Page 214 - Complete Birds of Britain and Europe (DK - RSPB)

SKUAS, GULLS,AND TERNS
Order Charadriiformes Family Laridae Species Larus marinus
Great Black-backed Gull whitish head
black bill
large white patch
on outer wings broad wings faint markings IMMATURE
on white head (1ST WINTER)

dark flight
feathers
ADULT (SUMMER) pale
large yellow bill head
black back with red spot
ADULT
(WINTER)
IN FLIGHT

IMMATURE
chequered back
(2ND WINTER)
white
underside
white head
pale greyish,
ADULT whitish, or
(WINTER) pink legs

FLIGHT: strong but heavy, with slow, deep,
sweeping wingbeats. ADULT
(SUMMER)
his is the world’s largest gull,
Theavily built, big-billed, and fiercely
predatory.The size of the bill is a good guide to its identity even in
immature plumages. It is generally less abundant than the Herring
Gull, although it does form flocks of hundreds in areas where it is
common, even in summer when such gatherings follow trawlers
off northern Scotland. In winter, it usually forms only a small
proportion of the gull flocks on reservoirs inland but is widespread
on many coasts.
VOICE Deep, barking notes, hoarse yowk, gruff ow-ow-ow.
NESTING Shallow grass- or weed-lined scrape on cliff ledge or
pinnacle; 3 eggs; 1 brood; May–June. POWERFUL PRESENCE
FEEDING Bold and predatory in summer, eating seabirds and voles; Very big and strongly contrasted in pattern, Great
eats fish, crustaceans, offal, and rubbish from sea, beaches, and tips. Black-backed Gulls always dominate other gulls.
SIMILAR SPECIES OCCURRENCE
Widespread in NW Europe, on
LESSER BLACK- HERRING GULL immature, rocky coasts, breeding sparsely on
BACKED GULL similar to immature; rock pinnacles and offshore stacks,
see p.211 see p.209
often in flocks around coastal
smaller
pools. In winter, on beaches,
harbours, tips, and reservoirs,
yellow legs smaller
less browner and bill increasingly inland in W Europe.
white on less boldly Seen in the UK
wingtips chequered J F M A M JJ A S O N D
Length 64–78cm (25–31in) Wingspan 1.5–1.7m (5–5 1 ⁄2ft) Weight 1–2.1kg (2 1 ⁄4 –4 3 ⁄4lb)
Social Flocks Lifespan 10–20 years Status Secure
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