Lesser black-backed gull  (Larus fuscus)

The lesser black-backed gull is classified as Least Concern (LC) on the IUCN Red List (1).

A familiar and abundant inhabitant of the European coastline, the lesser black-backed gull (Larus fuscus) is a medium-sized gull species with a white head, white neck, dark grey back and black wings with white tips. The lesser black-backed gull can also be identified by its yellow legs and yellow bill, which is tipped with a red spot (2) (3).

The lesser black-backed gull is most similar in appearance to the great black-backed gull (Larus marinus), but is smaller and less powerful, and its back is less dark (4). Juveniles are also mistaken for immature herring gulls (Larus argentatus), but are darker and more contrastingly patterned (2).

Three subspecies of the lesser black-backed gull are currently recognised. These are primarily distinguished by slight variations in back colouration, as well as by range (4) (5).

The lesser black-backed gull breeds in Europe and Russia. Some populations are migratory and after the breeding season may travel to northern and western Africa, the Middle East or north-west India. One subspecies also migrates to the Caribbean and the eastern coast of the U.S. and Canada (2) (6).

An extremely versatile species, the lesser black-backed gull occupies a variety of coastal habitats, including estuaries, harbours and lagoons, as well as a number of inland artificial habitats, such as rubbish dumps and agricultural fields. Historically, the lesser black-backed gull only nested on moorland, on sandy, rocky and grassy coasts, or on rocky islands in rivers, lakes and seas. However, it has now also adapted to nest on the rooftops of buildings (2).

The lesser black-backed gull feeds on small fish, aquatic invertebrates, birds, birds’ eggs, carrion, offal, rodents and berries (2). Where other large gull species are present, it may vary its foraging strategy to specialise on certain types of prey. For example, it may increase the quantity of aquatic invertebrates and freshwater fish it eats, and may also plunge-dive to catch fish at deeper depths, a behaviour more commonly associated with seabirds other than gulls. The lesser black-backed gull also feeds on food scraps at rubbish dumps (2).

Lesser black-backed gulls are typically monogamous and arrive at nesting colonies from April. The nest can be anything from a heap of grass or feathers, to a simple, sparsely-lined scrape. Up to three eggs are laid, between May and mid-June, and are incubated by both adults for up to 28 days (2) (6) (7) (8). The chicks fledge at 30 to 40 days (2), after which they join other immature birds and non-breeding adults in ‘clubs’, spending most of their time resting and preening (4). The lesser black-backed gull becomes sexually mature at four years old (2).

As an extremely versatile and opportunistic species, the lesser black-backed gull has adapted well to human presence. By using buildings and other structures for nesting and by feeding on refuse, the lesser black-backed gull has expanded its range into urban environments, and its populations have rapidly increased. In fact, its numbers have increased to such a high level in many areas that it is now considered a pest species. In such areas, the lesser black-backed gull may predate upon and compete for food with rarer seabirds, meaning culls are needed to control its numbers and conserve other species (6).

However, in some parts of its range, such as in the United Kingdom, the lesser black-backed gull has recently been in decline. This is primarily due to increased competition for food with larger gulls, as well as changes in fishing practices that reduce the availability of discards, and the closure of landfill sites. The lesser black-backed gull may also be threatened by hunting in parts of Africa and Denmark, while human disturbance and egg collecting are other localised threats (6).

In the absence of any major threats to the lesser black-backed gull, it has not been the target of any known conservation measures. In fact, most plans directed at this species have concentrated on managing its population, to minimise its adverse effect on other seabirds. However, in light of its decreasing population in some areas, lesser black-backed gull numbers should be carefully monitored (6).

ARKive is supported by OTEP, a joint programme of funding from the UK FCO and DFID which provides support to address priority environmental issues in the Overseas Territories, and Defra

For more information on bird conservation:

• Royal Society for the Protection of Birds:
  http://www.rspb.org.uk/

 For more information on the lesser black-backed gull and other bird species:

• BirdLife International:
  http://www.birdlife.org/