These two Lesser Black-backed Gulls (Larus fuscus ssp.) - a first-cycle and a second-cycle-type - were photographed as they flew upriver, crossing between Texas and Coahuila, Mexico, along Vega Verde Road near Del Rio, Val Verde county Texas on December 28, 2014:
Photo A followed by crops/zooms; 1C LBBG left bird of two at top/right; 2C-type LBBG leftmost bird:
Photo B followed by crops/zooms; 1C LBBG rightmost bird (note lack of paler inner primaries); 2C-type LBBG lower central bird:
Photo C (1C LBBG on right - note dark inner primaries):
Photo D followed by crop/zoom; 1C LBBG top-left:
