Mediterranean seagull

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Mediterranean seagull
Adult Mediterranean gull (Larus michahellis) in breeding plumage

Adult Mediterranean gull ( Larus michahellis ) in breeding plumage

Systematics
Class : Birds (aves)
Order : Plover-like (Charadriiformes)
Family : Laridae
Subfamily : Seagulls (larinae)
Genre : Larus
Type : Mediterranean seagull
Scientific name
Larus michahellis
Naumann , 1840
Youth dress
Bird in the first winter
L. m lusitanicus in the second winter. The extensive, dark dotted lines on the head and chest are typical of West Iberian birds
Bird between second and third winter
L. m. atlantis , at the end of January on Fuerteventura. In terms of the color of the upper side, the Atlantic populations are more like pale herring gulls. But they already blossomed into breeding plumage in December.
Mediterranean seagull in flight with a clearly visible hand swing pattern

The Mittelmeermöwe ( Larus michahellis ) is a bird art within the gulls (Larinae). It breeds in Macaronesia , the Bay of Biscay , the Iberian Peninsula , the Mediterranean - and the Black Sea region . There are also scattered occurrences in northern Western and Central Europe. The yellow-legged great gull was long regarded as a subspecies of the herring gull , later as a subspecies of the " white-headed gull ", which then turned out to be a paraphyletic taxon and was divided into Mediterranean and steppe gull .

description

At 52–58 cm and a wingspan of 120–140 cm, the Mediterranean gull is smaller than the very similar herring gull . The species is built more compactly overall and shows a stronger, front somewhat blunt, more rounded bill. The head appears larger, more arched in front and flatter at the top. The abdomen is overall slimmer, the wing tips extend 5–7 cm beyond the tail of the sitting bird. The legs are relatively long, so the bird looks taller. Young Mediterranean seagulls switch to adult dress when they are four years old . There is no sexual dimorphism .

Adult birds

In adult birds in breeding plumage, the head is pure white, as is the neck, nape, the entire underside and the tail. The yellow beak shows an extensive gony spot , which partly extends to the upper beak. The iris is lemon yellow, the eye is surrounded by a red ring. The legs are bright yellow. The top is light gray and slightly darker than that of adult herring gulls. The slightly bluish tint is missing as in the latter type. The upper side of the wing is also light gray except for a narrow white front and wide white rear edge as well as a predominantly black area on the tip of the hand wing. The black pattern of the hand wings is much more extensive than that of herring and steppe gulls. The six outer wrist wings have wide black subterminal ribbons that narrow towards the wrist and white tips. The black portion is very extensive on the outermost wrist and also shows a white field in the distal third. On the sixth hand swing from the outside, the subterminal black band is then only very narrow and is missing on the following inner ones. The under wing coverts are white.

Adult birds in winter plumage have fine, brown stripes on their crowns and ear covers, but these are usually concentrated around a not too extensive region around the eye. Some individuals show some black on the upper beak at the level of the gony's spot. The legs are less brightly colored than in summer.

Youth dress

Head of a Mediterranean seagull on in Rome

Young birds are generally gray-brown with a whitish head and a dark eye region. The feathers on the upper side are dark brown with light hems, so that the back, the shoulders and, when in flight, the upper side of the wing appear scaly. The wings are black-brown. The umbrella feathers have dark brown centers with oak leaf-like outlines in the distal part of the feather and wide, light hems. The rump and the base of the tail are white, only slightly interspersed with dark feathers and contrast with the black-brown end band. The chest and flanks are mottled gray-brown, but the belly and the central lower tail-coverts are whitish. The beak is black, the legs are flesh-colored, and the iris is dark.

Immature birds

Towards the first winter the back and shoulder feathers as well as some upper wing coverts are molten and are then gray-brown with a black-brown raised base, subterminal band and shaft line. The umbrella feathers are dark brown with relatively narrow, light hems.

Birds in the second winter already show parts of the light gray adult plumage on the upper side. This applies above all to the back, which can still be partially interspersed with brownish feathers, the upper wing covers, parts of which can still come from the first winter dress, and the umbrella feathers, of which usually not all are replaced. The wings are blacker and begin to express white tips. The dark eye mask is still there. The tip of the beak begins to lighten. The degree of progress of moulting into adult dress can vary greatly from person to person.

