The Lesser black-backed gull is smaller (hence the name) than the Great black-backed gull, but is still a fairly large gull, with a length of around 60 cm (24 in.). In the breeding adult the head and under parts are white, the back and wings are black. In the winter the head and neck are streaked with grey. Juveniles have a black bill, white under parts streaked with brown, and brown back and wings with the feathers white-lined in a scaly fashion. The legs are yellow.

The lesser black-backed gull is more closely related to the herring gull than the great black-backed gull in spite of its name, but can be confused with the latter. One way to distinguish the species is the size (smaller for the lesser black-backed gull), also the legs are yellow instead of pink for the great black-backed gull, and finally the yellow bill of the lesser black-backed gull is smaller relative to the head size (see photo below).

This gull has an omnivorous diet like other gull species, i.e. including carrion and garbage. Its habitat is along the coast mainly. This gull species does not breed on PEI, but rather is a rare visitor from Europe, where it breeds in colonies and is often seen with herring gulls.

Lesser black-backed gull - Brander's pond, PEI - May 2017 - by Marie Smith
Lesser black-backed gull – Brander’s pond, PEI – May 2017 – by Marie Smith