The Norway Rat:  Most people regard all rats with disdain & fear and the Norway rat (or Brown rat) is the "granddaddy" of them all.  Norway rats are the most common in the world, and the only species found in the Quad Cities area.

Norway rats are very cautious, whereas mice tend to be more curious of new things in their environment.  That's one reason why rats are usually more difficult to control with traps or bait.  Their continual gnawing is destructive and rats are known carriers of diseases.  And like mice, rats are avid climbers and they also contaminate food with their droppings and urine!

Other critters such as shrews, moles & gophers are less invasive to homes.  But all rodents and critters have one thing in common: Regardless of their size, shape or species, people don't want any of them in their home!