ニシズグロカモメ Ichthyaetus melanocephalus

Medium-sized gull, slightly larger than Black-headed Gull, more similar to Common Gull in size and shape but bill stouter. Adult is distinctive, the only small gull with snow-white wingtips; breeding plumage has black hood. Nonbreeding and immature have distinctive, dark smudges behind each ear. Juvenile has mottled brownish back, which molts to pale gray by winter. Breeds in typically water-adjacent colonies scattered throughout Europe and Western Asia, often with Black-headed Gulls. Frequently found with flocks of other medium-sized gulls outside of the breeding season.