The Black rat or Roof, Ship or House rat is the smaller of the two common rats and can be found in the subtropical and tropical regions of the world. They not only damage or destroy materials by gnawing, they eat and contaminate stored food. They are serious pests for farmers because they destroy crops too. The roof rat is also dangerous to humans because they can carry disease. In the United States, it is more common to see these rats in the coastal states, seaports, and the southern third of the country.
Brown Sewer Rat
The Brown Sewer rat or Norway rat is the largest of these rodents and the most common rat in the temperate regions of the world. It not only damages or destroys materials by gnawing, eating and contaminating stored food, but it is also dangerous to humans as a carrier of disease. They are found throughout the world as well as the U.S.