Otter Facts

An otter is a small, slender semiaquatic mammal that can be found in marine, freshwater, and estuarine environments. They have an average lifespan of 10-15 years. The 13 species of otters are divided into two groups, Lutrinae and Lutrinae, with the former being Asian and the latter being African and European. Some are endangered due to the number of threats they receive. These include pollution, habitat loss, and hunting.

Quick Navigation

Otter Facts for Kids

  • Otters live for 10 – 15 years
  • They eat fish, crustaceans, and other critters
  • Their predators are orcas, great white sharks, and other large animals
  • Their fur hair is kept waterproof with grooming.
  • Freshwater otter pups are born completely blind, toothless, and immobile.
  • They eat 25 percent of their weight in food per day

Where do otters live?

They are semiaquatic freshwater or marine mammals that live in and around rivers, lakes, and along ocean coasts. Freshwater species tend to live near lakes, bogs, swamps, streams, and rivers, while saltwater-dwelling otters may live in part or entirely in the ocean, albeit close to coasts.

These animals are found worldwide. In Africa, there are at least three species that inhabit large areas of sub-Saharan Africa and one species in North Africa. In North America, there are two species in the United States and Canada, with one species found throughout Central America.

There are four species that inhabit inland and coastal areas of South America, including large parts of the Amazon and along the continent’s western coast. In Europe, there is a species that inhabits the entire continent, including Turkey, the British Isles, and Scandinavia.

In Asia, there are several species, including animals found in the Caucasus region, Central Asia, China, India, the Korean Peninsula, much of Russia, and Southeast Asia — including all of mainland Southeast Asia, as well as Java, Sumatra, Borneo, and parts of the Philippines.

What do otters eat?

They eat a variety of foods depending on their species. Freshwater species tend to eat fish, crabs, crayfish, amphibians, insects, mollusks, small rodents, and snakes, but also birds, reptiles, eggs, worms, turtles, and even caimans.

Saltwater species may eat sea urchins, snails, abalone, clams, mussels, fish, crabs, and other crustaceans.

How fast can otters swim?

Most have webbed feet and powerful tails that allow them to swim at significant speeds. The Giant Otter species have been recorded swimming at speeds of up to 9 miles per hour (14.4 kilometers per hour).

The Sea Otter can reach speeds of up to 5.6 miles per hour (9 kilometers per hour) below water, with a water surface speed of 0.9 miles per hour (1.5 kilometers an hour).

River Otters of North America can swim at speeds of 6.8 miles per hour (11 kilometers per hour).

What is a group of otters called?

A group of otters can be referred to by many names. Among these are a raft (when the animals are in a group in the water), a lodge, a bevy, a romp, or a family.

Depending on the species, groups of these mammals can range from around six to twenty individual members. The largest freshwater instances of otter families can include up to groups of twenty — and this is common in species located in Asia, Africa, and South America.

Groups may include a mother and its young, called pups — or a mother and father and pups, in some species. Many species may have periods where individuals lead solitary and territorial lives.

The Sea Otter is unusual in that it can congregate in groups as large as 2,000 individuals, collectively known as a raft. This number, however, is a rarity, with rafts usually gaining numbers of around 10 to one hundred individuals.

How do otters protect themselves?

These animals can have predators that range from polar, black, and grizzly bears to mountain lions, coyotes, foxes, wolves, bobcats, crocodiles, caimans, eagles, sea lions, sharks, orcas, and pythons.

In order to protect themselves, they will either take to the water, where land-based predators can not reach them — or hide in burrows or dens alongside the shore (this is especially the case with freshwater-based otters). Some species will also form family groups to protect their young.

The Sea Otter can be hunted by orcas and sea lions. In order to protect itself, it can swim away, take to land, or retreat into its home territory, the underwater kelp forest.

Why are otters endangered?

These aquatic animals are endangered for a number of reasons, among them that they are hunted and trapped for their fur (or as bushmeat), their habitat has experienced reduction through wetland removal or deforestation, and that they may be killed by those in fishing or farming activities.

Fur trading has historically been a reason for dwindling their numbers. The Sea Otter was once believed to exist in populations in the hundreds of thousands (from one hundred thousand to three hundred fifty thousand), but the fur trade did immense damage to their numbers.

From the mid-18th century to the beginning of the 20th century, they was hunted to the point where almost one or two thousand animals were estimated to exist. This has since changed with conservation efforts, but the species still remain endangered.

Otters in other environments — especially in Asia, Africa, South America, and Europe — are experiencing habitat loss and threats from hunting and pollution. These factors have caused the animals’ populations to reduce to Near Threatened, Vulnerable, Endangered, and Critically Endangered status. 

Some species — like the North American River Otter — have been listed previously as endangered but have since returned to greater numbers. This is because of conservation efforts and the reintroduction of the species to traditional habits.

What is an otter’s home called?

Their home is called a holt. This area, especially present in freshwater species, is a place where pups are kept for safety. The holt may be a hole dug near a body of water by the otter itself or created out of a den, nest, or lodge of another animal (like a beaver).

