Biology of Norway rat

The Norway rat is known by many handles. . It is called the brown rat, sewer rat, rat, Norwegian rat, and wharf rat. Like most rats, they have coarse fur that is grey or brown on the backside and lighter color on the underside. Norway rats can grow up to 10 inches in body length; with a tail is the same length as its body the tail will be pink or brown in color, and bald. . Its tail is fatter at base tapering to a blunt point, is cylindrical, and scaly. Adult males typically weigh about 1.25 lbs, and females are half that. A Norway rat has a stubby, blunt nose, beady eyes, and small close-set bald ears.



This type rat is nocturnal, a good swimmer, and an excellent digger. Unlike black or brown rats, the Norway rat is a poor climber. Rats are capable of producing ultrasonic or sonic vocalizations. The “squeaks” we hear from rats are usually signs they are in distress.

Norway Rats are omnivores. This means they can prey on both plants and animals. This means seeds, fruits, garbage, pet food, insects, small invertebrates, carrion, and scraps. By nature, all rats are very opportunistic.

The Norway rat can breed year round if ample food, water, and shelter is available. a female produces 4 to twelve litters in a year. Gestation is 21 days, and litters can have up to 14 pups. Because of their ability to breed, rat populations can rapidly Norway rats live in large family, whether underground, or manmade places such as sewers and cellars. If food is in short supply, the rats at the bottom of social order are the first to die, and often become food. If a large percentage of the population is exterminated, the remaining rats will increase reproduction to restore the population level as quick as possible. This makes prevention and aggressive eradication so important. Eliminating the entire population and preventing re infestation is the only way to keep your home free.

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