Tim writes: Bewick’s Swans (Cygnus columbianus bewickii) were named in honour of the bird engraver Thomas Bewick, though we don’t even know if he ever clapped eyes on one. In Bewick’s day (1753-1828) the two yellow billed swans were classed as one single species; the Wild Swan, as distinct from the Tame Swan (or Mute Swan as we now know it). British ornithologists decided that there were two species of wild swan only after Bewick’s Death, but William Yarrell decided to name the new species in his honour in 1830. Unfortunately for Bewick, his swan was just a subspecies of the American Tundra Swan, that had already been described to science in 1815. The Tundra Swan is identical in size and shape to Bewick’s, but has a much reduced area of yellow on the bill.
Incidentally, Thomas Bewick had another bird named in his honour that he never clapped eyes on, although he was aware of it. His friend John James Audubon named the American Bewick’s Wren (Thryomanes bewickii) after Thomas as thanks for giving him some lessons in bird illustration.
Bewick’s Swans nest on tundra in Arctic Russia and migrate mainly to England and the Low Countries for the winter. They are smaller than Whooper Swans with a shorter neck and rounder head. But the most diagnostic feature is the bill pattern, which has a rounder (rather than V shaped) area of yellow on the black bill. They remain in family parties even on their wintering grounds, so this should be adult male and female plus two well-grown cygnets from last season. The youngsters have sullied plumage (not white) and are very difficult to separate from juvenile Whoopers. But the developing round pale area on the black bill can just about be seen on the lower juvenile. But that upper juvenile does look rather large and has a V shaped pale area on its bill so I think this is a juvenile Whooper tagging along with three Bewick’s. I photographed these on the Ouse Washes in Norfolk in early January 2018, which is a traditional wintering site.
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