Birds in their third winter already resemble adult birds in winter plumage. However, they often show even more brown dots on the head, which can reach into the neck. The white tips of the hand wings are not so pronounced and the umbrella feathers still show dark areas. There is still a lot of black on the beak in the area of ​​the gony spot. The iris has already lightened.

voice

The Mediterranean gull has about the same call repertoire as the herring gull, but sounds deeper and sometimes weaker and more guttural. The main call, a waouw or graou, is similar to the corresponding call of the black-backed gull , albeit deeper. The cheering is faster, deeper and more guttural than with the herring gull and contains more individual elements. It reminds of a corresponding call of the black-headed gull . The "cat call" is harder, the "snap call" deeper and the "staccato call" faster and softer.

distribution

The breeding distribution of the Mediterranean seagull extends eastward from Macaronesia , the coasts of the Iberian Peninsula and the Biscay coast . It covers large parts of the Mediterranean coasts to the Adriatic Sea and south to Tunisia , the Pelagic Islands and Malta , the Aegean Sea , Crete and Cyprus and extends along the Dardanelles , the Marmara Sea and the Bosphorus to the Black Sea , where the species is in the western part and there occurs up the Danube as well as on the southeast coast. There are smaller breeding occurrences in Mauritania , Libya , Israel and Egypt . There are also scattered colonies or single broods in northern Western and Central Europe, for example in Switzerland, southern Germany, Austria, Poland, Slovakia, the Netherlands and Great Britain.

hikes

The Mediterranean gull is a resident or line bird that can be found in large parts of Europe outside of the breeding season. Roaming birds then probably try to find cheap feeding places and at the same time avoid competition with other species of great gulls. According to studies of north-west Spanish populations, one fifth of the young birds roam widely, the rest remain near the breeding sites or move inland. After the breeding season, adult birds seek out favorable moulting sites such as the Ebro Delta and later hibernate near the breeding sites.

Duration

The populations of the nominate form and north-west Iberia are estimated at 150,000–200,000 breeding pairs, and more than 8,000 other breeding pairs are believed to be found on the islands of the eastern Atlantic. The species is regarded by the IUCN as not endangered (“least concern”).

Geographic variation

Between two and three subspecies are recognized. The nominate form varies gradually (clinically) from east to west to larger and darker birds on top. The smaller subspecies of Macaronesia L. m. Atlantis shows a very dark upper side, especially in the Azores, which is reminiscent of the black-backed gull. Birds from Madeira or the Canaries are sometimes more similar to the nominate form. In the winter plumage, the head of adult birds is broadly dashed in brown. The controversial subspecies L. m mediates between nominate form and atlantis . lusitanius of the northwestern Iberian Peninsula in terms of both plumage color, size and DNA findings.

Larus michahellis atlantis

habitat

The Mediterranean seagull breeds mainly on rocky coasts or offshore rock and sand islands, but mud islands or high vegetation on lagoons , salines and estuaries or dunes are also accepted. Regionally, the species breeds on roofs within coastal villages, cities and port areas, such as in Istanbul and Bulgaria . Inland, gravel banks are mostly populated by inland waters.

Outside the breeding season, the Mediterranean seagull is mainly found in coastal areas where it forages in the open sea or in fishing ports or on beaches. Further inland, which the species primarily roams along rivers, it can also be found on agricultural land, on bodies of water and in other landscapes. Landfills are of particular importance.

food

The food spectrum is about as diverse as that of the herring gull. However, since dry silt and bank areas are rare in the distribution area of ​​the Mediterranean seagull at low tide, mussels and crustaceans recede as food components, while fish and cuttlefish make up a larger proportion. In addition, land animals from snails to small mammals or cultivated fruits such as cereals, olives, figs or the like are of greater importance.

supporting documents

literature

Web links

Commons : Mediterranean Seagull  - Collection of images, videos and audio files

Single receipts

  1. ↑ Main call: audio sample
  2. ↑ Glutz v. Blotzheim, p. 601, p. literature
  3. ↑ KM Olsen / H. Larsson, pp. 287f, s. literature
  4. ↑ A. Galarza, J. Hidalgo, G. Ocio, P. Rodríguez: Sexual size dimorphism and determination of sex in Atlantic Yellow-Legged Gulls Larus michahellis lusitanius from Northern Spain , Ardeola 55 (1), 2008, pp. 41-47
  5. ↑ Pierre Yesou: Les du complexe goélands Larus argentatus-cachinnans-fuscus: ou en est la systématique? , Ornithos 10, 2003, pp. 144-181
  6. ↑ KM Olsen / H. Larsson, p. 287, s. literature