The geese arrive at the end of February in large flocks, with courting beginning in March and April. Warmer winters and green fields for most of the year have meant that the populations of both non-migratory and breeding birds have risen markedly in recent years in Denmark. The greylag goose is found in a broad swathe across the northern hemisphere, with the birds migrating north every year to breed. When a flock of hungry geese lands on the fields, they can wreak havoc on the crops, so in many places, permission is often sought to regulate the greylag in order to minimise crop damage. The herbage passes rapidly through the gut, and they therefore produce large amounts of excrement, which is far from popular in parks and on playing fields. Newly cut grass is also part of their menu, and flocks of greylags can often also be seen in parks.īecause there are few nutrients in grass, geese have to spend a lot of time foraging. Short, actively growing grass and grain is more nutritious than old grass, so greylag geese can often be seen grazing in pastures with sheep, horses or cows. Greylag geese are herbivores and feed chiefly on grasses. After two months, the chicks are fully-fledged, which coincides with the adults regaining their ability to fly after moulting their main wing and tail feathers a month earlier. The incubation period is about 28 days, and while the goose is sitting on the eggs, the gander keeps guard.īoth parents are involved in caring for the chicks. The nest is lined with feathers and down, and the goose lays an average of six eggs, each measuring about 6 x 9 cm. They build their nests on the ground in tall grass, reeds or on small floating islands of vegetation out on the water.
Greylag geese are monogamous and usually pair for life.