The Sea Otter’s Arms, Paws, and Flippers (Explained)

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Last Updated on September 23, 2022 by Tommy

All 13 otter species of the Lutrinae subfamily have four relatively short legs. They allow otters to swim, groom, walk, and manipulate (catch and eat) their prey.

As the largest otters and members of their Mustelidae family, sea otters have short arms equipped with sensitive and agile forepaws. Their hind legs have also been advantageously modified into large flippers that assist and propel their bodies as they swim or dive. 

Join Floofmania as we describe the sea otters’ extremities in more detail. We will provide the answers to the questions you might have thought of while looking at a sea otter’s arms and feet. You’ll also know how they can benefit from having visibly different forms and adaptations in their appendages. 

What Do The Sea Otter’s Paws Look Like?

The sea otter’s paws are small, rugged, and short. The third and fourth digits in each forepaw are closely joined together. 

While each paw is covered on top with fur, it is bare on the underside (palms). Black, rough sole pads are found here instead. 

The forepaws also have retractable claws that stay retracted when the sea otter is relaxed. The claws only extend when the otter needs to grasp its prey and fill its tummy. 

How Do Sea Otters Use Their Paws?

Sea otters use their paws to groom, keep themselves safe and warm, and forage and eat their prey. 

They must rely on their sense of touch to keep their fur clean and satisfy their high metabolic demands.

While vision is also useful when hunting, it can be unreliable at night or in murky waters. So sea otters primarily use their nimble forepaws to locate, grab, and collect food. They need to do these as fast and as much as possible on every diving trip. 

Sea Otters Use Their Forepaws For Foraging And Eating

Once the sea otter successfully hunts and gathers its prey from the nearshore ocean floor, it brings its fresh catch to the water surface using its forepaws. The otter lays on its back and prepares to eat the food on its chest or belly. 

They may solely use their teeth to crunch and get to the meaty insides of their favorite invertebrates. But often, they use rocks and other shell-breaking tools to pry prey loose (abalones) and smash food items (clams, mussels, and sea urchins) with their paws.

Where Did Stone-Pounding By Sea Otters Derive From?

Interestingly, this tool-pounding behavior in many sea otters may have originated from them being frustrated! 

Scientists noticed this unique but helpful expression in non-tool-using sea otters when they pounded objects and fish that they didn’t care for on hard surfaces. They have also observed this behavior in sea otters that have been robbed of their food by another otter. 

Sea otters are relatively peace-loving. So instead of fighting the otter that stole its food, the sea otter perhaps just let out its frustration in this safe but adorable manner!

Sea Otters Use Their Forepaws For Grooming

Sea otters groom themselves after every meal by washing food debris away by rolling over a few times on the water while cleaning their coats with their forepaws . 

They thoroughly comb their fur by rubbing their body in circular motions or rapid strokes in different directions using the rough pads on the palms of their paws. 

A sea otter’s body is also very flexible, and its skeleton allows its body to roll into a ball. Because of this, the sea otter can reach and groom every inch of its body, especially the base of its tail going to its lower back.

Sea Otters Use Their Forepaws To Keep Them Warm

Sea otters live in chilly waters that can drop down to 35°F. So they can lose their body heat 27X faster by staying in the water alone – and they can choose never to come ashore.

Having the thickest fur out of all the known animals helps. But, their front paws still lose heat because the fur is totally absent on the palms. 

So by keeping their paws out of the water unless necessary, sea otters conserve body heat and keep their body warm. A researcher also noticed that sea otters groomed and licked their paws (and feet) dry before sleeping to reduce the evaporative heat loss that they can get from the cold.

Sea Otters Use Their Forepaws To Keep Them Safe

Sea otters forage multiple times a day underwater where kelp forests thrive. They often live on the water surface directly above these kelp beds to conserve energy and get more time for rest.

Sea otters like to use their paws to pull and wrap their bodies in kelp before sleeping. It prevents them from drifting far away from their spot. So they can stay safely tucked even if there’s a storm or a lurking predator. 

Are The Sea Otter’s Paws Very Sensitive?

Yes, the sea otters’ paws are extremely sensitive. 

In fact, a sea otter’s somatosensory cortex, the area of its brain that receives and interprets the tactile sensory information of its forepaws, is enlarged. These areas are even bigger compared to other terrestrial mustelids.

Due to this finding, biologists tested the touch sensitivity range in sea otters. With the help of a young, rescued female sea otter named Selka, they discovered that these mammals’ paws were comparable in sensitivity to humans’ fingertips. 

But Selka was much quicker in making decisions and completing the tests. For example, it only took her 200 milliseconds to distinguish the different textures she touched. In contrast, the humans consistently took over a second in the same experiment. 

The researchers concluded that their paws’ high sensitivity was a necessary adaptation for the sea otters that needed to rely on their paws while hunting. Making quick decisions in the wild is ultimately crucial for their survival. 

Sea Otters Can Rely On Their Sense Of Touch Even When They’re Blind

We can further understand the essence of the researchers’ statement and the importance of a sea otter’s sense of touch with the help of another male otter named Walter:

He was a blind sea otter that the Vancouver Aquarium Marine Mammal Rescue Center saved and rehabilitated in 2013. Unfortunately, the otter lost his vision and suffered multiple wounds from a gunshot blast. It is one of the dangers that humans can sadly inflict on sea otters. 

