Do sea otters ever come ashore?

Sometimes, but they spend most of their lives in the ocean. Sea otters eat, sleep, mate and have their pups in the water. Occasionally, females come ashore to rest after mating, and any otter may beach itself if it's ill or injured. Remember, if you see an otter on land, leave it alone and ask other people not to disturb it.

Do sea otters groom themselves a lot?

A sea otter's fur keeps it alive in the icy water, so each sea otter spends a couple of hours a day grooming to keep its coat in good shape. You'll often see otters rolling in the water and rubbing themselves-they're cleaning their fur and rubbing insulating air into the hairs. They're extremely limber, and their skeletons are very loosely jointed, so otters can groom every inch of their bodies-even the middle of their backs.

Do sea otters live alone or in groups?

Sea otters live in loose-knit groups called rafts. Rafts typically consist of two or more resting otters. Otters in rafts often sleep side-by-side, wrapped up in strands of kelp, so that they don't drift far from each other.

Males and females usually live in separate groups. Females have small home territories; they and their pups may gather in large groups. Mature males protect large territories, encompassing the territories of several females. Males and females form breeding pairs for only a short time, usually only three to five days. After this, the male moves on to look for other receptive females and the female raises the pup on her own. On the outskirts of the range are rafts of bachelor males, too young or too old to hold their own territories.

Do sea otters mate for life?

Sea otters don't mate for life. At the time of mating, the male and female form a pair bond that lasts three to five days. Females sometimes mate with the same male in subsequent years, although not always.

What's the gestation period for sea otters?

The gestation period for a sea otter is about six months. The female otter is able to delay implantation of the fertile egg for several weeks. Some scientists suggest that this may help ensure that the pups are born when food is plentiful. The exact mechanism that controls implantation is not known.

How many pups do sea otters have?

Females usually give birth to one pup a year, although twin births occur occasionally.

Does the father help to raise the sea otter pup?

No, the father leaves the mother soon after mating, and he's not involved in any way with raising the pup.

How much do sea otters weigh when they're born?

Sea otter pups weigh three to five pounds (1.4-2.2 kg) when they're born.

Do sea otters use tools?

A sea otter may use rocks to crack open hard-shelled prey at the surface, either setting a rock on its stomach while floating on its back, or holding rocks with its forepaws to pound its prey. Otters may also use rocks to pry up abalone and sea urchins. Around the Monterey wharf, some otters use discarded glass bottles in the same way!

How deep do sea otters dive?

Southern sea otters probably have the ability to dive as deep as 300 feet (100 m), but their typical feeding dives last just a minute or two in 30 to 60 feet (9-18 m) of coastal water.

How do sea otters keep warm?

They have the world's densest fur-up to a million hairs per square inch! (You have 100,000 hairs or less on your whole head). A sea otter's normal body temperature is about 100º F (38º C), while the ocean is a chilly 35º to 60º F (2-16º C). Sea otters carefully groom their fur to trap a layer of insulating air bubbles between their warm skin and the icy water. But even that fur can't stop the loss of body heat. Otters need to keep that fur in good condition to stay alive in the cold water. That's why oil spills and even oil runoff from streets is bad for the otters-oil degrades the otters' fur and they get cold.

How many kinds of sea otters are there?

There are three subspecies: the Russian, Alaskan and California sea otters. The California subspecies is also called the southern sea otter. They're all sea otters (Enhydra lutris), but each subspecies differs slightly in size and body shape.

How much do sea otters eat?

Without blubber, sea otters lose a lot of heat to the water. To stay warm in cold water, a sea otter burns calories at nearly eight times the rate you do. An otter fuels its fast metabolism by eating up to a quarter of its weight in food a day. (A 160-pound (73 kg) person would have to eat about 40 pounds (18 kg) of food a day to match that!)

How well can sea otters see, hear, smell and touch?

Sea otters have unusual eyeballs, adapted to see both above and below the water. But they use their sense of touch at least as much as their eyes. Their long whiskers help them detect vibrations in murky waters, and they use their sensitive paws to locate and capture prey under water. They seem to have an acute sense of smell and taste, but we don't really know how well they hear. They seem to be most sensitive to high-pitched sounds.

How many southern sea otters are there now?

Today about 2,500 southern sea otters live along the central California coast.

The Southern sea otter was thought to be extinct by 1900. But in 1915, biologists discovered a group of about 50 otters that had survived in a remote Big Sur cove. To protect these last survivors, the biologists kept them a secret until 1938, when many people saw the otters as Highway 1 was built along the coast. All of today's California sea otters descend from the tiny Big Sur colony.

Sea otters have been protected by law since 1911 and are protected as a threatened species under the 1972 Endangered Species Act.Today, there are small populations of sea otters along the coasts of Russia, Alaska and central California.

What do sea otters eat?

Sea otters eat many kinds of invertebrates, including clams, snails, sea stars, sea urchins, crabs, squid, octopuses and abalone. Alaskan sea otters also eat fish, but California otters seem to prefer invertebrates.

Aquarium researchers have discovered that each otter has its favorite foods-wild otters often hunt for only two to four of the more than 40 food animals on their menu. Mothers teach their pups to forage, and pups learn to hunt the same prey as their mothers. Some scientists think this may let more otters share the same habitat, because different otter families are hunting different types of prey.

What habitats do sea otters prefer?

Sea otters find prey along rocky shores, on sandy seafloors and in coastal wetlands. In California, sea otters are closely associated with the kelp forest. Many kinds of prey live on and among the kelp, and the otters often wrap themselves in kelp strands to stay close to their favorite feeding grounds when resting.

Sea otters actually help the kelp forest to thrive by eating sea urchins. In southern California, where sea otters have not made a comeback, sea urchins can get so numerous that they nibble the kelp forest down to stubs. In northern California, sea urchins and other invertebrates, such as limpets and snails, which consume kelp, are all kept in check by the otters.

Where can I get more information about sea otters?

Our Sea Otters exhibit section and Sea Otters Research and Conservation (SORAC) section have more information on sea otters and what you can do to help them survive.