How to Scare off Northern River Otters

Northern river otters rarely conflict with humans.

Northern river otters are widespread in North America, with populations in many areas recovering from excessive trapping, water pollution and other human influences that provoked declines in the 18th and 19th centuries. Intelligent and adaptable members of the weasel family (or mustelids), river otters are important in the continent's freshwater ecosystems, functioning as top predator across much of their range. They avoid humans, but occasionally become a problem if they raid trout ponds or hatcheries or, more rarely, target poultry. Repelling them non-lethally is the best way to ward them away while encouraging their continued function in the local ecology.

Instructions

1. Frighten otters away from fish pools or other areas you wish to protect. This will likely take nothing more than approaching the animals; like most wild carnivores, otters shy away from humans and tend to flee if encountered. Shouting and clacking objects together should reinforce otters' natural aversion and ingrain a negative association to the area.

2. Fence off ponds. Enclosures needn't have particularly high walls, because otters do not typically jump much, but the material should be a strong one, such as durable wood or well-meshed wire. Sink the fence underground or reinforce the fence bottom with a wire apron to prevent the otters from digging or squirming underneath.

3. 

   Fencing off crevices in outbuildings may discourage otter denning.

   Locate potential denning sites in the vicinity of the pond or structure you're protecting and block them. Crevices beneath buildings or natural cavities in banks may attract a female otter looking for a place to bear her young, and an adult otter caring for offspring may be more likely to investigate human food sources. Use wire, lumber or other firm material to seal off such an opening before otters discover it.

4. Rig lighting around your pond. An investigating otter may be frightened off if it triggers a security light. Especially in areas with substantial human activity, river otters often favor nocturnal activity, making this particularly appropriate.

5. Create an environment inhospitable to otters through other creative means. A leashed large dog will usually deter otters, which naturally compete with and avoid coyotes and gray wolves in the wild. Playing loud recorded music near a fish pond may also do the trick.

Tips & Warnings

• Contact your local fish and wildlife department if you are experiencing chronic problems with river otters. Such professionals can offer advice or, if necessary, implement proper and legal mitigation efforts such as live-trapping and removal.

References

• Washington Dept. of Fish & Wildlife: Living with Wildlife - River Otters

Resources

• University of Michigan - Animal Diversity Web: Northern River Otter
• West Sound Wildlife Shelter: River Otters