Page 221 - Complete Birds of Britain and Europe (DK - RSPB)

SKUAS, GULLS,AND TERNS
Order Charadriiformes Family Sternidae Species Sterna nilotica
Gull-billed Tern

thin dark band
on outer wings white head with thick bill round black
black eye patch cap
stout
black
bill
pale ADULT ADULT
grey (SUMMER) pale grey
tail (WINTER)
back
pale grey bloom
on wing feathers
wears off to ADULT
reveal black (SUMMER)
IN FLIGHT
white
underside

ne of the more localized terns of Europe,
Othis is unlike the black-capped, pale grey
and white “sea terns” in structure and behaviour
but similar in general appearance. It is a bird of black legs
freshwater marshes and coastal lagoons although it does
migrate over the sea. In winter, in Africa, Gull-billed Terns feed over
the open plains with huge numbers of animals; in Europe, they also FLIGHT: direct flight easy, languid, slightly more
feed over fields where livestock disturb insects, which they snatch in gull-like than smaller terns.
the air like giant swallows.They require careful FLIGHT PATTERN
separation from Sandwich Terns outside their In flight, the Gull-billed Tern shows
usual range, but in reality are generally relatively long, tapered wings with dusky
easy to identify. Despite having a characteristically trailing edges towards sharp tips.
grey tail, they usually look very pale, especially
in winter.
VOICE Nasal, deep gur-wik, laughing notes and
rattling call.
NESTING Grass-lined small hollow on sand or
mud near water; 3 eggs; 1 brood, May–June.
FEEDING Takes most food while flying, dipping
to snatch insects from ground or in air; eats some
small birds, rodents, and frogs.
SIMILAR SPECIES OCCURRENCE
Breeds and feeds around lagoons,
SANDWICH TERN longer, slimmer red WHISKERED TERN rice paddies, marshes, wet fields,
see p.218 bill with pale tip on bill winter;
see p.225 and high grassland, mostly in S
spikier black greyer and E Europe, very locally in North
cap
Sea area. Generally only very rare
smaller and migrant outside S Europe, usually
darker
red legs on or near coast.
COMMON TERN Seen in the UK
see p.220 JF M A M J JA S ON D
Length 35–42cm (14–16 1 ⁄2in) Wingspan 76–86cm (30–34in) Weight 200–250g (7–9oz)
Social Flocks Lifespan Up to 10 years Status Endangered†
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