But the resilient and mighty Wally fought through his injuries and recovered. He got to live his relatively normal way of life in the marine facility by feeling his way around his surroundings. 

Despite being blind, he was even able to successfully hunt live crabs underwater with the help of his sensitive paws and even did it at an amazing speed!

Are The Sea Otter’s Front Feet Webbed?

No, the sea otter’s front paws aren’t webbed. 

The digits on its front feet are separated and, therefore, not webbed.

Like mittens, their arms are covered with fur, while rough, bare sensitive pads are on the palms of the paws.

Why Are Sea Otters’ Arms So Short?

Sea otters have short arms because they don’t use them to swim or propel themselves when swimming. 

Yet their dexterous and agile forepaws are used to catch food, eat it, groom themselves, and hold their pups even while diving or swimming. 

So sea otters can multitask and use their arms for other activities even if they’re in motion in the water! 

In another sense, their short arms are also advantageous when swimming or diving. Since they don’t use them in these instances, they fold them across their chests or press them palms-down their chests.  

These convenient positions of the sea otters’ arms help their efficiency in the water. Keeping their arms out of the way while swimming or diving prevents drag force from affecting their movement, ultimately preventing their bodies from slowing down!  

What Does The Sea Otter’s Hind Feet Look Like?

The sea otter’s hind feet are large, long, webbed, and broadly flattened, which look and act like flippers. They are also covered in relatively sparse, dense fur. 

Unlike the otter’s front paws, the hind flippers have minimal to no sole pads, and their claws do not retract as well. If the pads are present, they’re only visible at the toe tips. 

Their flippers’ fifth and outermost digits are the longest and are unique to the species. They greatly help when the sea otter is swimming on its back as these toes are the ones most deeply dipped into the water. 

Aside from swimming, the hind legs are also used in grooming sea otters’ bodies. They usually rub the flippers together or against their abdomens and sides to fluff and trap air inside their fur. 

Do Sea Otters Have Webbed Feet?

Yes, the sea otters’ hind feet are webbed to the tip of their toes. Their feet resemble the flippers of sea lions but are much bigger than on any of their cousin otters. 

The interdigital membranes or webbings connect all the digits or toes in their feet into a pair of flippers (unlike their unwebbed forepaws), thereby increasing their surface area while swimming. 

The long fifth digit on each flipper allows the otter to even widen the webbings on its feet to help them swim more efficiently. 

Why Are Sea Otters’ Flippers So Different From Its Paws?

As sea otters adapted to their environment and became almost fully aquatic as time went by, their propellers’ shape, size, and location evolved. From their forearms, their primary swimming propulsors moved and developed to be their large, flipper-like hindlegs.  

Sea otters have two different modes or positions in the water while swimming or diving:

• When they swim or dive underwater, they move their bodies in up and down wave-like motions (vertical undulations). They use their hind flippers (as well as their tails) to propel themselves underwater like dolphins and other cetaceans. 
• Sea otters habitually swim and cruise on their backs. They paddle their flippers in alternate strokes to move forward on the water surface. 

In both of these instances, the sea otters’ small forepaws do not aid in propelling their bodies. As a result, their arms remain safely folded close to their chests unless they need to use them for other activities or to multitask. 

The physical differences between a sea otter’s paws and flippers account for their particular functions in the otter’s marine life. So the sea otters never need to trade their front paws for flippers.

Can A Sea Otter Walk On Its Flippers?

Yes, a sea otter can walk on its hind flippers, although awkwardly and even clumsily. 

Sea otters are almost entirely aquatic marine mammals. Only a few choose to haul out on land to either rest, let a storm pass, or get away from a predator.

A sea otter isn’t well-adapted to walking on land, and you’ll quickly notice their awkward gait. 

If you remember from earlier, we stated that the otter’s outer, extra-long fifth digit in each of the two flippers helps them to swim well. But unfortunately, these toes make it harder for them to walk on land.

Sea otters only traded off a terrestrial adaptation for a more beneficial and efficient aquatic means of locomotion. After all, they prefer to spend most of their days at the water surface.

Why Do Sea Otters Keep Their Flippers Out Of The Water While Floating?

You can often see sea otters holding their feet (and paws) out of the water surface to conserve body heat while they float on their backs.

Like their paws, the sea otters’ hind feet lose the most heat in the body because it is only covered in sparse fur and, thereby, less insulated. 

Thankfully, a sea otter’s arteries and veins are closely packed together in its flipper-like hindlimbs. This closeness allows the arterial heat to transfer to the returning venous blood to the body rather than to the cold environment. This counter-current heat exchange system keeps the sea otter’s body warm by minimizing heat loss while keeping its flippers out of the water while floating.

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Author: Gra

Hello! My name is Graciola Galo, but my friends call me “Gra” – so can you! Aside from being a dog lover, my bachelor’s degree in biology has helped me develop a deep appreciation for animals. I look forward to learning more about all kinds of wildlife in every future article I write for Floofmania and I aspire to impart that same awe and wonder to you, too!

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