Yellow-legged Gull

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iYellow-legged Gull

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Laridae
Genus:	Larus
Species:	L. michahellis

Binomial name

Larus michahellis
Naumann, 1840

The Yellow-legged Gull (Larus michahellis) is a large gull of Europe, the Middle East and North Africa. It is sometimes considered to be part of the same species as Caspian Gull and the combined species is then called Larus cachinnans.

1 Classification
2 Distribution
3 Description
4 Diet
5 Reproduction
6 References
7 External links

[edit] Classification

The taxonomy of the Herring Gull/Lesser Black-backed Gull complex is very complicated. This group has a ring distribution around the northern hemisphere. Differences between adjacent forms in this ring are fairly small, but by the time the circuit is completed, the end members, Herring Gull and Lesser Black-backed Gull, are clearly different species. However, different authorities recognise up to eight species in this complex.

It is now generally accepted that the Yellow-legged Gull is a full species, but until recently there was much disagreement. For example, the BOU in Great Britain placed Yellow-legged Gull as a subspecies of the Herring Gull, while British Birds magazine split Yellow-legged Gull from Herring Gull but included Caspian Gull in the former. However, recent DNA research has shown that Caspian Gull is basal to the complex, and cannot be in the same grouping as the other form.

There are two subspecies of Yellow-legged Gull: michahellis (named for the German zoologist Karl Michahelles), which breeds in the Mediterranean, and atlantis, on the Atlantic islands. Birds breeding in Portugal and the Atlantic coast of Spain are sometimes considered to be a third subspecies: lusitanius.

[edit] Distribution

The breeding range is centred around the Mediterranean Sea. In North Africa it is common in Morocco, Algeria and Tunisia and increasing in plaecs. Recent breeding has occurred in Libya and Egypt. In the Middle East a few breed in Israel and Syria with larger numbers in Cyprus and Turkey. In Europe there are colonies all along the Mediterranean coast and it also breeds on the west side of the Black Sea. Here it overlaps with the Caspian Gull but there is a difference in habitat with the Yellow-legged Gull choosing sea cliffs. In recent decades birds have spread north into central Europe and first bred in Britain in 1995. The Yellow-legged Gull is also common in the Canary Islands, Madeira Islands and the Azores.

Many birds remain in the same area all year round but others migrate to spend the winter in mild areas of Western Europe or head south as far as Senegal, the Gambia and the Red Sea. It is reported as a vagrant to northeastern North America and Nigeria.

Adult Yellow-legged Gull, Portugal

[edit] Description

Adults are similar to Herring Gull but have yellow legs. They have a grey back, slightly darker than Herring Gull. They are much whiter-headed in autumn, and have more extensively black wing tips with few white spots. They have a red spot on the bill like Herring Gull. There is a red ring around the eye like the Lesser Black-backed Gull but unlike the Herring Gull which has a yellow ring.

First-year birds have a paler head, rump and underparts than Herring Gull. They have a dark bill, dark flight feathers and a well-defined black band on the tail.

The call is a loud laugh which is deeper and more nasal than the call of the Herring Gull.

[edit] Diet

These are omnivores like most Larus gulls, and they will scavenge on rubbish tips and elsewhere, as well as seeking suitable small prey in fields or on the coast, or robbing plovers or lapwings of their catches.

Young Yellow-legged Gull near Marseille.

[edit] Reproduction

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 they have started nesting on buildings. The eggs are incubated for 27-31 days and the young birds fledge after 35-40 days.

[edit] References

BirdLife International (2004). Larus cachinnans. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes justification for why this species is of least concern
"National Geographic" Field Guide to the Birds of North America ISBN 0-792-26877-6
Seabirds, an Identification Guide by Peter Harrison, ISBN 0-7470-8028-8
Handbook of the Birds of the World Vol 3, Josep del Hoyo editor, ISBN 84-87334-10-5
"National Audubon Society" The Sibley Guide to Birds, by David Allen Sibley, ISBN 0-679-45122-6
D.W. Snow & C.M. Perrins (1998) The Birds of the Western Palearctic, Concise Edition (Vol. 1), Oxford University Press, Oxford.
Alan Harris, Laurel Tucker & Keith Vinicombe (1994) The Macmillan Field Guide to Bird Identification, Macmillan Press.
Lars Svensson & Peter J. Grant (1999) Collins Bird Guide, HarperCollins, London.