Alternately, some species may build nests out of plant materials, the Giant Otter being exemplary. The Sea Otter does not live in a holt but does dwell offshore in underwater kelp forests and can remain in the ocean for long periods of time.

How do otters stay warm?

These creatures can live in cooler environments, and as such, can consume some fifteen to twenty-five percent of their body weight to stay warm. This high caloric consumption makes up for their high body-temperature-maintaining metabolism.

The Sea Otter has a two-layer coat that consists of a waterproof exterior layer and a high-density fur layer underneath the fur to keep them warm in cold water. The lower layer consists of almost a million hairs per square inch.

Types of Otters

Eurasian otter (Lutra lutra)

The Eurasian otter is characterized by webbed feet and claws and very short limbs. Its snout has some sensitive whiskers for prey detection. It also has two fur layers. Its average body size ranges between 1-1.3 meters. The average weight of an adult ranges between 7-9 kg.

They have a gestation period of 9 weeks and can give birth to 2-3 pups. Its primary source of food involves fish, other small mammals, frogs, and birds.

They can be found in rivers, lakes, and rocky coasts. The Eurasian otter is widely distributed in most parts of Europe and Asia. It’s also sparsely found in some parts of North Africa, such as Tunisia, Morocco, and Algeria. Recently, there have been a few noticeable cases in the Middle East in nations like Israel, Iran, Jordan, and Iraq.

With the destruction of its habitat to pave the way for other amenities, there have been many fears that this otter could soon be an extinct species.

Hairy nosed otter (Lutra sumatrana)

Its name is derived from its appearance. Its nose is very hairy and has a black part. They are characterized by a long and slender body. Its average body size ranges between 1.05 to 1.34 meters. Its tail is much longer compared to others.

The average body weight varies between 5 to 8kg. It has a gestation period of 9 weeks and can give birth to 1-4 pups. The primary source of nutrition is fish, water snakes, amphibians, crabs, birds, and mollusks. Their history dates back to the 20th century where they were first seen in Southeast Asia.

After some years, people believed that they became extinct, although they were noticed again in 1999. They’re distributed in many parts such as Malaysia, Vietnam, Cambodia, and Thailand.

Although much research is being conducted to find suitable ecological conditions to prevent extinction, they’re among the most vulnerable otter species.

Spotted necked otter (Hydrictus maculicollis)

This otter is characterized by some brown and white spots on its neck. It’s also slender and has strong webbed toes and powerful claws for killing prey. Its average body size ranges between 0.85 to 1.05 meters. Their average body weight varies between 4 to 7kg.

However, the males are bigger and muscular than their female counterparts. They have a gestation period of two months and can give birth to 2-3 pups.

They majorly feed during the night, although some can feed even during the day. They eat fish, crabs, insects, mollusks, among other water organisms.

They generally live an aquatic life and usually prefer rocky places with clear water, including rivers, swamps, lakes, and mountain streams. They’re widely distributed in Central Africa in both rivers and lakes.

Some of their common places include Lake Tanganyika, Lake Victoria, and River Zambezi. People living in other moist parts of Africa have also seen them.

Smooth-coated otter (Lutrogale Persipicillata)

It resembles a Eurasian otter, although it has huge webbed feet, flattened tail, and short fur. Its color variations include black and sandy brown. Its average body size is approximately 1.21 meters.

The average body weight of an adult smooth-coated otter ranges between 7 to 10kg. Their gestation period is two months, and they can give birth to 2-5 pups. Their primary source of nutrition is fish, crustaceans, and shellfish.

Their main habitats include rivers, swamps, and estuaries. They are widely distributed in Asia, including China, Indonesia, Malaysia, and some parts of India. Some parts of Iraq also have this otter.

North American river otter (Lontra canadensis)

This is a playful otter characterized by webbed feet and short legs. The webbed feet make it swim faster in water, especially while chasing prey. It also has a flattened head, narrow-body, long tail, and long whiskers for prey detection.

The average body size ranges between 0.9 to 1.2 meters. The average weight of a mature otter varies between 5 to 14 kgs. Their primary source of nutrition is fish, turtles, water snakes, frogs, birds, crabs, rabbits, and some aquatic plants.

They can perfectly live a semi-aquatic life, unlike other species. Their best habitats include rivers, lakes, marshy areas, estuaries, and ponds.

They’re mostly found in the United States and Canada. They usually communicate through screams, whistles, and growls.

South American river otter (Lontra provocax)

It’s also called the huillin. These are among the smallest otter species. Its characterized by a small body and relatively short tail. They also have long whiskers for prey detection, especially in a muddy area.

Their average body size ranges between 1 to 1.2 meters. On the other hand, the average weight of a South American river otter is approximately 9kg. They give birth to 1-6 pups. They mainly feed on crustaceans, fish, amphibians, birds, and mollusks.

