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North American river otters are a fascinating species. They are renowned for their sense of play. The internet is peppered with amateur and professional videos chronicling their exploits, and many zoos have educational river otter exhibits. North American river otters have an estimated total population of over 100,000. About 10% of that total number now reside in Missouri.


Otters in Missouri

In 1982, the Missouri Department of Conservation started releasing river otters around the state in an attempt to bolster a population estimated at less than 100 animals, concentrated in the bootheel region of the state. Over the next 11 years, 845 otters were released. Because of these efforts, otters now exist in every county of the state, and the statewide population numbers peaked between 15,000-18,000.


Physical Features of North American River Otters

River otters belong to the weasel family. They can weigh between 11 and 31 pounds, and their length, including the tail, can exceed 5 feet. Otters have long bodies and short legs with webbed toes.

Otters prefer to eat fish

River Otters prefer to eat fish



In Missouri, river otters primarily eat crayfish from April through October. However, during the winter months (when fish populations are vulnerable) otters prefer to eat fish. They especially target hand-fed catfish, however they can also decimate populations of other popular fish. River otters are some of the world’s most efficient predators of fish, and they eat between 2 and 3 pounds of fish per day. In fact, they are so efficient at killing fish, that at times they will kill many more than they eat, leaving the evidence of their rampage on banks and docks for owners to discover.



In Missouri, otters live in a variety of areas statewide. Their only requirement is some kind of wetland, waterway, lake, or pond to provide them with their natural diet of fish and crayfish. Otters will travel long distances over land between bodies of water. They have few natural enemies, and adults are formidable fighters, so conservation population control is almost exclusively accomplished through trapping.


Otter on dock

Otter on dock

Breeding and Social Structure

Otters are very social, and will often stay with their mother until she gives birth again the following year. Siblings will often stay together for months after leaving their mother. River otters will breed in February or March, about two weeks after giving birth. However, they have what is known as a “delayed implantation” pregnancy, and the fertilized eggs are only implanted about 2 months prior to giving birth.




Fun Facts

  • “Otter” comes from an Old English word related to the Greek word hudros, meaning “water snake.”
    Otters leave fish head on docks

    River Otters leave fish carcasses

  • River otters communicate with a variety of sounds and scents.
  • River otters can remain underwater for an impressive 8 minutes at a time.
  • River otters use their specialized vision, acute sense of smell, and whiskers to track prey underwater.
  • River otters love to do somersaults, wrestle, flop, and slide around during playtime.
    Designated “latrine” areas

    Designated “latrine” areas

Signs of Otters

  • sighting an otter
  • dot-dot-dash track pattern on snow or mud from bounding and sliding
  • designated “latrine” areas
  • balled up grass and leaves in “wallows”
  • fish carcasses


Nuisance River Otter trapping

Trapping Nuisance River Otters

Risks Associated with Otters

The largest area of concern with otters is the potential of losing hundreds to thousands of dollars worth of privately stocked fish in ponds around the state. They can also significantly lower fish populations in public fishing areas.

If you are having problems with otters on your Lake of the Ozarks area property, call the professionals at Adair’s Animal Nuisance Trapping. Adair’s can remove nuisance otters in the water at any time of year, however we offer an otter maintenance program to trap nuisance otters during the winter months when fewer lakeside activities will be interrupted. Our experienced team of trappers will help make sure your favorite fishing hole doesn’t become a family of otters’ favorite restaurant.

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