All Sea Otters live in the Pacific Ocean, but Northern Sea Otters live around Southern Alaska, British Columbia, and Washington. Southern Sea Otters have a much smaller range that is isolated to California’s central coast. Russian Sea Otters are found off the coast of Russia, all the way down to Japan. Historically, Sea Otters used to live all along the Western US coast down to Mexico, but due to overhunting and habitat loss, they no longer inhabit these areas. The State of Oregon, historic habitat for the Sea Otters, is currently planning on attempting to reintroduce Sea Otters to their coast, to help restore historic populations.
What are Sea Otters?
Sea Otters are semi aquatic mammals, and even though they spend much of their time in the ocean, they still spend some time on land to rest, warm up, and escape predators. Sea Otters are about three times the size as their freshwater cousins, sometimes weighing up to almost 100lbs! Sea Otters have some special aquatic adaptations, including webbed feet, a thick muscular tail for swimming, retractable claws, and small ears. Sea Otters are most seen floating on their backs at the surface. Their thick fur and large lung capacity allows for easy buoyancy where they can tuck all limbs in to warm up, rest, or even eat on their backs.
Sea Otters are very social, vocal, and playful animals and tend to aggregate in groups. They are diurnal creatures, meaning they are most active during dawn and dusk, and tend to forage in the morning and afternoons. Sea Otters also spend a lot of time grooming themselves and others. This helps them to keep their coats in top shape to protect them from the cold ocean water. Adult Sea Otters tend to forage alone but will rest together in groupings called rafts. These rafts of Sea Otters are usually separated by male and female, and Sea Otters will hold on to each other or rap themselves in seaweed to prevent themselves from floating away. Male Sea Otters are usually calm, but can sometimes become territorial, especially during breeding season.
Sea Otters are carnivores, meaning they only eat meat. They can forage for their food by diving up to 250ft to find crustaceans like crabs, urchins, clams, and mussels. They also will prey on slow moving fish, octopus, and other small slow moving sea creatures. Sea Otters have a unique pouch of skin that stretches across their chest and under their forearms which they can use to store foraged food. Once the Sea Otter has caught its prey, they will use their well-adapted teeth for crushing any hard-shelled prey, and they will usually eat off their belly while floating on the surface. Sea Otters will also sometimes use tools like large rocks to help crack open difficult shells.
Sea Otters only give birth to one pup each reproductive cycle and, as opposed to their freshwater cousins, Sea Otter pups are born with eyes, ears, and teeth fully developed. Once a male and female mate, males will go off on their own and the gestation period for the females will take anywhere from four months to a year! The long gestation period can be due to an evolutionary trick called “delayed implantation”, meaning that an embryo can be paused in the beginnings of development so that it can be born when environmental conditions are best. Pups are born in the water with a thick baby coat that is replaced with an adult coat once they mature. Mothers and pups will usually stay together for six to twelve months, depending on the location they live. Mother Sea Otters will teach their pups all skills on how to hunt for survival.
Sea Otters face many threats in the wild, but their biggest threat is interactions with humans. During the 1700s and 1800s Sea Otter numbers dropped close to extinction due to overhunting from the fur trade. By the early 1900s their populations were so low that they had disappeared from much of their habitat on the US West Coast. Although their populations have risen since then Humans remain the biggest threat to Sea Otters, and they are constantly affected by boat strikes, fishing net entanglement, illegal hunting, oil spills and more!
Sea Otter populations have risen since their protection as an endangered species; however, their numbers still have not returned to their pre-fur trade population. Currently due to major oil spills and habitat loss, Sea Otters are struggling to keep their populations stable especially in the Southern populations. Although their numbers are in a slight decline, they continue to expand their geographic range North and South. Because Sea Otters are a keystone species, they are incredibly important to the health of all other animals in their shared ecosystem.
How to Help
The best way to help Sea Otter populations today is to reduce your oil consumption! Oil spills are detrimental to Sea Otter populations. If you can, try carpooling, taking public transportation, riding your bike, or just walking. Of course, there are many other ways to help too! Pick up litter you find, try and use environmentally friendly cleaning supplies, avoid pesticides and chemicals in your yard which can cause harmful runoff, try to use less water, and many more! Whatever you can do to help the environment helps Sea Otter populations. There are so many organizations that are working to help save the Sea Otters, learn about and donate to organizations that are working hard to help save Sea Otter habitat!