The mute swan (Cygnus olor) belongs to the genus of swans (Cygnus) within the family of waterfowl (Anatidae) and the subfamily of geese (Anserinae). This bird species is semi-domesticated and widespread in Central Europe. It prefers lakes, park and fishponds, shallow bays, and open river courses in winter. The species is named after the black knob at the base of its bill. Swans have few natural predators in Central Europe, but mute swans are a huntable species in Germany, with several thousand shot every year. The strong territoriality of the swans during the breeding season and losses during severe winters contribute to the regulation of the population.