The greylag goose (Anser anser) is a species of large goose in the waterfowl family Anatidae and the type species of the genus Anser. It has mottled and barred grey and white plumage and an orange beak and pink legs. A large bird, it measures between 74 and 91 centimetres (29 and 36 in) in length, with an average weight of 3.3 kilograms (7.3 lb). Its distribution is widespread, with birds from the north of its range in Europe and Asia migrating southwards to spend the winter in warmer places. It is the type species of the genus Anser and is the ancestor of the domestic goose, having been domesticated at least as early as 1360 BC. The genus name is from anser, the Latin for "goose".
Greylag geese travel to their northerly breeding grounds in spring, nesting on moorlands, in marshes, around lakes and on coastal islands. They normally mate for life and nest on the ground among vegetation. A clutch of three to five eggs is laid; the female incubates the eggs and both parents defend and rear the young. The birds stay together as a family group, migrating southwards in autumn as part of a flock, and separating the following year. During the winter they occupy semi-aquatic habitats, estuaries, marshes and flooded fields, feeding on grass and often consuming agricultural crops. Some populations, such as those in Southern England and in urban areas across the species' range, are primarily resident and occupy the same area year-round.
Greylag geese are largely herbivorous and feed chiefly on grasses. Short, actively growing grass is more nutritious and greylag geese are often found grazing in pastures with sheep or cows. Because of its low nutrient status, they need to feed for much of their time; the herbage passes rapidly through the gut and is voided frequently. The tubers of sea clubrush(Bolboschoenus maritimus) are also taken as well as berries and water plants such as duckweed (Lemna) and floating sweetgrass (Glyceria fluitans). In wintertime they eat grass and leaves but also glean grain on cereal stubbles and sometimes feed on growing crops, especially during the night. They have been known to feed on oats, wheat, barley, buckwheat, lentils, peas and root crops.
(latin: Anser anser)
