North American River Otter
The High Desert Museum introduced a new North American river otter, Lontra canadensis, into the otter display last summer. Rogue, the Museum’s 4-year old otter, was anxious to meet the new addition. After a short period of adjustment, they became the best of friends. Here’s a bit more about river otters:
Range: The North American River Otter ranges throughout most of North America including parts of Canada, the Pacific Northwest, the Atlantic states, and the Gulf of Mexico.
Identification & unique characteristics: Otters have long streamlined bodies and webbed feet. Males weigh an average of 25 pounds and females weigh 18 pounds. They range in length from 26-42 inches and one-third of that length consists of the tail. Otters have a flat head with small, rounded ears and long whiskers that act as feelers. Their fur is dark brown above shading to a silvery grey on their undersides and throat. The thick coat of river otters repels water and has about 160,000 hairs per square inch. They spend most of their time in the water and can hold their breath for as long as eight minutes. Otters can swim at speeds up to seven miles per hour and dive 60 feet below the surface. They have an acute sense of smell and hearing but are near-sighted.
Behavior & life history: This intelligent and curious animal is active year round but may be more active at night during the spring, summer, and fall and more active during the day in the winter. Known for their sense of play, they have been observed sliding down riverbanks and snowy hills, rolling over and somersaulting in the water, wrestling, and chasing one another. They are more social than other closely related mammals and can be seen living together in family groups. Otters communicate with each other with scent-marking and through a variety of vocalizations such as barks, growls, chuckles, whistles, and chirps. They hunt mainly at night and feed on a wide variety of prey including mammals, waterfowl, turtles, salamanders, frogs, slow-moving fish, crayfish, and aquatic insects. River otters live an average of 8 – 9 years in the wild and 18 – 21 years in captivity. They are mature at two years of age. Females raise litters of 1 – 6 young in dens.
Habitat needs: Otters live near waterways, lakes, marshes, and coastal areas. They have adapted to living in a wide range of elevations and habitats. Their home range may be 15 square miles or more.
Status & conservation: By the early 1900’s, populations had decreased in large parts of their range due to unregulated trapping and development by settlers. More recently, their numbers were reduced due to habitat loss and pollution. Management efforts began in the 1970’s. They have been successfully reintroduced into 21 states where they once lived including parts of the Midwest. Populations are currently stable in much of their range.
Interesting facts: The nostrils and ear holes close when the animal submerges underwater. The right lung is larger than the left and this may help them adapt to living in the water.