Lesser Black-backed Gull - Larus fuscus

Lesser black-backed gull (Larus fuscus) are a large gull species, with adult breeding plumage consisting of a white body, slate grey wings, yellow legs and a 'heavy 'yellow beak with a red spot (fig. 1) (Svensson et al, 2020).

Lesser black-backed gulls will breed in a range of habitats both coastally and inland, from saltmarshes and cliffs to moorlands, lakes and rooftops.They typically nest in colonies, sometimes with other gull species such as herring gull (Larus argentatus), but will nest in single pairs also (Svensson et al, 2020; Harris et al, 2024).  Lesser black-backed gull diet is varied and opportunistic, with this species taking advantage of natural prey in their local area from fish, eggs, carrion, berries as well as human rubbish (e.g. fishery discards and refuse tips). Lesser black-backed gull usually live to around 15 years, breeding at 4 years (Harris et al, 2024).

Population & Distribution:
At least 36% of the global lesser black-backed gull breeding population is hosted by Britain and Ireland, alongside around 87% of the subspecies graellsii population. Approximately 15% of the Britain and Ireland population can be found in Scotland (fig. 2) (Burnell et al, 2023; Harris et al, 2024).

Lesser black-backed gull are a common summer visitor to the east coast and a passage migrant, although have been historically underrecorded in the region. They breed in very small numbers along the east coast, with some localities recording nests in single digits (fig. 3). Breeding has been recorded previously at coastal sites such as Boddam, St Fergus gas terminal, Sands of Forvie and Aberdeen rooftops.The species has been recorded at other locations along the coast including Loch of Strathbeg, Girdleness, Inverugie, Donmouth, River Dee/Duthie Park throughout the year (North East Scotland Bird Reports).

Conservation Status:
Lesser black-backed gull are an Amber listed species, particularly due to the important of the breeding population in the UK (Stanbury et al, 2024). During the latest seabird census Seabird Counts 2015-21 it was found that the lesser black-backed gull population in Scotland had declined by 48% since the previous census Seabird 2000 in 1998-2002 (Burnell et al, 2023).

Factors Impacting Lesser Black-backed Gull:
Highly Pathogenic Avian Influenza (HPAI) has impacted great black-backed gull populations significantly, with a 25% decline overall in the UK reported between 2015-21 pre-HPAI baseline figures and 2023, with a 58% decline found in Scotland specifically (Tremlett et al, 2024).

Hatching success of lesser black-backed gulls is dependent on a number of factors, but is influenced by vegetation cover in the nesting habitat (Ross-Smith et al, 2015). A change or loss of nesting habitat from vegetation succession, development, or other land management could be some explanation for increases in rooftop nesting in recent years, and may be detrimental to future breeding success .

Great black-backed gull have been deemed high risk for collisions with offshore wind turbines. This is particularly due to their typical flight altitude overlapping with turbine blade heights, combined other factors such as a moderate amount of nocturnal flight activity (Furness et al, 2013). However, some tracking data does show that despite this overlap, lesser black-backed gull may have the agility to avoid individual turbines within a wind farm (Thaxter et al, 2018).

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