Quick answer
Otters are semi-aquatic carnivorous mammals in the weasel family, found in rivers, lakes, and coasts across the Americas, Europe, Asia, and Africa. There are 13 species, from the small river otters to the sea otter, all with dense waterproof fur, webbed feet, and streamlined bodies built for swimming. They feed mainly on fish, crustaceans, and other aquatic prey, and are known for their playful behavior and use of tools. Most otters live around 10 to 15 years in the wild.
Key takeaway
Otters are semi-aquatic carnivorous mammals in the weasel family, found in rivers, lakes, and coasts across the Americas, Europe, Asia, and Africa. There are 13 species, from the small river otters to the sea otter, all with dense waterproof fur, webbed feet, and streamlined bodies built for swimming. They feed mainly on fish, crustaceans, and other aquatic prey, and are known for their playful behavior and use of tools. Most otters live around 10 to 15 years in the wild.
Overview
Otters are semi-aquatic carnivorous mammals in the weasel family, found in rivers, lakes, and coasts across the Americas, Europe, Asia, and Africa. There are 13 species, from the small river otters to the sea otter, all with dense waterproof fur, webbed feet, and streamlined bodies built for swimming. They feed mainly on fish, crustaceans, and other aquatic prey, and are known for their playful behavior and use of tools. Most otters live around 10 to 15 years in the wild.
Biology
Otter (Lutrinae) is classified as Mammal with conservation status Least Concern. Typical weight 1–45 kg depending on species; lifespan around 10–15 years in the wild.
Ecology
Diet: Carnivore (fish, crustaceans, invertebrates). Habitat: Rivers, lakes, wetlands, and coasts. Movement and social systems reflect those pressures.
People and this species
Learn before you travel or keep related pets. Wild individuals are not toys; captive care needs species-specific husbandry.
Further reading
See the full Otter profile for FAQs, taxonomy, and related guides on this site.
Behavior and play
Otters are intelligent, social, and famously playful, often seen sliding down muddy or snowy banks and wrestling with one another. This play helps young otters develop hunting and social skills. They are superb swimmers, propelling themselves with powerful tails and webbed feet, and can close their nostrils and ears underwater. Sea otters are known for using rocks as tools to crack open shellfish.
Diet and hunting
Otters are carnivores that hunt in water, feeding mainly on fish, crayfish, crabs, frogs, and other aquatic animals. They have sensitive whiskers that detect the movements of prey in murky water. With a high metabolism and no thick blubber layer, river otters must eat frequently to stay warm, while sea otters consume up to a quarter of their body weight each day. Many otters bring prey to the surface or land to eat.
Habitat and range
Otters live on every continent except Australia and Antarctica, occupying rivers, lakes, wetlands, and coastal waters across the Americas, Europe, Asia, and Africa. They depend on clean water with abundant prey and good bankside cover for resting and denning. Sea otters inhabit kelp forests of the North Pacific, while river otters range widely through freshwater systems. Their dense fur, the thickest of any animal, keeps them warm rather than a layer of body fat.
Conservation
Otter species vary in status, from Least Concern to Endangered, with several threatened by water pollution, habitat loss, and historic hunting for their prized fur. Sea otters were hunted nearly to extinction and remain Endangered, though protection has helped some populations recover. As top predators, otters are sensitive indicators of the health of freshwater and coastal ecosystems. Clean water and protected habitat are central to their survival.
Research notes
Figures for otters (Lutrinae) come from field studies, museum records, and conservation assessments that do not always agree on exact averages. Prefer ranges over single-point claims, and check whether a source describes wild, captive, or mixed populations.
Practical takeaways
If you encounter otters in the wild, prioritise distance and local guidance. If you care for related domestic or captive animals, match diet and housing to species needs rather than generic pet advice. Share accurate status information (Least Concern) when discussing conservation.
Sources
FAQs
Otter: Key Facts & Natural History?
Otters are semi-aquatic carnivorous mammals in the weasel family, found in rivers, lakes, and coasts across the Americas, Europe, Asia, and Africa. There are 13 species, from the small river otters to the sea otter, all with dense waterproof fur, webbed feet, and streamlined bodies built for swimming. They feed mainly on fish, crustaceans, and other aquatic prey, and are known for their playful behavior and use of tools. Most otters live around 10 to 15 years in the wild.
What is the scientific name of the otter?
Lutrinae
What do otters eat?
Carnivore (fish, crustaceans, invertebrates)
Where do otters live?
Rivers, lakes, wetlands, and coasts
Are otters endangered?
Listed here as Least Concern. Check IUCN and national lists for the latest assessment.