River otters well adapted for semi-aquatic living

At first I couldn’t believe my eyes. I thought, “Wow, that is a really big muskrat; the way they moved in the water, they looked like small seals and then I saw two more heads bobbing up and down.”

I was walking my dog, Tessie, beside the Deep Creek boat dock where it meets the Kootenai River. I kept studying the four animals as they moved up the far side of the creek, I could see that they were strong swimmers and they were hurrying upstream in their journey. I rushed for my camera inside the Jeep out of anticipation that they were a family of otter.

As I focused my 600mm camera lens on the mother who was watching me, I could identify she was indeed a river otter. They were entertaining me with their playful antics, rolling over and diving, then the mother barked and they all disappeared under the water. I’ve been here 16 years and have only seen a handful of otters in Boundary County.

These playful mammals are well adapted for semi-aquatic living. River otters are members of the weasel family, whose luxurious pelts once made them staples of the Western fur trade. They have thick, protective fur to help them keep warm while swimming in cold waters. They have short legs, webbed feet for faster swimming, and a long, narrow body and flattened head for streamlined movement in the water. A long, strong tail helps propel them through the water and they can stay underwater for as much as eight minutes. They are very flexible and can make sharp, sudden turns that help them catch fish. Their fur is dark brown over much of the body, and lighter brown on the belly and face. On land they can run at speeds of up to 15 miles per hour and they can slide even faster.

Adult males average 4 feet in length, including the tail, and weigh 20 to 33 pounds. Female adults are somewhat smaller. Litter size is 2 to 4 pups. The habitat of the river otter includes lakes, rivers, creeks sloughs and ponds.

Though otters spend most of their time in the water, they’re also adapted for land travel, sometimes building their dens a half-mile away from the water. Otters are often photographed floating on their backs, and they’re known for their group play, which includes chasing each other. They’re cute and fun to watch, but don’t presume they’re like a puppy dog.

Otters are opportunistic eaters that will consume a variety of aquatic wildlife, such as fish, crayfish, crabs, frogs, birds’ eggs, birds and other reptiles such as turtles. They have also been known to eat aquatic plants and to prey on other small mammals, such as muskrats or rabbits. They have a very high metabolism so they need to eat frequently. They live 8-9 years in the wild but have lived up to 21 years in captivity.

I’m curious about what will happen over the winter. Late fall is typically the time when juvenile otters leave the family in search of their own territory. The family of otter will split and eventually start new families in the area.

The Kootenai River is part of our lives in Boundary County, to see these four otter has been really special.