The Sea Otter’s Guide to Skincare

What’s the longest amount of time you’ve ever spent in front of the mirror, grooming?

It’s probably not as long as a sea otter. Sea otters can spend between 11 and 48 percent of their time grooming or, as marine mammal curator at the Vancouver Aquarium Nadine Trottier says, around five hours a day.

What compels this behaviour? It isn't vanity; it's survival.

Sea otters live along the Pacific coast of North America with healthy populations in Alaska. Unlike other cold-water animals, they don’t have thick layers of blubber to keep them warm in frigid waters.

Instead, they rely on their thick fur. In fact, sea otters have the densest fur in the animal kingdom, with 120,000 to 140,000 hairs per cubic centimetre.

“Although otters might look wet, their skin is actually dry because of how thick that fur is,” says Trottier.

If water gets through this thick fur coat to their skin, otters can quickly get hypothermia.

So, how does an otter keep their skin dry?

Step 1: Clean out the grease

The individual hairs of otter fur have microscopic edges that interlock with each other to form a barrier between the water and their skin.

However, the hairs have to be clean in order to perform this crucial function. Otters eat marine invertebrates like urchins, crabs, or mussels. Grease from their prey gets in their fur, especially on their chests when they’re lying backwards and using their torso as a dinner plate.

“That’s why they have to groom for such a long period of their life, just to make sure all that oil stays out of their fur so they can stay nice and warm,” says Trottier. They use their coarse tongues to lick their fur, or their paws to clean areas like their cheeks and backs.

Otters don’t have any fur on the skin of their noses or the pads of their paws. To keep these spots warm, sometimes otters will hold their paws over their noses.

Step 2: Reach every inch

Otters need to keep every last inch of their fur groomed, but some places can be hard to reach. “Sea otters kind of have T. rex arms—they’re kind of short and stubby,” says Juliana Kirkelie-Kim, a curator at the Vancouver Aquarium.

Luckily for sea otters, their skin is quite loose, so they can pull their pelts around themselves to clean difficult to reach places. They also have very flexible backs to help them reach tough spots.

“Sometimes they’ll do kind of a summersault to get to their butt area,” says Trottier. “It’s definitely a full-time job to get to every square inch of their body. “

Step 3: Time for a blow dry

As they’re cleaning their fur, sea otters will also blow air into their pelts. “It’s adding an insulative layer between their skin and the water,” explains Kirkelie-Kim. Thick pelts with air trapped inside can act like a down jacket.

Bonus: Clean the baby

Sea otter pups are born with an even thicker coat than the adults. So thick, in fact, that it keeps baby otters buoyant while the mother can go forage for food.

They’re also quite helpless in the first few months of life, so the mother spends lots of time carefully preening her pup.

Story by Marina Wang

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