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Rat Facts

Picture of a rat burrow under a fence between properties.

Where do rats live?

The most common rat responsible for residential infestations is the Norway Rat. These rodents prefer to live underground in burrows. These burrows are most often made alongside building structures, fence lines walkways patios sheds and under low decks.

What do they look like?

Adult Norway rats are 12 to 18 inches long with a tail five to eight inches long. Their fur is brown to reddish gray on their upper back and grayish white on the belly. They are heavy set with a sparsely haired tail, blunt nose, and short ears. Feces are capsule shaped and up to three fourths of an inch long.

Picture of a Norway rat.
Norway Rat

How long do they live and how often do they breed?

Rats typically live about one year, although they may survive longer, and females may have four to seven litters of young per year. Litters range from six to 12 with a total of about 30 young expected to live to maturity per year.

What are their Habits?

Norway rats typically live in burrows which are 12 to 18 inches below ground and under three feet in length. Burrow openings are three to 10 inches in diameter, roughly dug, with openings usually angled towards a sheltered area. There are typically clearly defined paths or ”rat runs” leading to the burrow openings. Rats will travel up to 150 feet to find a source of food. They are omnivorous or will eat their young if the need arises. They tend to grow in population in direct relation to the available food supply.

Picture of a rat burrow beneath a retaining wall.
Rat Burrow

 How does this affect the public?

Rats can destroy or contaminate food supplies. Rodent feces and urine are a source of gastrointestinal diseases such as Salmonellosis or E-coli infections, and respiratory diseases such as Hantavirus. The rat flea has been an important agent of transmission for Plague and Murine typhus.       

Revised February 13, 2013

Revised April 6, 2016         


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