Adult Yellow-legged Gulls have bright yellow legs and a red beak spot

Young adults have a grey-streaked head and light yellow legs

Immature and non-breeding gulls have a black rather than red spot on the beak and very pale yellow legs

Younger still, but with plumage on the turn to adulthood, the yellow-legged gull has yellow-grey legs and a fully black beak

Very young yellow-legged gulls have pinky-grey legs, a fully black beak and speckled grey-brown plumage

The black-barred tail

Lesser Black-backed gull

Herring gull

Black-headed gull