It's not all that simple about geese! Besides the fact that the word goose has an irregular plural form geese, it's also a challenge to find a right word to name a group of these birds.

A collective noun, defining a group of geese, is usually chosen on the basis of the place of the group. If you see several geese walking in a group on land, you are to call them a gaggle; but when you see a group of geese flying, you can call them a skein.

Geese are waterfowl belonging to the tribe Anserini of the family Anatidae. This tribe comprises the genera Anser (the grey geese), Branta (the black geese) and Chen (the white geese). A number of other birds, mostly related to the shelducks, have "goose" as part of their names. More distantly related members of the family Anatidae are swans, most of which are larger than true geese, and ducks, which are smaller.

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