Norway Rat   Print   |  Home  |  Close Window
     
The brown rat, common rat, Hanover rat, Norway rat, Norwegian rat, or wharf rat (Rattus norvegicus) is one of the best known and most common rats, and also one of the largest. Thought to have originated in northern China, this rodent has now spread to all continents, except Antarctica, and is the dominant rat in Europe and much of North America. It lives wherever humans live, particularly in urban areas. It is a brown or grey rodent, with a body up to 25 cm (10 in) long, with the tail a similar length; the male weighs on average 350 g (12 oz) and the female 250 g (9 oz).

The fur is coarse and usually brown or dark grey, while the underparts are lighter grey or brown. The length can be up to 25 cm (10 in), with the tail a further 25 cm (10 in), the same length as the body. Adult body weight averages 350 g (12 oz) in males and about 250 g (9 oz) in females, but a very large individual can reach 500 g (18 oz). Rats weighing over 1 kg (2.2 lb) are exceptional, and stories of rats as big as cats are exaggerations, or misidentifications of other rodents such as the coypu and muskrat.

Brown rats have acute hearing, are sensitive to ultrasound, and possess a very highly developed olfactory sense.

Information Source / More Info:  Wikipedia.org