Norway rats usually construct nests in below-ground burrows or at ground level. Nests may be lined with shredded paper, cloth, or other fibrous materials. A litter of 6 to 12 pups is born about 22 days after conception. Newborn rats are born hairless with flesh as pink as bubblegum. They are born with their eyes sealed shut and legs underdeveloped. They can survive on their own after a month and reach reproductive maturity at the end of three months. Breeding often peaks in spring and fall with reproductive activity declining during the heat of the summer and often stopping in the winter. The average female has 4 to 6 litters per year and may successfully wean 20 or more offspring annually. Most rats die before they are one year old.
To learn more about the breeding habits of rats and how to prevent rodents from invading your home, contact Cowleys Pest Services. Our pest control services are available in Lakewood, Woodbridge, Edison, New Brunswick, Jackson, Fair Haven, Asbury Park, Howell, East Brunswick, Perth Amboy and nearby New Jersey.