The Greylag Goose (Anser anser) is a bird widely distributed throughout the Old World, breeding wherever suitable habitat can be found in many European countries. The one exception to this is southwestern Europe, where it no longer breeds. It extends eastward across Asia to China. In pre-Linnean times it was known as the Wild Goose (anser ferus).
The Greylag Goose prefers to breed in variety of wetlands including marshes, lakes, and damp heather moors.
This large goose measures an average of 74-84 cm long and has a wingspan of 149-168 cm. It has a large head and almost triangular bill. The legs are pink, and the bird is easily identified in flight by the pale leading edge to the wing.
The western European subspecies, A. a. anser, has an orange-pink bill and is slightly smaller and darker than the pink-billed Asian race, A. a. rubrirostris. Eastern European birds are often intermediate in appearance. Its call is loud cackle “kiYAAA-ga-ga,” like the domestic goose.
This species is known to be the predecessor of domesticated geese found in Europe and North America. Flocks of feral birds resulting from domesticated birds are quite common.
This migratory species moves south or west in winter. Scottish breeders, as well as other populations in northwestern Europe, and feral flocks are largely resident. This species is one of the last to migrate, and it is thought that the English name signifies late, last, or slow, as in laggard, a loiterer, or old terms such as lagman, the last man, lagteeth, the posterior molar or “wisdom” teeth (as the last to appear), and lagclock, a clock that is behind time.
The Greylag Goose is also known as the grey goose, which in England when the name was given, was not strongly migratory but lagged behind the other wild goose species when they left for their northern breeding quarters.
Within science, the Greylag goose is most known for being the bird with which the ethologist Konrad Lorenz first did his major studying into the behavioral phenomenon of imprinting.