Waterfowl have worldwide distribution and contain flightless species as well as others capable of long migrations. Some species, eg, northern pintail (Anas acuta), have very wide distribution; others are restricted to a few ponds on remote islands. Three species of swans, 5 of geese and 29 of ducks breed in Canada.
Waterfowl range in size from pygmy geese (Nettapus ssp.), averaging 300 g when fully grown, to North American trumpeter swans (Cygnus buccinator), exceeding 13 kg and having a wingspread of 250 cm.
In late summer as many as 80-100 million waterfowl are found in North America. Unfortunately, one duck species native to eastern Canada, the Labrador duck (Camptorhynchus labradorius), is now extinct.