What a wonderful, illuminating discussion we are having on Cobirds
David Tonnessen alludes in his recent posts in the difficulty in separating juvenile Cliff swallows from juvenile and perhaps adult Cave Swallow.
Tony's post, in part, concurs with that premise but suggest that phase of juvenile plumage may not be that prevalent?
In the Sibley Guide the notation adjacent to the depiction of the juvenile Cliff Swallow (Jun-Dec) "juveniles extremely variable…"
So what do we do about this dilemma in Colorado. Could we just say that any well documented record of a Cave Swallow before June would be more viable than any juvenile record of a Cave Swallow discovered after June which would to have to have an exceptional level of documentation. Would even photographic evidence be satisfactory or would it take just specimen evidence?
Bob Righter
Denver CO
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