It was very fortuitous that Bird A came in right as I am mired in writing the duck section of the Beached Bird Field Guide! Otherwise, I don’t think I would have had a chance at this i.d. What caught my eye on this wing were the pale primaries and secondaries contrasting with a darker forewing. This first brought to mind a scaup (and blog reader “Captain Eagle Eyes” also thought so. But scaup have a dark band at the tips of the secondaries, creating a border around the lighter speculum. Bird A’s secondaries are mostly pale gray, but actually have a band of almost white at their tips. There is also a hint of black and white barring evident up toward the shoulder which suggested male Redhead to me. Check out the wing of a Redhead here, at the Slater Museum’s website.
Friend of the SEANET blog Wouter concurs with the Redhead i.d., which makes me feel even better.
Bird B was universally recognized as a subadult gull. The slate gray mantle is much too dark for a Herring Gull, but is consistent with a Great Black-backed Gull. As Wouter pointed out, the dark on the mantle contrasting with the brownish wings suggests that this bird is between its 1st and 2nd years. I find it interesting that the characteristic checkered black and white pattern seen in younger birds of the species gets so muted and muddy by this age, looking more like the smeary brown wing of a young Herring Gull. Gulls are so gloriously confusing to me. But a Seanetter always welcomes a challenge, no?