Jane and I had a visit from three wise otters. They explored a dilapidated old sailboat tied up next to us, as if checking out a nesting spot, but then they moved on. Unfortunately, I was unable to get any photos; luckily, others have been able to capture these unique and playful creatures for your enjoyment.