The river otter is found only in the USA and Canada. It is part of the Mustelide family. It is approximately 3–4 ft (1 m) long. They have a life span of 25 years in captivity and 15 years in the wild. River otters have been around a long time; fossils were found dating back to around 200 BC. They are excellent swimmers and divers and can swim at a speed of about 7 miles per hour (12 kph), rarely making a ripple or a splash. They have built in valves and flaps to making them watertight while under water. River otters plays more than other wild animals and they are most active at night. Their clawed and webbed feet are very good for running and swimming. The river otter’s coat can vary from a red to black. Their bellies are silvery or a red-brown. Their fur is the most durable in North America and has been in demand ever since the Europeans made contact. It is still-hunted for its fur today, in the last few years over 50,000 river otters were trapped and killed. River otters communicate using: chirps, chuckles, grunts, whistles, screams.
World Range & Habitat
River Otters do well in Alaska, Canada, and in the states along the Atlantic Coast. They have disappeared in nine states and in one Canadian province. They are very sensitive to changes to their habitat. The main reason why river otters have disappeared in so many places is habitat destruction. They use a variety of habitats: lakes, ponds, and marshes. The beaver makes ideal habitats for the river otter: a quiet, protected pond with an old unused den for the otter to use. River otters also require huge amounts of territory. In one year, a single otter may occupy over 50 miles (80 km) of a stream or a river at one point during that year. The river otter has a few natural enemies: wolves, foxes, and raptors.
Otters are carnivorous and feed on crustaceans, amphibians, reptiles, birds, insects, and most commonly, fish. They use their sense of touch to find and catch food underwater. Using their whiskers they can sense the movement of their prey to aid in catching it. They mostly hunt by diving and chasing in the water and digging in the stream bed. These techniques don’t always work though. A study found that otters diving for food had only a 20% success rate. River otters catch their prey in their mouths and hold them with their forelimbs. They eat their food headfirst and throw away the fish fins. After they are finished eating, river otters will clean their face and whiskers in the grass.
River otters usually travel in families but without the father, who rarely helps the mother rear the young. They reach sexual maturity at 2–3 years. They breed in March or April and birth takes place in the late winter or early spring. A litter can have one to six otter babies, or kits. The average litter has only two to three kits. The mothers are extremely devoted parents who teach the young to swim and catch prey by catching it and releasing for the young to catch. The kits grow fast and are roaming outside the den at two to three months. They can care for themselves at five or six months but they usually stay around until the next litter. They are 12 to 13 months old when they leave the den permanently.