A bevy of trumpeter swans (Cygnus buccinator), captured in Idaho by reader Stephen Barnard (click to enlarge):
And somebody tell us what the dark birds are—juveniles?
The species is described in Wikipedia as “the heaviest bird native to North America and, on average, the largest extant waterfowl species on earth.” How big are they? (my emphasis):
Adults usually measure 138–165 cm (54–65 in) long, though large males can range up to 180 cm (71 in) or more. The weight of adult birds is typically 7–13.6 kg (15–30 lb), with an average weight in males of 11.9 kg (26 lb) and 9.4 kg (21 lb) in females.The wingspan ranges from 185 to 250 cm (73 to 98 in), with the individual wing chords measuring 60–68 cm (24–27 in). The largest known male Trumpeter attained a length of 183 cm (72 in), a wingspan of 3.1 m (10 ft) and a weight of 17.2 kg (38 lb).