( Latin: Rattus rattus)
This rodent probably originated in south-east Asia, whence it has spread to large areas of the world. It arrived in Europe early in the Middle Ages and became very widespread until it was largely replaced by the brown rat. Black rats were responsible for spreading plague (Black Death) in Europe during the Middle Ages.
In most parts of Europe black rats have been completely eliminated, but they continue to arrive in ships from overseas and are therefore still present in certain large ports. They are associated with man to an even greater extent than the brown rat, but being more warmth-loving they do not occur out in the open in central and northern Europe.
When black and brown rats are living in the same building, the former keep to the upper storeys, while the brown rats live on the ground floor and in the cellars. The black rat can live in much drier places than the brown rat, and it jumps and climbs better. It can, for example, walk along a telephone line between one house and another.
Like the brown rat the black is essentially a social animal which lives in groups. It is not as prolific as its relative and it produces fewer and smaller litters.
Black rats are omnivorous, but they prefer a vegetarian diet, particularly cereals and seeds.