I've seen numbers of ebird reports this fall/winter period listing either
Tundra Swan or Trumpeter Swan, but not both or undetermined to species.
While many of these reports probably are accurate, I suggest a bit of
caution in lumping all swans seen to one species. Ten years ago you could
consider counties east of the Cascades and along most of the Columbia River
in WA having Tundra Swan as the default species, and many of the NW counties
dominated by Trumpeter Swans. I've definitely seen a change over the last
ten years, and I'm still fooled by flocks at Ridgefield NWR where the River
S route was almost exclusively Tundra Swans while Carty Lake a mile north
almost always had many Trumpeters when I got here almost 11 years ago. With
Trumpeter Swans increasing now into NW Oregon and ebird filters not flagging
them in many areas, listening can really help. The call usually is an
easier separation than a bill that doesn't show obvious yellow, and
(thankfully) it doesn't require high frequency audibility.



Randy Hill

Ridgefield

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