Floating Through LifeBy Kathy Kranking; Photos by Tom and Pat Leeson
Sea otters spend almost their entire lives in the ocean. They eat there. They sleep there. They even have their babies there.
And that suits them just fine, because sea otters have all they need to survive in a watery world. Sea otters belong to the weasel family. They live along the coasts of the northern Pacific Ocean. In this story, we show the two kinds of sea otters that live in the United States: the California, or southern, sea otter and the northern sea otter (which is a little bigger). Both are right at home in the water!
Sea otters couldn’t survive in the cold ocean at all if it weren’t for their fur. All other ocean mammals, such as whales and dolphins, have a thick layer of fat under their skin to keep them warm. But sea otters rely only on their extremely dense fur. They have up to a million hairs per square inch! (You have only about 100,000 hairs on your whole head.) Thick fur does more than keep sea otters warm. It also makes them waterproof! The fur traps a layer of air against their skin, so the cold water never touches it.
Sea otters are built for ocean life in other ways, too. For example, they have long, webbed hind feet that they use as flippers to help them swim. And when they are underwater, their nostrils and ears can close to keep water out.
Built-in nose and ear plugs come in handy when sea otters dive for food. And they do that often, because they eat a lot! A sea otter gobbles up about a quarter of its weight in food each day. That’s like a 60-pound kid eating about 60 quarter-pound burgers every day! All that food is fuel for the otters’ bodies to burn, which helps keep them warm. Some of a sea otter’s favorite foods include crabs, mussels, sea urchins, abalone (ab-uh-LOH-nee), octopuses, and—for some northern sea otters—fish.
Many animals that sea otters eat are protected by hard shells. An otter can bite through some. But to open others, it needs a little help. So it does something that few animals in the world do: It uses a tool. First the otter sets a rock on its chest. Next it smashes the food against the rock. Whack! Whack! Sometimes it puts the food on its chest and smashes the rock against it. But either way, when the shell breaks, the otter gobbles up its meal. And it does all this while floating on its back!
To stay waterproof, a sea otter needs to keep its fur really clean. Dirty, matted fur won’t keep out the cold water. So a sea otter spends a lot of time grooming, or cleaning itself. A bathing sea otter will roll over and over in the water. As it rolls, it rubs its fur with its paws. That cleans the fur and also puffs it up with air bubbles to keep it waterproof. It’s important that every inch of the fur gets nice and clean. Luckily, sea otters have very flexible bodies. So it’s no trouble to get to those hard-to-reach places.
A sea otter mom usually has one baby, called a pup, each year. Until the baby is about two months old, the mom’s body is its crib! It rests on her chest as she floats along.
The only time the mom leaves the pup is when she has to go hunt for food. Then she wraps the pup in a kind of seaweed called kelp to keep it from drifting away while she’s gone. A sea otter pup has a built-in “life jacket”—a special coat of extra-thick fur that makes it float because there’s so much air trapped in it. So, like a cork, the baby otter just bobs on the surface while its mom is gone.
By the time the pup is around two months old, it has shed this baby fur and is learning to swim and dive in its new “grownup” coat. Then its mom will start taking the pup with her on hunting trips. She’ll teach the pup everything it needs to know. So when the time comes, the young sea otter will be ready to float through life on its own!