Yellow-legged Gull

Informazioni

The Yellow-legged Gull (Larus michahellis), often referred to as 'Gabbiano Reale' in Italian, is a large gull species native to the Mediterranean region and parts of Europe. It is a highly adaptable and opportunistic feeder, thriving in both natural coastal environments and increasingly in urbanized areas. Its robust build, distinctive yellow legs, and piercing yellow eyes are key identification features in adult plumage. Historically considered a subspecies of the Herring Gull (Larus argentatus) or Lesser Black-backed Gull (Larus fuscus), it is now widely recognized as a distinct species due to genetic, morphological, and behavioral differences.

Dimensioni e longevità

Lunghezza

52-60 cm

Apertura alare

120-140 cm

Peso

700-1500 g

Longevità

Up to 25-30 years in the wild

Dieta

Omnivore (highly opportunistic, including fish, crustaceans, mollusks, insects, small mammals, birds, eggs, carrion, refuse, and human food waste)

Caratteristiche fisiche

Piumaggio

Adult breeding plumage: White head, neck, underparts, and tail. Mantle and upperwings are medium grey. Primary wingtips are black with prominent white 'mirrors' (apical spots) on P9 and P10. Adult non-breeding plumage: Similar to breeding, but with fine streaking on the head and nape, particularly around the eye and hindneck. Juvenile plumage: Complex and highly variable, typically mottled brown and grey with dark streaking, dark bill, and dark eyes. Progresses through several immature plumages over 3-4 years.

Forma del becco

Strong, relatively heavy bill, yellow with a prominent red spot (gonys spot) on the lower mandible in adults. Juveniles have a dark bill, which gradually lightens and develops the red spot.

Colore degli occhi

Pale yellow with a red orbital ring in adults. Juveniles have dark brown eyes, which lighten with age.

Colore delle zampe

Bright yellow in adults, often duller or greenish-yellow in non-breeding season. Juveniles have pinkish-grey legs, gradually turning yellow.

Caratteristiche distintive

Bright yellow legs, yellow eye with red orbital ring, prominent red gonys spot on the bill, and a relatively dark grey mantle compared to Herring Gull. The black primary pattern with distinct white mirrors is also characteristic.

Aspetto giovanile

First-winter birds are heavily mottled brown and grey, with a dark bill, dark eyes, and pinkish-grey legs. The tail is dark with a narrow white base. The primaries are dark. Second-winter birds show a mix of juvenile and adult-like feathers, with a paler head, greyer mantle, and a developing yellow bill base. Third-winter birds are largely adult-like but may retain some dark markings on the primaries or tail, and the bill may not be fully yellow with a red spot.

Cambiamenti stagionali

Adults show only minor seasonal changes, primarily the development of fine streaking on the head and nape during the non-breeding season. The intensity of leg and orbital ring color may also vary slightly.

Dimorfismo sessuale

Males are generally slightly larger and heavier than females, but plumage is identical. Size difference is often not discernible in the field.

Come identificare

1. 1

   Leg Color

   Adults have bright yellow legs. This is a primary distinguishing feature from Herring Gulls (pink legs) and a shared feature with Lesser Black-backed Gulls (darker mantle).

2. 2

   Mantle Color

   Medium grey mantle, darker than Herring Gull but significantly paler than Lesser Black-backed Gull. Compare with local Herring Gulls for accurate assessment.

3. 3

   Eye and Orbital Ring

   Piercing pale yellow eye with a distinct red orbital ring in adults. This contrasts with the dark eye of juveniles and the less prominent orbital ring of some other large gulls.

4. 4

   Bill

   Strong yellow bill with a prominent red gonys spot on the lower mandible in adults. Juveniles have a dark bill that gradually lightens.

5. 5

   Primary Pattern

   Black primary wingtips with two prominent white 'mirrors' (apical spots) on the outermost two primaries (P9 and P10). The extent of black on the primaries is intermediate between Herring and Lesser Black-backed Gulls.

6. 6

   Voice

   Listen for the deeper, more resonant 'laughing' call, which is distinct from the higher-pitched calls of Herring Gulls.

7. 7

   Juvenile Plumage

   First-winter birds are heavily mottled brown and grey, with a dark bill, dark eyes, and pinkish-grey legs. The overall impression is 'dirtier' and more streaky than juvenile Herring Gulls, and less uniformly dark than juvenile Lesser Black-backed Gulls.

Habitat e areale

Biomi

Coastal areas, marine environments, estuaries, large rivers, lakes, urban areas, agricultural land, landfills.

