Great Black-Backed Gull Vs Lesser Black-Backed Gull: Key Differences Explained
The British coastline hosts two remarkable members of the Laridae family: the Great Black-Backed Gull (Larus marinus) and the Lesser Black-Backed Gull (Larus fuscus). These impressive seabirds, while similar in appearance, have distinct characteristics that set them apart.
Did you know that the Great Black-Backed Gull is the largest gull species in the world? Or that the United Kingdom is home to an astounding 40% of Europe’s Lesser Black-Backed Gull population? These fascinating birds play crucial roles in their coastal ecosystems, each occupying their own unique niche.
In this article, we’ll have a closer look into the key differences between these two remarkable gull species, from their physical characteristics to their behaviours and habitats!
Table of Contents
Key Takeaways
- Great Black-Backed Gulls are significantly larger, with a wingspan of up to 165 cm compared to the Lesser Black-Backed Gull’s 150 cm
- The Great Black-Backed Gull has pink legs, while the Lesser Black-Backed Gull has yellow legs
- Great Black-Backed Gulls are more dominant predators, capable of taking larger prey
- Lesser Black-Backed Gulls are more adaptable to urban environments and often nest on rooftops
- Both species are resident in the UK but have different migration patterns
- Great Black-Backed Gulls have darker black plumage compared to the Lesser Black-Backed Gull’s slate-gray back
- The Great Black-Backed Gull has a deeper, more resonant call than its smaller cousin
- Both species typically lay 2-3 eggs per clutch
What Is The Difference Between A Great Black-Backed Gull And A Lesser Black-Backed Gull?
While both gulls share similar colouring patterns, they differ significantly in size, behaviour, and habitat preferences. Let’s examine these differences in detail.
Visual Differences
The most obvious visual distinction between these gulls lies in their size and subtle colouring differences.
Great Black-Backed Gulls have a darker, more intense black on their backs and wings, contrasting sharply with their white plumage. Their legs are pink, and they possess a larger, more powerful yellow bill with a prominent red spot.
Lesser Black-Backed Gulls, in comparison, have a slate-gray to black upper side that’s typically lighter than their larger cousin. Their legs are distinctively yellow, and while they also have a yellow bill with a red spot, it’s proportionally smaller and less robust.
Both species display white heads, necks, and underparts, but the Great Black-Backed Gull’s larger size makes these features more prominent.
Differences In Habitat
While both species can be found along the UK coastline, they show different habitat preferences.
Great Black-Backed Gulls are primarily coastal birds, favouring rocky shores and islands. They’re less likely to venture inland except for visits to large bodies of water or landfill sites.
Lesser Black-Backed Gulls show more adaptability in their habitat selection. While they’re common along the coast, they’ve successfully adapted to urban environments, often nesting on building rooftops in cities. They’re more frequently seen inland and have become familiar birds in urban areas across the UK.
Nests & Eggs
Both species construct similar ground nests, but their nesting locations and egg characteristics differ.
Great Black-Backed Gulls typically nest on coastal cliffs, islands, or isolated areas, creating substantial nests from vegetation and debris. Their eggs are olive-brown to buff coloured with dark spots.
Lesser Black-Backed Gulls show more flexibility in their nesting choices, readily adapting to urban environments. They lay olive-brown or blue-green eggs with dark brown markings.
Both species typically lay 2 to 3 eggs per clutch, but Lesser Black-Backed Gulls are more successful in urban nesting situations.
Bird Calls
The vocal differences between these gulls are quite distinctive.
Great Black-Backed Gulls produce a deep, resonant “laughing” cry that’s noticeably lower in pitch than other gull species. Their calls are particularly commanding during the breeding season, reflecting their dominant status.
Lesser Black-Backed Gulls have a higher-pitched call that’s similar to other large gulls but distinct from their larger relatives. Their calls are typically more frequent but less imposing than those of the Great Black-Backed Gull.
Size & Weight
Size presents one of the most obvious differences between these species. Great Black-Backed Gulls are substantially larger, measuring 64 to 78 cm in length with a wingspan of 150 to 165 cm and weighing 1 to 2 kg.
Lesser Black-Backed Gulls are notably smaller, measuring 52 to 64 cm in length with a wingspan of 135 to 150 cm and weighing 620 to 1,000 g. This size difference makes them easily distinguishable when seen together.
SEE ALSO: Great Black-Backed Gull Life Cycle: Nest Building To Fledging (and everything in between)
Frequently Asked Questions
Lesser Black-Backed Gulls are more common in UK cities, having adapted well to urban environments. They frequently nest on buildings and are more tolerant of human presence than Great Black-Backed Gulls.
Yes, both species can be seen in the UK throughout the year. However, some Lesser Black-Backed Gulls migrate south during winter, while Great Black-Backed Gulls tend to be more resident, although they may move to different coastal areas seasonally.
Great Black-Backed Gulls are generally more aggressive and dominant due to their larger size. They are known to prey on smaller birds and can be quite territorial, especially during the breeding season.
