This first-cycle gull was photographed March 28, 2007 in the Coastal Plain near Houston and Galveston, Texas; note the following features that are suggestive of Slaty-backed Gull:- mid-brown primary tips with pale fringes; very pale, rather marbled greater coverts; strong, somewhat hooked bill; bunched tertials; tail and primaries paler, browner than nearby Am. Herring Gulls; pale inner webs on all visible primaries; underside of outer wing silvery with small dark tips to each primary; tail almost all-dark with the limited paler marks on R6s being irregular, somewhat longitudinal patterning, instead of lateral barring; the less-worn outer median and greater wing coverts being extensively pale with a dark subterminal diamond or arrowhead-shaped mark. Compare this bird to These slaty-backed Gulls from Japan. :
