The yellow-legged gull or western yellow-legged gull (Larus michahellis) is a large gull found in Europe, the Middle East and North Africa, which has only recently achieved wide recognition as a distinct species. It was formerly treated as a subspecies of either the Caspian gull L. cachinnans, or more broadly as a subspecies of the herring gull L. argentatus.

The genus name is from Latin Larus which appears to have referred to a gull or other large seabird, and the species name honours the German zoologist Karl Michahelles.

Classification

It is now generally accepted that the yellow-legged gull is a full species, but until recently there was much disagreement. For example, British Birds magazine split the yellow-legged gull from the herring gull in 1993 but included the Caspian gull in the former, They will scavenge on rubbish tips and elsewhere, as well as seeking suitable prey in fields or on the coast, or robbing smaller gulls and other seabirds of their catches. Although urban populations are generally opportunistic scavengers, they can shift to a predatory diet if necessary; this was observed during the lockdown of Italy in 2020, when the lack of food scraps led the yellow-legged gulls of Rome to take prey as large as rats and rock doves.

Atlantic gulls in Gibraltar have been observed and photographed picking and eating fruit from olive trees in flight. A study of a yellow-legged gull population breeding in the south-eastern part of the Bay of Biscay showed little overlap with fishing vessels, indicating that this population did not obtain most of its fish prey from interactions with offshore fishing activity but most possibly by taking fish remains in harbours and by feeding themselves.

Reproduction

thumb| Larus michahellis atlantis - [[MHNT.]]

thumb|Three yellow-legged gull eggs in a ground nest in the [[São Miguel Island|Azores.]]

thumb|A yellow-legged gull egg in a ground nest with a 2-euro coin for scale.

Yellow-legged gulls usually breed in colonies. Eggs, usually three, are laid from mid March to early May and are defended vigorously by this large gull. The nest is a sometimes sparse mound of vegetation built on the ground or on cliff ledges. In some places, such as Gibraltar, Galicia and Portugal, they have started nesting on buildings, inside cities and even on trees. The eggs are incubated for 27–31 days and the young birds fledge after 35–40 days.

References

  • Mediterranean Yellow-legged Gull - Larus michahellis, Svetla Dalakchieva