North American River Otter

North American River Otter

Scientific Name:
Lontra canadensis

Widespread in Canada, Alaska and Midwestern and Southeastern United States

Inland waterways, estuaries, and marine coves.

Average Size:
Body Length: 26-42 inches
Body-Tail Length: 38-60 inches
Weight: 6-31 pounds

About 20 years in captivity

Population Status:

Wild: Fish, frogs, crayfish, crabs, other aquatic invertebrates.  Birds, rodents and rabbits are also occasionally taken.
Zoo: Meat, bones, fish

Gestation: Pregnancy can last up to 380 days due to delayed embryo implantation.  Actual embryo development is approximately 60 days.
Litter size:1-5, more usually 2 or 3

River Otter are a dark glossy brown on the back, fading to a silvery-gray on the chest and belly.  The have long whiskers and small ears.  The tail is thick and muscular.

Bobcats, coyotes, raptors, alligators and other large predators.  Also humans.

North American River Otter Map

About the Animal: River otters are members of the weasel family, like skunks and ferrets.  Like most species belong to the mustelid family, most of their day is spent playing and sleeping.  They are excellent swimmer, capable of holding their breath for 8 minutes at a time.  They propel themselves through the water using the hind feet and tail. In this manner, River Otters can propel themselves through the water at speeds of 7 miles per hour.

Although they bear the name ‘River Otter’, these otters will readily take to marine habitats as well.  Sometimes they are mistaken for Sea Otters.  River Otters do not eat while floating on their backs – Sea Otters do.

River Otters are considered environmental indicators, and are only found where there is clean water. Serious environmental pollution extirpated the River Otter from much of its traditional range.  Water clean-up initiatives and wild relocation programs are helping River Otters make a comeback in many areas.

Mating and Reproduction: River Otters mate in the winter or spring, but the pups are not born until the following year because of delayed implantation – actual development takes about 60 days.  Male otters do not help raise the young.

Amazing Information: Otters inhabit dens near the water – usually they ‘steal’ these dens from muskrats or beavers