There have been several species of rodents introduced to Washington State, and some of them are likely to help themselves into your home or business if given the opportunity. One of the first steps to dealing with a rodent problem is knowing what you are up against. Here are some of the most common rodents you may encounter in Washington:

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Roof Rat (Rattus rattus)

The roof rat goes by many names―many of which are testaments to the many different places the rodent will infest. You may hear of them referred to as black rats, ship rats, house rats, and fruit rats. In our area, the name of “roof rat” is the name most commonly used. Adults are usually 5 to 7 inches long, and their nose is pointed. Coloration varies between dark brown to a lighter brown with a lighter underside. While they’re originally from Southeast Asia, they have spread all over the world thanks to their ability to tag along with humans as well as their commensal nature. Roof rats are good climbers and are commonly seen scaling trees to find food or shelter. Their climbing abilities are as adept as any squirrel, which can make it hard to stop them from finding ways into your home.

Norway Rat (Rattus norvegicus)

Norway rats are referred to by other names as well: sewer rat, street rat, brown rat, etc. In our area, the Norway rat is the most common name used. Larger and broader than the roof rat, Norway rats can reach up to 11 inches as adults, and their nose is blunter in shape than the roof rat. Coloration varies between brown to dark grey, with the underside being slightly lighter. Thought to be originally from China, they have managed to follow humans all over the world, and are considered one of the most successful mammals on the planet, alongside us. Essentially, this rat lives where we live, especially in urban areas.

House Mouse (Mus musculus)

Obviously much smaller than rats, house mice vary from between 3 and 4 inches as adults. Coloration varies but is commonly a nondescript gray. Prolific breeders, house mouse infestations can reach epidemic proportions in a short amount of time. This is because: 1) a single female can give birth to an average litter of 6 to 8 young and have 5 to 10 litters per year, and 2) Females reach maturity at about 6 weeks. Because they are so much smaller than rats, it is even more difficult to find and fix areas around a structure where they may be entering. Originally native to Asia, house mice have also become one of the most successful mammals in the world.

Deer Mouse (Peromyscus maniculatus)

The deer mouse is slightly smaller than the house mouse. Their coloration makes them easily distinguishable from a house mouse. It is normally dark brown in color but unlike the house mouse, all deer mice have a recognizable white underside as well as white feet. The deer mouse is radically different from the other rodents on this list because it invades homes at a fraction of the number of house mice or rats and is considered to still be relatively “wild” when it comes to living around humans. When they are found in structures, they’re most commonly found away from urban areas (such as wooded areas or areas that were recently previously wooded) in barns, garden sheds, and similar areas. They prefer to live outside—generally if they end up in a structure it may have been a timely opportunity seized upon by them to gain shelter.

How to Get Rid of Rodents in Washington State

Whitworth Pest Solutions can help you identify the rodents that are making themselves feel at home on your property. We perform a thorough inspection and analysis of the property to understand the scope of the problem, and then take corrective action. We monitor our efforts throughout the entire process to ensure our methods are having the desired effect. Once we’ve controlled an existing rodent problem, we establish preventative measures to keep them from coming back. Contact us to learn more or set up a free inspection today.