They’re best suited to a number of habitats such as marine coastlines, rivers, lakes, marshy areas, and rainforests. The South American river otter is mainly found in Western Argentina, Chile, and Patagonia humid forests.

Neotropical river otter (Lontra longicaudis)

This otter has a long and flat skull, long and wide tail, round ears, and small eyes. The average body size of a Neotropical river otter ranges between 0.36 to 0.66 meters. On the other hand, the average weight of a mature otter varies between 5 to 15kg.

They mainly breed during spring. Their gestation period is 56 days, and they can give birth to 1-5 pups. The young pups are usually born blind and start seeing after approximately 44 days.

They mainly feed on fish, mollusks, birds, insects, reptiles, crustaceans, and other small mammals. Their main habitats include lakes, water streams, and other watery environments covered with vegetation.

The Neotropical river otter can be found in Northwestern Mexico and other South American regions such as Northern Argentina, Uruguay, and Paraguay.

Marine otter (Lontra felina)

It’s also called a sea cat. The marine otter is among the smallest otters. It’s characterized by a dark coat, complete webbed feet, short tail, and stiff whiskers around the upper lip. The average body size of an adult is approximately 0.9 meters.

Its average weight ranges between 3 to 5kg. The marine otter is a monogamous otter species with a gestation period ranging from 60-65 days and can give birth to 2-4 pups. They mainly feed on mollusks, crustaceans, birds, fish, fruits, and other small water mammals.

They’re generally well adapted to marine areas with heavy sea movements, strong winds, and rocks where there’s plenty of fish, crustaceans, and mollusks.

They are widely distributed along the pacific coast in areas like Northern Peru, Chile’s coastline, and some parts of Argentina.

Giant otter (Pteronura brasiliensis)

It’s characterized by a huge and masculine body and is among the largest otters ever. It’s endothermic and also has bilateral symmetry. Its average body size is approximately 2 meters.

On the other hand, its average weight is about 24kg. They mostly breed in early summer or late spring. Its gestation period is 68 days, and it can give birth to between 1-5 pups.

This species knows how to hunt during broad daylight properly. It majorly feeds on fish, crustaceans, small caiman, and water snakes. They prefer living in lakes, freshwater rivers, and creeks.

They can be found in South America in areas such as the Lake Plata river systems, Amazon, Orinoco. There are a few cases in Colombia, Northern Argentina, and Venezuela.

Asian small-clawed otter (Amblonyx cinereus)

This is another small otter species characterized by greyish brown or dark fur and some cream coloration on the neck and face. It has partially webbed feet and short claws compared to other species.

Their average body size is 0.4 to 0.6 meters. On the other hand, the average weight of an adult Asian small-clawed otter ranges between 2.7 to 5.4kg. They live a monogamous life and have an average gestation period of 60days and can give birth to 1-2 pups.

They feed on fish, crabs, amphibians, and mollusks. Their best habitats include rivers, coastal areas, and shallow streams. They are mainly found in coastlines of Southern India, Southern China, and the Malay Peninsula.

African clawless otter (Aonyx capensis)

These are among the world’s largest otters with a huge head, long tail, and large body length. Most of them have a thick, shiny coat with some white coloration on the neck, upper limbs, face, belly, and ears. Their average body length ranges between 7.6 to 8.8 meters.

The average weight of a mature adult ranges between 10.6 to 21 kg. The males are heavier and muscular than their female counterparts. They have an average gestation period of 63 days and can give birth to 1-5 pups.

The African clawless otter feeds on fish, crustaceans, birds, and other smaller mammals. They majorly like aquatic life and prefer residing near rivers and freshwater springs.

They are found in African countries such as South Africa, Senegal, and Ethiopia.

Congo clawless otter (Aonyx congicus)

It’s powerful and well-built with a huge head and body. Its feet aren’t webbed like other species and also lack claws. Their average body length ranges between 1.2 to 1.6 meters.

The average weight of an adult ranges between 15 to 25kg. It has an average gestation period of 2 months and can give birth to 1-6 pups.

Their main source of nutrition is fish, amphibians, terrestrial worms, mollusks, crustaceans, and other small mammals.

Their main habitats include ponds, swampy areas, and rainforests. They’re majorly found in the Congo basin, Western Uganda, Southeastern Nigeria, Gabon, and Equatorial Guinea.

Sea otter (Enhydra lutris)

These are also among the largest otter species characterized by brown pelage and two coat layers. They also have a circular face with round eyes. They also have long whiskers for prey detection and long legs with strong paws and webbed feet.

Their average body length ranges between 1 to 1.5 meters. The average weight of a mature adult varies between 14 to 45 kg, and the males weigh more than the female sea otters. Their average gestation period is 6months, and they can give birth to 1-2 pups.

They are usually carnivorous and prefer eating fish, sea urchins, crabs, coast mussels, octopus, and limpets.

Their preferred habitats include coastal waters and other watery environments with forests. They can be found on the pacific coast in areas like the Russian coast, Canada, Vancouver Island, and Central California coast.