Norway Rat

The Norway rat is the largest commensal rodent in the US.

Identification

• Norway rats are usually gray in color

• Small ears

• Tail is short relative to the head and body

• Droppings are 3/4 inch and blunt on the ends

Environment

• Norway rats can exist in large numbers in and around residences, basements, stores, warehouses, docks, sewers, or dumpsters

• Burrow to make nests under buildings, beneath concrete slabs, around ponds, in and around garbage and other locations suitable for food, water, and shelter

• Nests may be lined with shredded paper, cloth or other fibrous materials
  Usually become active at about dusk to begin seeking water and food

• Eats nearly any type of food but prefers a nutritionally balanced diet, consisting of cereal grain, meats, fish, nuts, and some fruits

Threats

• Norway rats like to burrow and can form extensive galleries

• Have litters of 6 to 12 young that can eat solid food within 2 to 3 weeks

• Young become completely independent at about 4 weeks and reach reproductive maturity as early as 3 months

Treatment

• Traps placed indoors near entrance points and known runways

• Burrows outdoors may be baited

• Exterior bait stations may be placed on the perimeter of the structure