Dear ID Frontiers NYSBirds, I would appreciate feedback regarding an adult yellow-legged Larus found 22 Feb at Old Field Point, on the north shore of central Long Island, New York.
Broadly speaking, it is a Herring Gull type, but there are reasons to doubt each of the usual (and less usual) interpretations of Herring-like gulls with yellow legs in this region at this time of year. Most often, such birds prove to be otherwise typical smithsonianus Herring Herring Gulls, which regularly show some degree of yellow color in the legs and feet in late winter and early spring (as do small numbers of local Great Black-backed Gulls). Another frequent interpretation is Herring Gull x Lesser Black-backed Gull hybrid, which the original finder, Patrice Domeischel, considered in the present case because of the bird's slightly darker than smithsonianus mantle. A third possibility, always present in the minds of New York gull aficionados, is Yellow-legged Gull, which was considered by Patrice, and also by Peter Osswald, who independently found the bird on 23 Feb. Patricia Lindsay and I studied the bird yesterday afternoon (23 Feb), and I have reservations about all three of these hypotheses, which are explained in my eBird report (link below). Briefly, Yellow-legged Gull is counter-indicated by this bird's heavier than expected head and nape streaking; it's notably large (larger than typical smithsonianus) apical spots on the primaries; and other details of the wingtip pattern (more white, less black than typical for smithsonianus, let along Yellow-legged Gull). The latter two points regarding the primaries also point away from Lesser Black-backed Gull ancestry. Finally, American Herring Gull is problematic by virtue of the subtly (but clearly) darker than typical mantle tone; the completely clear yellow tones of the the legs and feet; and details of the wingtip pattern. I could not see the orbital ring color. Photos by Patrice and Barbara Lagois seem to show it is red, but are not decisive on this point, in my opinion. I wonder if this bird might represent a yellow-legged example of northern European L. a. argentatus, which I do not know well in life, but which is described as having a slightly darker mantle tone than smithsonianus, a wingtip pattern very similar to the present bird, and a relatively high incidence of yellow leg color. My preliminary analysis (with photos by Barbara Lagois) and two of Patrice's checklists, also with excellent photos can be found here: https://ebird.org/checklist/S103599677 https://ebird.org/atlasny/checklist/S103599196 https://ebird.org/atlasny/checklist/S103596988 Shai Mitra Bay Shore, New York -- NYSbirds-L List Info: http://www.NortheastBirding.com/NYSbirdsWELCOME.htm http://www.NortheastBirding.com/NYSbirdsRULES.htm http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L 3) http://birding.aba.org/maillist/NY01 Please submit your observations to eBird: http://ebird.org/content/ebird/ --
