Great Black-backed Gull

What do Great Black-backed Gulls look like?

The Great Black-backed Gull is a large, eye-catching seabird with a black back and upper wings and pure white head, neck, tail, and underparts. They have pale pink legs and a bright yellow bill with a red spot toward the tip. Their piercing pale eyes are surrounded by a red eyelid.

In flight, white edges are visible around the upper side of the wings, as well as a large white spot at the tips. The underside of each wing is white, with darker flight feathers. The sexes have similar plumage, although females are smaller.

Juvenile Great Black-backed Gulls take about four years to attain their adult plumage. They are pale mottled brownish, with pale legs but dark bills and eyes. Their wings and backs are darker with a checkered appearance.

Apart from their larger size, these gulls appear similar to other Larus species like the Herring Gull (gray back) and Lesser Black-backed Gull (yellow legs).

How big are Great Black-backed Gulls?

The Great Black-backed Gull is a massive seabird and the largest gull species in the world. Males are typically larger in all respects.

Length

25 to 30 inches or 64 to 78 centimeters.

Weight

Most adults weigh 2.9 to 4.4 pounds or 1.3 to 2 kilograms. The largest males reach 5 pounds or 2.27 kilograms.

Wingspan

59 to 65 inches or 150 to 167 centimeters.

What sound does a Great Black-backed Gull make?

The Great Black-backed Gull produces similar calls to other large gulls but has a lower-pitched voice. They make a variety of sounds, including gruff, deep-voiced growls in flight, and a trumpeting ‘long call’ is made while raising and lowering their head.

What is the habitat of a Great Black-backed Gull?

Great Black-backed Gulls are usually found in coastal habitats like rocky shores, sandy beaches, and estuaries, although they also forage further out to sea. They live around larger inland water bodies in some areas and may scavenge on dry fields or around rubbish dumps for scraps.

What is the range of a Great Black-backed Gull?

Great Black-backed Gulls are restricted to the northern Atlantic Ocean, from the East coast of North America to Greenland, and from Svalbard south to Portugal. They may range far inland, particularly around the Great Lakes of the United States and Canada.

Where do Great Black-backed Gulls live?

Most Great Black-backed Gulls live near the seashore, although some birds travel inland and others forage further out to sea. They are accomplished swimmers, strong in flight, and comfortable on land.

How rare are Great Black-backed Gulls?

Great Black-backed Gulls are generally rarer and more solitary than other large gulls. Their numbers vary depending on the season and quality of habitat.

Where can you see Great Black-backed Gulls in the US?

Great Black-backed Gulls occur in coastal and continental shelf waters from Maine to Florida and rarely along the Gulf Coast to Texas. Look out for them throughout the year in the northeast but only in the winter south of North Carolina. They also visit the Great Lakes, traveling as far west as Lake Superior in winter.

Where can you see Great Black-backed Gulls in the UK?

Great Black-backed Gulls occur around the entire coastline of the United Kingdom. They also forage inland around dumps and reservoirs in the winter non-breeding season.

Where can you see Great Black-backed Gulls in Canada?

Great Black-backed Gulls occur along the eastern Canadian coastline from New Brunswick to Baffin Island. They also visit the Great Lakes in the winter, and some birds even breed around Lake Ontario and Lake Huron.

Do Great Black-backed Gulls migrate?

Great Black-backed Gulls are partial migrants. Some populations travel hundreds of miles to the south or inland after breeding, while others remain near their nesting grounds throughout the year.

• Look for the largest gull on the beach or at sea
• Observe its distinctive black back and wings against its white body
• Watch for aggressive behavior towards other birds
• In the UK and eastern North America, check coastal areas and large inland water bodies

What do Great Black-backed Gulls eat?

Great Black-backed Gulls have a varied diet that includes fish, crabs, mussels, and other marine organisms. They also eat small mammals, other birds and their eggs, carrion, and scraps. They find their food in the intertidal zone, at the surface of open water, and around seabird colonies.

What do Great Black-backed Gull chicks eat?

Great Black-backed Gull chicks eat fish and squid that both parents bring back to the nest. Younger chicks are fed directly from their parent’s bill, while older chicks eat meals regurgitated onto the floor.

Where do Great Black-backed Gulls nest?

Great Black-backed Gulls nest on the ground in a shallow scrape lined with feathers, plant matter, trash, and other soft materials. They nest on rocky areas, sand dunes, salt marshes, and grassy ridges near the coast but always above the high water line.

When do Great Black-backed Gulls nest?

Great Black-backed Gulls nest in the spring and summer. Most pairs lay their eggs in April or May. Their eggs take 26 to 28 days to hatch, and the young birds begin to fly when they are about 45 days old. Juveniles rely on their parents for over two months before gaining independence.

What do Great Black-backed Gull eggs look like?

Great Black-backed Gulls lay blotched and speckled eggs with a buff or olive background color. Their eggs are large, measuring approximately 54 millimeters wide and 77 millimeters long.

Do Great Black-backed Gulls mate for life?

Great Black-backed Gulls form long-lasting partnerships. They often mate for life, but pairs may divorce after unsuccessful nesting attempts.

Are Great Black-backed Gulls aggressive?

Great Black-backed Gulls are highly aggressive, relying on their size and power to overcome large prey. They are also aggressive towards other gulls and their own species, particularly when raising their chicks. These birds fight by pecking and striking with their wings, sometimes injuring their opponent in the process.

Where do Great Black-backed Gulls sleep at night?

Great Black-backed Gulls sleep on the ground in open areas such as beaches and fields, sometimes in large groups. They may lie on their belly or stand on one leg while sleeping, either resting their head against their breast or tucking it under their wing.

How long do Great Black-backed Gulls live?

Great Black-backed Gulls are known to live up to 26 years.

What are the predators of Great Black-backed Gulls?

Adult Great Black-backed Gulls are formidable birds, and healthy adults have few potential predators other than large raptors like Bald Eagles and White-tailed Eagles. Their eggs and chicks are more vulnerable to other large Gulls, Ravens, Crows, Rats, and Raccoons.

Are Great Black-backed Gulls protected?

Great Black-backed Gulls are a protected species in the United Kingdom, the United States, and Canada.

Are Great Black-backed Gulls endangered?

Great Black-backed Gulls are not endangered. These powerful seabirds have a large distribution and are ranked as a ‘Least Concern’ species on the IUCN Red List.

While currently listed as Least Concern, Great Black-backed Gulls face threats from habitat loss, pollution, and climate change. Some populations have declined due to reduced food availability and human disturbance at nesting sites. Conservation efforts focus on protecting breeding colonies and managing coastal habitats.