Breeding birds: 140,000 pairs
Wintering birds: 740,000
Adult herring gulls in breeding plumage have pale grey upperwings and mantles with black-tipped wings. The underparts and tail are pure white.
Herring gulls’ heads are white with a large yellow bill and red spot on the lower mandible. Their eyes are pale yellow with an orange eye-ring and their legs and feet are pink.
In winter plumage herring gulls have dusky streaks on their heads and the bill is duller in colour. Both sexes look similar but the male is larger than the female.
Juvenile herring gulls are grey-brown with white spots with black tail feathers. They get adult plumage when they are around 4 years old.
Herring gulls breed in large colonies sometimes at the edge of another seabird colony. Both male and female build the nest which is a shallow depression in the ground lined with soft materials such as grass and feathers although they will also use discarded materials such as paper or plastic.
Herring gulls lay 2-3 smooth, pale-green eggs with brown spots. They are incubated for 28-30 days. Chicks are fed regurgitated food by both adults. They fledge at 40-45 days and are fully independent after a further 10 days.
Herring gulls eat marine animals such as fish, crabs, molluscs, worms and mussels. They will also scavenge on rubbish dumps inland feeding on rodents, insects, berries and other birds and their eggs.
Herring gulls can be seen all year round in seaside towns during breeding season. They are also found anywhere inland where there is a food source.
Unlike many flocking birds herring gulls, aren’t very sociable and keep physical contact with other individuals to a minimum.