Larus canus - Common Gull
Feather characters. Barbules are from short until medium length (0.7-1.3 mm). Barbules are divided into pigmented nodes and partly pigmented (less than 50%) internodes. Concentration of pigment varies in different body feathers. Both vase-shaped and slightly thickened nodes are located on proximal end of barbules (10-20 per mm). Most basal nodes are vase-shaped. Going distally, nodes abruptly decrease in size into slightly thickened nodes. On distal end, nodal structures are too small to qualify as nodes. Villi are absent and internodes are straight. Minute prongs may be present along the entire length of barbules, on both sides of the pennulum. These prongs are unequally distributed, and many nodal structures without prongs may be found.
Field characters. Size 41 cm. Weight: male 432 g (340-552), female 375 g (290-530) (Dunning, 1993). A medium-sized gull with medium grey mantle, back, and upperwing; wing-tips black with white spots; all other parts white. Can be distinguished from adult Herring Gull by much smaller size, slighter greenish-yellow bill (which lacks red spot), greenish-yellow legs, darker plumage and wings, latter protruding further beyond tail when folded. Non-breeding adults similar, but with grey streaks on crown, hindneck and sides of neck, greyish wash on lower hindneck, and some dusky edgings on breast. Juvenile is decidedly greyer in appearance than juvenile of Herring or Black-backed Gull; upperparts basically grey-brown, with white streaks on crown and face, grey-buff mottling on back, buff-white feather margins on wing-coverts; primaries brownish black; rest of plumage dull white, with some grey-brownish mottling on sides of neck, chest, and belly; tail with broad black terminal band. In flight, juvenile easily recognised by dark brown wing-bar on secondaries, blackish wing-tips and broad terminal black tail-bar, strongly contrasting with white tail.
Voice. Shriller and more mewing than that of other large gulls; commonest call is a shrill "keee-ya".
Distribution. A common partial migrant for northern half of Europe; very common in Scandinavia. Map: see MapIt.
Habitat. Reasonably tolerant of climatic variation, although avoiding extremes; in contrast to most congeners, equally well adapted to inland and coastal situations, but mostly in vicinity of water.
Food. Choice of food is varied, and dependant on habitat: inland terrestrial and aquatic invertebrates such as ants, earthworms, and insects as well as plant seeds; on the coast, takes molluscs, crustaceans, dead fish and seaweed. Will also kill small mammals and birds; occasionally takes birds' eggs.