The Black Rat (Rattus rattus), also known as the Asian Black Rat, Ship Rat, Roof Rat or House Rat, is a common long-tailed rodent of the genus Rattus (Old World rodents). The species originally came from the tropical areas of Asia, but eventually spread throughout the Near East in Roman times before reaching Europe by the 6th century and spreading with Europeans across the world. Today, however, it is again largely confined to the warmer climates, having been supplanted by the Brown Rat in cooler regions.
Despite its name it comes in several color forms. Compared to the Brown Rat, it is a poorer swimmer, but more agile and a better climber, tending even to flee upwards. It is usually black to light brown in color with a lighter underside. A typical rat will be 6 to 8 inches long with a further 8 inches of tail. It is nocturnal and omnivorous, with a preference for grains.
In a suitable environment it will breed throughout the year, with a female producing three to six litters of up to ten young. Females may regulate their production of offspring during times when food is scarce, throwing as few as only one litter a year. Black rats live for about 2-3 years and sometimes can be found in social groups of up to 60 members. The Black rat has been known to fall victim to a number of diseases, such as bubonic plague, typhus, toxoplasmosis, and trichinosis are the most well known.