The Brown Rat, Rattus norvegicus, is also referred to as the Common Rat, Street Rat, Sewer Rat, or Norway Rat. This species is commonly found in urban and suburban areas. Rats can often be distinguished from other small mammals in camera trap images by their size and long, hairless tail. They will be smaller than muskrats, larger than mice and voles. Remember that if you are not certain of the identification of a small mammal, you may use the tag "small mammal (cannot ID)" to indicate that.