The water rail (Rallus aquaticus) is a bird of the rail family which breeds in well-vegetated wetlands across Europe, Asia and North Africa. Northern and eastern populations are migratory, but this species is a permanent resident in the warmer parts of its breeding range. The adult is 23–28 cm (9–11 in) long, and breeds in reed beds and other marshy sites with tall, dense vegetation. These rails are vulnerable to flooding or freezing conditions, loss of habitat and predation by mammals and large birds. The introduced American mink has exterminated some island populations, but overall the species' large range and numbers mean that it is not considered to be threatened.