Basic Facts About North American River Otters

The North American River Otter is the only river otter found north of Mexico. Its luscious pelt, which is waterproof and allows the river otter to regulate its temperature, was also a staple of the French fur trade in the 1700-1800s, has drawn hunters for hundreds of years. The color of its fur ranges from grey and white to brown and black.


Did You Know?

River otters can stay underwater for up to eight minutes and can close their ears and nostrils to keep water out. They can also dive to a depth of 60 feet!

River otters primarily eat fish. They are also known to eat whatever is easiest to find, like crustaceans, mollusks, insects, birds, oysters, shellfish, crabs, crayfish, frogs, rodents, turtles and aquatic invertebrates.


The population is unknown because the river otter is one of the hardest mammals to census, but is estimated to be over 100,000 based on harvest reports.


River otters can be found in streams, lakes, reservoirs, wetlands and along marine coasts in all states and territories of the United States and Canada. River otters are being reintroduced in the Rocky Mountain region to counter the population decrease in the 1800s.


River otters live in all types of habitats. The only consistency with these habitats is accessible high quality water and an abundant food supply.

Did You Know?

Defenders of Wildlife is a member of the new Mexico River Otter Working Group, a broad-based coalition formed to implement a strategy to promote the restoration of the river otter to the rivers of New Mexico.

A river otter will only settle in a location with sufficient coverage, usually vegetation or physical structures, such as rock piles.

River otters are very playful animals and can very often be seen playing games. Social groups are typically made up of adult females and their pups. However, there are also groups of individual males. River otters are most active at night.


Mating season: December to April.
Gestation: 60-63 days following delayed implantation.
Litter Size: 2-3 pups.

You may also be interested in:

Where We Work
The Golden state is home to millions of wild birds, mammals, amphibians, reptiles and fish that need our help.