The black-tailed gull (Larus crassirostris) is a gull native to shorelines of East Asia.
The black-tailed gull is medium-sized (46 cm) (19 Inches), with a wingspan of 126–128 cm (49.6 - 50.3 Inches). It has yellow legs and a red and black spot at the end of the bill. Males and females have identical plumage and features, although males are larger in size than females. This gull takes four years to reach full adult plumage. As the name suggests, it has a black tail. The bird has a cat-like call, giving it its Japanese name — umineko (海猫, "sea cat"), and Korean name — gwaeng-yi gull, which means "cat" gull. In Hachinohe they are one of the 100 Soundscapes of Japan.