Scientific name: Anser anser (Linnaeus, 1758)
Bird group: Geese
Field characters. 75-90 cm. A large, big-headed, thick-billed, heavy "grey goose". Greylag differs from other "grey geese" in absence of black on bright-orange bill, flesh-coloured legs, pale grey fore-wing and rump, head and neck not being darker than body, and underparts virtually without dark bars (though breast often with black spots and blotches). Two subspecies separable in Europe: western European form Anser a. anser with orange bill; East European form A. a. rubrirostris with pink bill and paler upperparts.
Voice. Like a farm-yard goose.
Distribution. Range once continuous, but now split into isolated small areas. Recently reintroduced in a number of localities. Very common breeding bird on Iceland.
Habitat. Breeding areas near extensive, open fresh waters with dense, emergent vegetation. In the breeding season frequents tundra, wetlands, swamps, heather moors, etc. Outside the breeding season on marshy grasslands, salt and fresh marshes, estuaries, floodlands, reservoirs; feeds also on fields with sprouting grain, stubble, or other cultivation.
Food. Feeds mainly by grazing on land on roots, tubers, green leaves, flower-heads, fruits. Also feeds while floating on water.
Eggs. Unmarked, ground colour creamy- white, becoming pale to dark brown or yellow during incubation. Texture smooth, not glossy. Shape subelliptical/long subelliptical. Size 85 x 58 mm (77-97 x 50-66), weight 149 g (122-179).