Of the over 20 species of rodents in B.C., only 3 are regarded as serious pests. They are the Norway Rat, the Black Rat and the House Mouse. If the rat or mouse problem is identified and resolved quickly there is very little likelihood that the problem will re-occur. If, however, they are allowed to establish themselves they can be very difficult to get rid of.
Norway rats prefer moist conditions and are generally found at ground level, crawl spaces or in burrows around buildings. They weigh up to 0.5kg. (1lb.) and are easily identifiable by their blunt nose, small ears and shorter than normal tail. Norway rats have exceptional climbing abilities giving them access to almost anywhere in a building. They can produce up to 7 litters of 8-12 pups per litter per year making them a real concern, should they become established in an area or building. Like mice, they can cause extensive damage to buildings chewing on the materials used in their construction.
The Black Rat differs from the Norway Rat in features and area of habitat. Black rats are slimmer, have larger ears and tails that are longer than the body and head combined. They nest in ceilings, attics and upper spaces in buildings and, like the Norway Rat, is an excellent climber.