Gulls are a large group of about 50 species with represenatatives all over the globe and occupy a great diversity of habitats: sea coasts, lakes, rivers, cities and even deserts. Most of them are generalists and are all good swimmers, flyers and walkers. Gulls belong to the Charadrii (Gulls, Waders and Alcids) and are closely related tot the Terns (Sternidae), Skimmers (Rhychopidae) and Skuas (Stercoraiidae). Molecular studies show that Alcids (Alcidae) are members of the same clade.The taxonomy of the Gulls has been in constant review in the past. Gulls Until recently the majority of the Gulls were lumped in the genus Larus and a few other well established genera such as Rissa, Pagophila, Rhodosthetia, Xema and Creagus. This order apears to be not satisfactory considering the differences between the species groups embraced by the large genus Larus.
Genus Rhodostethia comprise one species Ross’s Gull Hydrocoleus roseus, high Arctic of eastern Siberia, Canada and Greenland.
White-headed Gulls and the Band-tailed Gulls of the genus larus constitute the largest group of gulls.
Physical charateristics
These gulls have a medium grey coloured back and the adults have yellow legs and a red orbital ring. The bill is also yellow with a small red mark at the end. Juveniles have streaked grey-brown bodies with dark bills and pink legs.
Copyright remark: Most sounds derived from xeno-canto
wingspan min.:
120
cm
wingspan max.:
140
cm
size min.:
52
cm
size max.:
58
cm
incubation min.:
27
days
incubation max.:
31
days
fledging min.:
35
days
fledging max.:
31
days
broods:
1
eggs min.:
2
eggs max.:
3
Range
Eurasia : Central Eurasia to Northeast China
Habitat
The Yellow-legged Gull is found in a great variety of habitats, preferring quieter locations such as small islands and coastal cliffs where it spends the night and nests. During the day, these birds are commonly seen in large numbers in areas of human settlement.
Reproduction
Monogamous and colonial. Nest built by both sexes on ground or on cliff ledges; lined with debris, grasses, and feathers. Three eggs, buff or olive and marked with brown, black, or darker olive, incubated 28-30 days by both adults. Young stay in nest 35-45 days; one brood per year.
Feeding habits
Yellow-legged Gull: Usually found near ocean or shorelines, feeding on almost anything it can eat. May parasites on food from other seabirds.
Conservation
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern. Larus cachinnans is a widespread breeder in coastal areas of southern and eastern
Europe, which constitutes >50% of its global breeding range. Its European breeding
population is large (>310,000 pairs), and increased between 1970-1990. Although
there were declines in Croatia and Georgia during 1990-2000, populations across
the rest of its European range increased or were stable, and the species showed a
marked increase overall. Four races of the Yellow-legged Gull inhabit the Mediterranean and Black Sea regions, the Atlantic coasts of the Iberian Peninsula and south-western France, the Azores and Madeira. Inside the continent it is breeding in Switzerland and Austria. Most of the populations are sedentary, but many birds from the Mediterranean move outside the breeding season northwards to Central Europe and the coasts of the Channel and southern North Sea. The population of those races in the European Union is estimated at 140000 breeding pairs. They have strongly increased in recent decades
Migration
Fairly well documented by ringing recoveries; migratory, partially migratory, and sedentary. Nominate cachinnans adults mostly sedentary or locally dispersive around Black and Caspian Seas; others, and especially immatures, disperse to south of breeding range and south-east Mediterranean, some to northern Red Sea and Persian Gulf, and also wander with michahellis along river valleys (especially Danube) to western and central Europe, a few regularly as far as north-east Germany and Poland, where some possibly remain to breed. Race michahellis probably originally sedentary, but following expansion to north and west in 1970s considerable post-breeding dispersal, particularly of young birds, takes place in these directions, from Mediterranean along rivers such as Rh
