River otters are brown and black.
The adults are three to four feet long, including their 12 to 18 inch tail.
The tail is flat and well muscled. They generally weigh 15 to 25 pounds.
The males are usually larger than the females. The river otter's
body is elongated. It has small ears. Its ears and nose close when it goes
under the water. Its eyes are located near the top of its head, so it can
see above the surface while it is swimming nearly submerged. The river
otter's legs are short, with five webbed toes on each
foot. It has tightly packed underfur, and its long
guard hairs are water-repellent. It has teeth like a carnivore. The
otter's sense of smell is very good, but its senses of sight and hearing
are not as well developed.
The North American river otter can be found in Canada and the United States. Otters are well adapted for aquatic life and are usually found in or near water. They can be found in marine and fresh water environments. They are found in rivers, lakes, marshs, and other inland waterways. They prefer the tributaries of major, unpolluted bodies of water where there is very little human disturbance. Log jams and submerged trees provide a resting place for them. Otters live in dens underground. Otters rarely dig dens themselves. Instead, they make their homes in abandoned beaver lodges and homes built by other animals, such as woodchucks. Brush piles, root areas under large trees and similar sites are used as temporary homes.
The river otter's facial whiskers are extremely sensitive to touch, so it is able to locate food even in muddy water. In the wild, river otters eat fish, freshwater mussels, frogs, turtles and water birds. They also eat crayfish, rodents, snakes, as well as aquatic bulbs, roots and blueberries. Fish is their favorite. At the zoo they eat smelt, omnivore biscuts, feline diet, and eggs every day.
River otters are solitary creatures, except when they pair up during mating season. Breeding occurs during early spring following the birth of a litter. When the young are born there are usually two. Litters are cared for by the mother. New born pups have silky black fur. They are toothless, blind and helpless. The pups weigh four to six ounces and are eight to eleven inches long at birth. Pups grow rapidly and emerge from the den at two months old. They eat solid food at two months and are weaned at three months. Young otters are self sufficient by the time they are five to six months old. The family group remains intact for at least seven or eight months or up until the birth of a new litter.
Otters are expert swimmers and divers. They can swim at an average speed of seven miles per hour and stay underwater for up to 2 minutes. Otters seem to like to play more than other wild animals. They often wrestle and chase each other. They like to slide down wet banks and over the snow. River otters are most active from early evening through early morning. They are active all year, even in the coldest of weather. A fat layer under the skin and its dense, oily fur protect the otters in extremely cold water.
Otters communicate with their noses, mainly by smelling marked territories. When they do talk, they use chirps, chuckles, whistles, and screams.
River otters have been reported to live nearly 25 years in captivity and about 15 years in the wild. They have few natural enemies, especially while they are in water. Humans are their biggest enemy. In order to protect the river otter we need to protect its habitat. We must keep pollutants out of our rivers, lakes, etc. This can be done by stronger regulations by our government on companies that dump pollutants into are waterways. We need to protect the otter from fur trappers by outlawing the killing of otters. If we don't, the otters might not even survive the 20th century.
The otters at the Brandywine Zoo are Jester and Delta. Jester is a 9 year old male and Delta is a 9 year old female. Jester came from the Beardsley Zoo. Delta came from a Louisiana breeder. Both were approx. 1 year old when they came to the zoo.The Brandywine Zoo otters became sexually mature in 1999. Jester is after Delta, but she is not interested. Their favorite activities are climbing and destroying anything they can. They also like to steal stuff when the zoo keepers aren't looking.
For more information:
http://www.ngpc.state.ne.us/wildlife/otters.html
http://www.luddist.com/otter.htm
http://www.nature.ca/notebooks/english/rivotter.htm
http://www.otternet.com/ROA/
http://www.pbs.org/wnet/nature/otters/river.html
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by Josh