River Otter Fact Sheet


HISTORY

The river otter (Lutra canadensis) is a member of the Mustelidae or weasel family. It is an amphibious member of this family as are the mink and sea otter. While many states experienced declines in river otter densities, distribution, and in some cases extirpation in the mid 1800s - 1900s, Georgias population remained fairly widespread throughout much of the state. Today, the river otter thrives throughout the state, including areas in north Georgia where its populations were once diminished. River otter abundance is directly dependent on habitat quality and availability.

DESCRIPTION

River otter are thickly furred and their body is torpedo shaped. Their fur is usually dark brown but may range from almost black to reddish. The belly is usually silvery or grayish brown and their throat and cheeks are silvery to yellowish brown. Otters range in size from three to almost five feet long from nose to tip of tail. They may weigh from 15-30 pounds. Females are typically twenty-five percent smaller than males. Its tail makes up almost 1/3 of the length of the otter and is flattened to aid in swimming. The hind feet of the otter are webbed and the ears and nose have valves that close when the otter submerges to make the otter watertight. The otter can stay submerged for up to 4 minutes and dive to depths of 60 feet. It can swim at an average speed of 6-7 miles per hour and run up to 15-18 miles per hour.

HABITAT AND HOME RANGE

River otter are most active early evening through early morning and occupy a wide variety of habitat types in Georgia. These include lakes, ponds, marshes, rivers, and streams. River otter, especially males, may occupy up to 50 miles of a stream throughout the course of a year. Females generally have much smaller home ranges and may range over as little as 7 miles of a stream. River otter primarily use waterways as travel paths but do cross-land between rivers or streams or ponds and often have well worn paths, which are regularly used by otters for years. Otter use scent posts along these paths and waterways to mark territories and communicate with other otter in the area. Chirps, chuckles, grunts, whistles, and screams are also used by otter for communication.

DIET

River otters are carnivores and eat a wide variety of prey items depending upon location within Georgia and the time of year. Prey items along the coast may include crabs and young alligators while otter in middle to north Georgia may dine on muskrats. Common items eaten by otter throughout Georgia include various crustaceans, amphibians, reptiles, birds, insects, and fish. The most common prey item for otter is fish. River otter use their whiskers and keen sense of touch to find and catch prey with their mouth. They hunt by diving and chasing fish or digging in the bottom of ponds and streams.

BIOLOGY

River otter reach sexual maturity when they are 2 years old. Breeding takes place in March - April and the young, called "kits", are born the following late winter / early spring. This late birth is due to delayed implantation. Litter size can range from 1 - 6 but the most common litter size is 2-4. The young are usually born in underground dens that may be old beaver dens or washed out areas in river or stream banks. The kits eyes open when they reach around 5 weeks of age and first leave the den at around 2 months old. The male otter offers no assistance in raising the kits, but the female teaches the young to swim and catch prey. While the kits are weaned by 4 months of age, they generally remain with the female until they are 12-13 months old.

ECOLOGICAL IMPORTANCE

River otter are an important indicator species as to the quality of habitats where they are found. This is because the otter is a strict carnivore and contaminants that occur in the environment may concentrate in the otter over time in a process known as biomagnification.

NUISANCE

River otter sometimes cause nuisance problems for pond owners and commercial fish farmers. Because otter may often be found in family groups, they can clean out a small catfish or bass/bream farm pond in a short time. The only solutions are to let the otter have all the fish they want, prohibit entry through electric fencing, or lethal removal (preferably during the regular trapping season). River otter are rarely suspected in other types of nuisance complaints.

FURBEARER VALUE

River otter are a valuable furbearer resource worldwide. Georgias trapping season typically runs from December 1 through February 28 each year. Traps most commonly used for otter include conibears or body-gripping traps and footholds. A commercial trapping license is required to trap and sell river otter pelts but landowners may apply for a free trapping license to trap on their own land. River otter fur is used primarily for clothing, especially jackets and coats.

(from the georgia department of natural resources)