Areale geografico

Primarily the Mediterranean Basin, extending northwards along the Atlantic coasts of Europe (France, Portugal, Spain) and into Central Europe along major rivers. Also found in parts of the Black Sea and occasionally further east. Expanding its range northwards.

Fascia altitudinale

Sea level to low-lying inland areas, occasionally found at higher altitudes when foraging.

Ambienti preferiti

Rocky coasts, islands, cliffs for nesting; sandy beaches, estuaries, harbors, fishing ports, urban centers, landfills, and agricultural fields for foraging.

Comportamento

Periodo di attività

Diurnal, primarily active during daylight hours for foraging and social interactions.

Abitudini alimentari

Highly opportunistic and omnivorous. Feeds on fish (often scavenged or stolen), crustaceans, mollusks, insects, small mammals, eggs and chicks of other birds, carrion, and a significant amount of human refuse from landfills, fishing boats, and urban areas. They are adept at scavenging and kleptoparasitism (stealing food from other birds).

Comportamento sociale

Highly social, especially outside the breeding season, forming large flocks at roosts, feeding sites (e.g., landfills), and during migration. Breeds in colonies, often mixed with other gull species.

Tipo di volo

Strong, direct flight with powerful wingbeats. Also capable of soaring and gliding, especially when searching for food or during migration. Often seen circling over food sources or roosting sites.

Migrazione

Generally considered a partial migrant or resident. Northern populations and younger birds may undertake short-distance migrations, moving south or west from breeding grounds in winter. Mediterranean populations are largely resident, though some dispersal occurs. Increasingly, many populations are becoming more sedentary due to abundant food sources in urban environments.

Territorialità

Territorial during the breeding season, defending a small area around the nest within the colony. Outside breeding, they are less territorial, focusing on communal feeding and roosting.

Riproduzione

Stagione riproduttiva

Typically from March to July, with peak egg-laying in April-May.

Abitudini di nidificazione

Nests colonially, often on rocky cliffs, islands, coastal islets, or increasingly on rooftops and other man-made structures in urban areas. The nest is a bulky scrape lined with vegetation, feathers, and debris.

Dimensione della covata

2-3 eggs, rarely 1 or 4.

Descrizione dell'uovo

Typically 2-3 eggs, olive-brown to greenish-blue, heavily spotted and blotched with dark brown or black. Average size is about 65 x 45 mm.

Periodo di incubazione

27-31 days, incubated by both parents.

Periodo di involo

35-40 days after hatching. Chicks are semi-precocial, leaving the nest shortly after hatching but remaining dependent on parents for food and protection.

Cure parentali

Both parents share incubation duties and care for the chicks, providing food and protection until they fledge and for some time thereafter.

Dove trovarlo

Consigli sul campo

1. Observe Leg Color. This is often the quickest and most reliable field mark for adults. Ensure good lighting to confirm the yellow hue.
2. Compare Mantle Shade. If other large gulls are present, compare the grey shade of the mantle. Yellow-legged Gulls are intermediate between Herring and Lesser Black-backed Gulls.
3. Study Primary Pattern. Pay attention to the black markings and white mirrors on the wingtips, especially when the bird is in flight or resting with wings folded.
4. Listen to Calls. Familiarize yourself with their distinctive deep 'laughing' call, which can help differentiate them from other large gulls even when visual cues are difficult.
5. Age Identification. Be aware of the complex immature plumages. Juveniles look very different from adults and require careful observation of bill, eye, and leg color progression.
6. Habitat Context. While adaptable, their primary range is the Mediterranean. Knowing the typical distribution can aid in initial identification.

Specie simili

Fatti rapidi

Primary Habitat:

Coastal and urban areas

Diet Type:

Omnivorous scavenger

Leg Color (Adult):

Bright yellow

Eye Color (Adult):

Pale yellow with red orbital ring

Conservation Status:

Least Concern

Nesting:

Colonial, on cliffs or rooftops

Curiosità

• The Yellow-legged Gull was only recognized as a full species relatively recently, having been considered a subspecies of Herring Gull or Lesser Black-backed Gull for many years.
• They are highly intelligent and adaptable, quickly learning to exploit new food sources, including human waste, which has contributed to their population growth and range expansion.
• In some urban areas, Yellow-legged Gulls have become a significant presence, often nesting on buildings and interacting closely with human populations.
• Their diet is incredibly varied, reflecting their opportunistic nature; they are known to prey on small birds and mammals, as well as scavenge almost anything edible.

Classificazione scientifica

Regno

Animalia

Phylum

Chordata

Classe

Aves

Ordine

Charadriiformes

Famiglia

Laridae

Genere

Larus

Specie

Larus michahellis

Esplora Yellow-legged Gull