Birds in Bulgaria

L 40-46 cm, WS 100-115 cm. Breeds colonially or singly along coasts, on islands, in marshes, along rivers or at inland lakes. Lined nest usually near water on ground, preferably somewhat elevated, on boulders, poles in harbours, occasionally low trees, roofs of buildings, etc.
IDENTIFICATION: Three age-groups (see p. 168). Somewhat larger than Black-headed Gull. Much larger Herring Gull (p. 174) is the only similar common species; when size difficult to judge, look for smaller, narrower bill, more rounded head, much daintier general shape and quicker actions, less heavy, more active flight with often deeper and more energetic wingbeats, and narrower wings; adult also often shows more obvious tertial-crescent and larger ‘mirrors’; 1st-year has plain (not barred) midwing-panel giving neater upperwing pattern, and broad black, clear-cut band on white tail; also more neatly patterned underwing than immature Herring. Standing adult summer also resembles Kittiwake, but legs long and pale (not short and black), forehead less steeply rounded, and primaries are white-tipped and more extensively black. -Adult: Head white (streaked grey in winter), bill and legs greenish-yellow (bill duller in winter, with thin dark band). - Juvenile: Greybrown head and breast, scaly brown upperparts. - 1st-winter: Head and body similar to adult winter, but retains juvenile wings and tail; bill greyish with clear-cut black tip. - 1st-summer: Like 1st-winter, but wings and tail often much faded, and bill-base yellowish or pinkish. - 2nd-year: Like adult, but more black on outer wing, lacks prominent white primary tips, has smaller ‘mirrors’, and legs and black-banded or black-tipped bill often bluish greengrey.
VOICE: All calls much higher-pitched than Herring Gull’s, including ‘laughing’ call, ‘ke ke ke kleeeh-a … kleeeh-a … kay-a kay-a kay-a kay-a ke ke’. Call a distinctive, thinly yelping ‘keea’, often repeated. Persistent ‘klee-u klee-u …’ when alarmed (often good hint of bird of prey in vicinity!).