Norway rats (or brown rats) are large rodents that may weigh in excess of 500 grams. They can reach lengths of 40 cm and their tails alone may measure 21 cm.
The Norway rat has shaggy, coarse fur that is coarse and usually brown or dark grey, while the underparts are lighter grey or brown. The brown rat is a rather large true murid and can weigh twice as much as a black rat and many times more than a house mouse. The length is commonly in the range of 20 to 25 cm (8 to 10 in), with the tail a further 18 to 25 cm (7 to 10 in), thus being roughly the same length as the body. Adult body weight averages 350 g (12 oz) in males and about 250 g (9 oz) in females. Their dropping are capsule-shaped.
Common places to find bug
Norway rats typically nest in underground burrows. They will enter buildings in search of food and often remain in hiding during the day.