How to Avoid a Rat Infestation

Washington state is home to a variety of native and non-native rats. There are rats living at the edges of our community, but there are some steps you can take to reduce their presence in the neighborhood.

From the Washington State Department of Fish and Wildlife Website:

Washington is home to both native and non-native rats, the latter sometimes being referred to as Old World rats.

Food and Feeding Behavior

• Old World rats will eat anything humans or livestock will eat, plus many less palatable items including animal droppings, garbage, and other rats.
• Rats begin foraging soon after dark and most of their food gathering occurs before midnight. They often store or hoard food in hidden areas.
• The main constraint of rats is they cannot live long without water if their diet doesn’t contain adequate amounts of liquids.
• Food items in household garbage offer a fairly balanced diet and also satisfy their moisture needs.

Old World rats are active all year, mostly at night. However, when disturbed (weather change, construction, etc.), hungry, or when living in crowded conditions they are seen at any hour. It is not easy to tell how many rats are using an area. However, you can use their signs as a rough guide to whether the population is low, medium, or high. Use a powerful flashlight to search for their sign in dark places and to spot the animals after dark. In a medium-populated area, droppings and gnawings can be found, and rats will be heard in or under a structure at night. In addition, cats and dogs may excitedly probe an area of floor, wall, or other area where rats are present, especially if rats have only recently entered.

Preventing Conflicts

In the process of seeking food and shelter, Old World rats can contaminate human or domestic animal food with their droppings, destroy insulation, and create noise in attics, walls, and crawl spaces. Rats also chew on electrical wiring and structural supports in buildings.

Rat populations may be a consequence of community-wide activities over which you have little control—improper garbage disposal, building demolition, and poorly maintained bird-feeding stations. The following recommendations ideally should be followed before rats enter areas where they are unwanted and before the numbers of rats become extreme.

1. Prevent access to food and water.
2. Store human and animal food in rat-proof rooms or containers.
3. Prevent raccoons and other animals from making garbage available. Keep your garbage-can lid on tight by securing it with rope, chain, bungee cords, or weights. Better yet, buy garbage cans with clamps or other mechanisms that hold lids on. To prevent tipping, secure side handles to metal or wooden stakes driven into the ground. Or keep your cans in tight-fitting bins, a shed, or a garage. Put garbage cans out for pickup in the morning, after raccoons have returned to their resting areas.
4. Prevent access to fruit and compost.
5. Pick up fruit that falls to the ground. Don’t allow garden produce to rot on the vine. Compost it, or rototill or dig it into the soil.
6. Feed dogs or cats inside and clean up droppings.
7. Prevent access to bird feed and feeders.
8. Eliminate access to water.
9. Prevent access to shelter.
10. Prevent rats from climbing buildings.

For more information regarding procedures that prevent rats, see the Washington Fish and Wildlife website.