The species of rat found in Chicago is the Norway rat.  The name is rather misleading as this species originated in Asia centuries ago.

The rat has an average life span of six to twelve months.  Beginning at the age of two to three months, a female rat can produce four to seven litters per year with each litter containing eight to twelve pups.  Females can become impregnated within 48 hours after giving birth.  The number, size and survivability of litters produced depends upon the amount of food and shelter available.

They prefer fresh food, but will eat many things such as pet food, dog feces, garbage and plants.  If food is scarce, the strongest rats may even eat the weakest and young.

Norway rats prefer to live in burrows in the ground.  They are excellent climbers and swimmers and most active at night.  They have very hard teeth and can chew through wood and plaster or any other material that is softer than their teeth.  They can crawl through holes the size of a quarter, tread water for three days and land unharmed after a five-story fall.

Norway rats live in colonies that have very well defined territories.  The strongest colonies get the best places to live.

The risk of disease being spread from rats to humans is very real.  By their very nature, rats carry a variety of potentially infected fleas and ticks which may be passed on to people. 

Both exterior and interior rat problems should be reported to 3-1-1 or click on the button below to submit a report online.