Best time to see: Oct to mid Apr

Key facts

Large "grey goose" common throughout the country, ancestor of the farmyard goose

Feral birds were reintroduced into Essex from the 1970s on to establish the current breeding population

Breeds on large lakes and reservoirs, usually on small islands; immigrants from the north arrive in winter

Recognition

Largest "grey goose" with dark brown upperparts, orange bill and pink legs; 75–85 cm

Swims on the surface water, walks on and grazes grassland, feeding on grass, grain and roots

Strong flight showing pale forewing

Lifecycle

Pairs mate for life and renew their bond every year in an elaborate 'triumph ceremony'

Nest is a scrape near water; one brood of 4-6 white eggs, April–May

Female incubates, with the male on guard nearby; both parents tend the goslings, which fly after about 8 weeks