swan wiki:
>For other uses, see Swan (disambiguation). Cygnus Coscoroba Swans are large water birds of the family Anatidae, which also includes geese and ducks. Swans are grouped with the closely related geese in the subfamily Anserinae.Swans usually mate for life, though "divorce" does sometimes occur, particularly following nesting failure or the death of a partner (this can be due to 'capsizing': overturned swans lack the ability to right themselves and therefore drown). The number of eggs in each clutch varies both within and among swan species, typically between 3â8 eggs.
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