Very rare, though adults increasingly reported. ID: 4-yr gull. Slate-gray upperparts, similar color tone to LBBG. Compared with LBBG it is bulkier, has long parallel-sided pale yellow bill, deep pink legs, and broad, white trailing edge to wings. The clincher is the ‘string of pearls’: white separating the gray from the black wing-tips of middle primaries. Young birds fairly uniform brown like THGU.