Details
Larus marinus
The great black-backed gull is one of the largest gulls of the North Atlantic region. With a black mantle and heavy bill, it is a powerful coastal predator.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
It uses coasts, islands, estuaries, harbors, and waters of the North Atlantic, Arctic, Palearctic, and Nearctic regions. Breeding colonies occur on rocky islands, sandbars, and cliffs.
Length is 64-79 cm and weight 1-2.3 kg. Adults have a white head and underparts, black back and wings, a large yellow bill, and pale pink legs.
Diurnal and colonial at breeding sites, it may forage alone or with other gulls. Its size lets it dominate feeding areas and displace other seabirds.
A carnivore, it eats fish, crustaceans, eggs and chicks of seabirds, carrion, and scraps around fishing ports. It shifts readily between hunting and scavenging.
Nests are built on the ground from seaweed, grass, and debris. Both adults guard eggs and chicks and strongly defend the area around the nest.
It is listed as Least Concern. In coastal ecosystems it acts as a top opportunistic predator and responds quickly to human fishery waste.
