The Clown Of The Waterways Has Returned!
By Jim Evans
It was at least three feet long – the biggest mink I've ever seen. I watched it play in the water alongside my canoe for a good 10 minutes,” explained the animated voice on the telephone. Since completion of the program to return the river otter to its native habitat in the Mountain State, Division of Natural Resources personnel have received many calls about the otter each year. Each caller is very excited about a unique experience in the wilds of West Virginia.
The river otter historically lived throughout most of North America, from northern Mexico to the Arctic Circle and from the Atlantic Ocean to the Pacific Ocean. By the early 1900s, however, it was absent from much of its historic range, a victim of stream pollution and unregulated trapping. As our larger rivers became polluted and the fish disappeared, so did the river otter. Acid mine drainage was devastating to otter habitat in West Virginia. Good otter habitat was also good beaver habitat, and otters were often caught along with beaver. As the beaver disappeared in the quest for fashionable “felt hats,” so too did the otter.
West Virginia, being the last frontier in the East, was one of the last states to see the otter extirpated. A few river otters were found in the South Branch of the Potomac in Grant and Pendleton counties and Red Creek in Tucker County as late as the 1950s. Although the state legislature gave the river otter total protection in 1925, populations were too low for this colorful clown of the waterways to survive.
As stream pollution in the East and mid-West states abated and fish and other aquatic organisms returned to our rivers and wetlands, many state wildlife agencies began to explore the possibility of reintroducing the river otter back into their native habitats. West Virginia was one of the first states to successfully reintroduce the river otter. From 1984 to 1997, DNR personnel reintroduced 245 otters into 14 major rivers of the state.
Otters were obtained from Maryland, Virginia, North Carolina and Louisiana. Most otters were caught with soft-catch foothold traps and transferred to holding facilities for one to two weeks before being transported to West Virginia . Most were caught by trappers in these states. They were routinely given a health check, vaccinations and released back into the wild within 24 hours. Studies conducted early in the release efforts by West Virginia University graduate students indicated that otter populations were doing well.
The river otter is the largest member of the weasel family found in West Virginia. Other members of the weasel family living in the state include the mink, long-tailed weasel, least weasel, striped skunk, spotted skunk and fisher (which was also reintroduced into West Virginia).
Adult males are about 1/3 larger than adult females, weighing from 10 to 25 pounds and stretching 35 to 60 inches from the head to the tip of the tail. An otter's body, muscular and torpedo-shaped, allows it to swim swiftly and easily through the water. The stout tail, making up about 1/3 of the total body length, is used as a rudder while swimming. The head is broad and slightly flattened, with a large nosepad and stiff bristly whiskers used in locating prey. The otter has small black eyes and small rounded ears. The short legs are equipped with five fully webbed toes on each foot that propel the otter in its aquatic home. The fur is dark brown to reddish brown on the back with a light brown, tan, or silver color on the throat and belly. The otter's dense, oily underfur overlaid by glossy guard hairs makes it well suited for thermal regulation.
The river otter, a carnivore, is well adapted to catching food in its aquatic habitat. Crayfish and rough fish such as carp and suckers make up the largest part of the diet, but they readily eat frogs and muskrats. Of course, the otter will take game fish, as several trout pond owners have found out. Otters tend to catch the first fish available so they will normally select the slowest moving prey. This is why suckers and other rough fish are primary items on their diet.
An amusing incident occurred when the DNR decided to pursue an otter reintroduction study. An article was written about the otter study in Wonderful West Virginia magazine. The editor, needing a picture of an otter to go with the article, found a picture of an otter sitting proudly on an ice-covered stream eating a five-pound large-mouth bass. Obviously, the article didn't endear the otter to Mountain State bass anglers.
Otter scats are often found in “toilet” areas located on high banks, islands and points along river banks. Scat often contains fish scales and crayfish remains. Biologists study these toilets to determine the presence of otter and to document food habits.
Adult river otters normally breed in the spring, with estrous periods of 42 to 46 days. The female otter may advertise her estrous condition by marking at scent stations and takeouts such as river slides. The male otter is an aggressive mate but is solitary and does not form a pair bond with the female. After mating, the males abandon the females. Pregnant females have a gestation period of 288 to 375 days. A phenomenon common to many members of the weasel family called “delayed implantation” occurs, in which the development of the blastocyst is delayed until it implants into the wall of the uterus. The actual birth takes place 60 to 63 days after the implantation of the blastocyst. This allows the birth to occur the following year at a better time for survival of the young.
Pregnant females usually go to remote natal areas, such as a small tributary of a larger stream, to give birth. Otters often use an abandoned beaver house, a burrow of some other animal, a cavity among streamside roots or a logjam for their natal dens. Peak rates of birth occur in March and April. Litters average two to three silky black, blind, helpless pups which are totally dependent on the mother otter. After birth the female otter moves her young to an area of abundant prey where the young otters can develop. The pups stay with the mother from seven to eight months and then disperse on their own. The siblings often remain together for the first year.
Otter populations are not high even in good habitat. One family group per 10 or 20 miles of stream is considered a good population. River otters are generally nocturnal or crepuscular, so early morning or late evening is the best time to see them. They often congregate around activity centers with abundant food and cover. Pools below dams, oxbows, islands and riffles that stay free of ice offer good places to see otters. Intelligent, active and inquisitive, otters spend much of their time exploring new surroundings and objects. Their ability to make a game out of any activity is almost legendary. They are noted for their playful behavior and habit of sliding down steep river banks. They have a bounding or loping gait on land and their distinctive bound and slide mode of travel on snow is unmistakable. Curious and near-sighted, they often approach within a few feet of a boat or person on shore.
Ten years after completion of the otter releases, DNR personnel needed to know the river otter's status in West Virginia. During earlier studies the otters were monitored using telemetry transmitters and receivers to determine locations, movements and mortalities. Bridge surveys and observations were used to determine their status during the later studies. Biologists surveyed stream banks around selected bridges for three consecutive years. They found otter sign at 19 percent of bridge locations throughout the state.
Since the river otter was extirpated from much of its native range in North America, 21 states and one Canadian province have successfully reintroduced the otter. What does the future hold for the river otter in West Virginia? The otter seem to be doing well; however, there are several more streams and rivers where otter may eventually become established. These include the Potomac, Monongahela, Ohio, Kanawha and Big Sandy rivers.
The otter is a valuable furbearer species. In North America 50,000 otters were sold in the 1970s at a price of about $3 million. Trapping is currently prohibited in West Virginia to allow the otter time to repopulate their native streams. Since otters may also enter beaver traps, many trappers modify their underwater traps to allow otter to go through the trap without harming them.
Why did the DNR return the otter to its native home? Ask any angler or hiker who has seen an otter. Ask a beaver trapper who carefully modifies his set to avoid catching the otter peering at him through a hole in the ice. They will all tell you that West Virginia 's pristine streams and mountain valleys are not complete without the clown of the waterways.
Jim Evans is supervisor of Game Management Services and stationed in Morgantown.