River Otters in or Under Buildings
Occasionally a river otter will find
a suitable den site in or under a building. Otters normally occupy a den site
for only two or three consecutive nights. However, during the mating and
nesting season, females are attracted to warm, dry, dark, easily defended
areas, and will remain longer if the setting remains favorable.
You may choose to let otters occupy an area, such as under an outbuilding, if they don’t pose a problem. Should you choose to remove the animals, a wildlife control company can be hired, or you can complete the process yourself using the steps below.
1. Seal all openings except the main entrance used by otters. Use sturdy wire mesh (1/4-inch hardware cloth or similar materials) to screen vents near ground level in houses and other structures. Tightly seal holes in foundations or under porches to prevent otters from entering.
2. To determine entry points, you can use "tracking patches" of a fine layer of sand, flour, or dust placed at suspected entrances. Wadded up newspaper lightly stuffed into the entry hole also works great. Otters will push the paper out of the way when exiting.
3. After dark, when the otter has left seeking food they will leave tracks at the den entrance. Inspect the powder or the dislodged newspaper for exiting otter tracks.
4. Once a otter has left the building, immediately seal the entrance with a hardware cloth "one-way door"(You will not want to permanently exclude at this point, not being sure of the number of otters present.) The one-way door can be made from 1/4 -inch hardware cloth that is attached over the opening, and hinged at the top and left loose on the other 3 sides. It should be larger than the opening so that it cannot swing inward. The otter will push it open to leave, but cannot re-enter.
5. Put a layer of flour on the inside and outside of the door after the one-way door has been installed for two to three nights. Any footprints in the flour should be outside the door with none inside. This means the otter is out. If you have any doubt, then smooth out the dirt on both sides of the door with your hand or a tool, reapply the flour and observe. Once a couple of days have gone by with no footprints, the skunk is probably gone. Another way to check is to open the door and shove a few pieces of wadded up newspaper into the otter’s entrance. If the paper stays in place for two to three nights, then the otter is gone.
6. Once you are sure all otters are out, permanently seal the opening.
Important Note: Be sure all animals are out before sealing up the entrance. Pay close attention and use extra caution if trying this option March through May when babies may be in the den.
You may choose to let otters occupy an area, such as under an outbuilding, if they don’t pose a problem. Should you choose to remove the animals, a wildlife control company can be hired, or you can complete the process yourself using the steps below.
1. Seal all openings except the main entrance used by otters. Use sturdy wire mesh (1/4-inch hardware cloth or similar materials) to screen vents near ground level in houses and other structures. Tightly seal holes in foundations or under porches to prevent otters from entering.
2. To determine entry points, you can use "tracking patches" of a fine layer of sand, flour, or dust placed at suspected entrances. Wadded up newspaper lightly stuffed into the entry hole also works great. Otters will push the paper out of the way when exiting.
3. After dark, when the otter has left seeking food they will leave tracks at the den entrance. Inspect the powder or the dislodged newspaper for exiting otter tracks.
4. Once a otter has left the building, immediately seal the entrance with a hardware cloth "one-way door"(You will not want to permanently exclude at this point, not being sure of the number of otters present.) The one-way door can be made from 1/4 -inch hardware cloth that is attached over the opening, and hinged at the top and left loose on the other 3 sides. It should be larger than the opening so that it cannot swing inward. The otter will push it open to leave, but cannot re-enter.
5. Put a layer of flour on the inside and outside of the door after the one-way door has been installed for two to three nights. Any footprints in the flour should be outside the door with none inside. This means the otter is out. If you have any doubt, then smooth out the dirt on both sides of the door with your hand or a tool, reapply the flour and observe. Once a couple of days have gone by with no footprints, the skunk is probably gone. Another way to check is to open the door and shove a few pieces of wadded up newspaper into the otter’s entrance. If the paper stays in place for two to three nights, then the otter is gone.
6. Once you are sure all otters are out, permanently seal the opening.
Important Note: Be sure all animals are out before sealing up the entrance. Pay close attention and use extra caution if trying this option March through May when babies may be in the den.
This information was provide by the Washington State Department of Fish and Wildlife, Russell Link, and Michael Holmquist
Click here to return to the home page
Click here to return to the home page
