Date: 3/8/17 10:03 am From: Harry LeGrand (via carolinabirds Mailing List) <carolinabirds...> Subject: Mountain waterfowl information -- Trumpeter Swan and Greater Scaup
Here is an e-mail that Steve Dinsmore, an excellent Iowa birder who spent some time birding in NC about 20 years ago, sent to Derb Carter about the Buncombe County swan.
I hope this email finds you doing well. I regularly peruse the Carolina Birding listserv and have been following the discussion of this swan. Both Tundra and Trumpeter swans are regular in Iowa (the latter are now more common) and this is a frequent i.d. challenge we experience. From that experience, I will say that the Buncombe Co. swan is absolutely a Trumpeter Swan (probably a subadult). The Jay Wherley photos from 24 Feb are conclusive and show the pink tomium, shape of feathering on the forehead, massive bill, head shape, etc. very clearly. One objective feature that can be easily measured on these photos is the comparison of distances between the eye and (1) the tip of the bill, and (2) the rear of the head. On this bird, the ratio of #1 to #2 is >1.5 whereas on Tundra Swan it would be <<1.5. A nice bird for western NC.
I suspect this conversation will happen more frequently in the upcoming years as Trumpeter Swans continue to increase. They were downright common in parts of Iowa this winter with a couple of locales each hosting >300 birds all winter!
"For what it's worth, since 1995, we have had over 30 sightings of Greater Scaup in the mountains of WNC! Many consisted of multiple birds."
So, I was mistaken in that there were barely 10 mountain records. This is in regard to the photo of the Greater Scaup on the CBC Photo Gallery. I will update the Birds of North Carolina species account accordingly for the scaup in the mountain region.