Tweets,
As I was just banding this summer in Fairbanks, AK and felt it good to jump in here as I saw and banded several individuals of all three species (Hermit, Swainson's and Gray-cheeked). The two biggest things to stick out for Gray-cheeked Thrush are the facial pattern to me, it lacks the distinct eye ring of swainson's, yet if looked at closely does have a very faint one, but this is seen in hand and by a birder might appear not to have one. Also the very gray appearance of the front facial area (eye to bill) is a VERY good indication to me. I did not notice obvious size differences among the swainson's or gray-cheeked I banded. I'm at the office right now, so can't check pyle for weights, but in my memory there wasn't a significant difference.

Scott Downes
downess at cwu.edu
Ellensburg WA