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Gull-billed Tern
(Gelochelidon nilotica)
: "Long-legged Tern"
 German name(s): "Lachseeschwalbe"
Size: 33-42 cm; wing span 75-90 cm
Weight: 150-290 g
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Similar species |
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Physical description |
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 Click here for a physical description
Gull-billed Terns are medium-sized terns. During the
breeding
breeding
season they have a black cap, white front
(throat, neck, chest, belly and vent) and grey wings.
The black eyes are surrounded by the black cap, while
the frons (base of the bill) is also black. The stout bill
is black, the short legs and feet are also black.
In eclipse
the cap becomes mostly white, with grey patches
remaining behind the eyes and some mottled black-and-white
remaining at the back of the head.
Juveniles
are mottled grey, with a mottled cap and black eye patches.
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Twitcher's tip |
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Compared to other, similar terns, the Gull-billed Tern has the most
massive black bill (hence its name).
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Taxonomy, classification |
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See Gull-billed
Tern at Wikipedia  .
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Range, habitat, finding this species |
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Click here for information on habitat
and range
The overall distribution of this species can be assessed based
on sighting reports submitted by birdwatchers to the
ebird.org
website.
The global distribution of the Gull-billed Tern is available
HERE
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Gull-billed Terns are a global species, of which there are 6 races.
All races are dispersive after the end of the breeding season, and
those breeding in the northern hemisphere are the most strongly
migratory races.
Nominate race "nilotica" have a very extended breeding range, from
Europe and North Africa in the West, through the Middle East and
southern-central Asia to western China and Thailand in the East.
The breeding range of the Asian race "affinis" extends from
parts of Indonesia (Borneo, Sulawesi, Sumatra) through the
Philippines and south-eastern Asia, South and East China up to
Japan in the East.
Race "macrotarsa" breeds
only in Australia.
The three other races, "aranea", "vanrossemi" and "gronvoldi"
are found in various parts of the Americas (for details see, e.g.,
Wikipedia).
The northern races tend to spend the winters farther South, e.g.
in southern America, in Africa, south-eastern Asia and even
New Zealand.
Gull-billed Terns, nominate race "nilotica",
are breeding migrants to Europe from the South.
Apart from a few suitable locations inland, such as major
rivers (e.g. Danube) or lakes (Lake Superior), they populate
mostly coastal regions. They are found during their migration
to the breeding grounds all around the Mediterranean
Sea, but also along the Iberian and French Atlantic coastline,
the coastlines of England and Wales, the North Sea coastline
up to southern Scandinavia and parts of the coastline of the
Baltic Sea.
Gull-billed Terns can be found above coastal waters, but also
in tidal flats and inland, in the shallows of freshwater lakes,
including ephemeral lakes and ephemeral wetlands.
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Sightings |
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Click here for sighting information
Race "nilotica"
We have not spotted Gull-billed Terns, nominate race
"nilotica" in Europe yet. The photos shown below were
taken in Egypt. All photographic information presented on
this page has kindly been contributed by M. Eaton.
Race "macrotarsa"
Race "affinis"
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Photos |
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Race "nilotica"
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ADULT |
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BREEDING |
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Gull-billed Terns in both breeding plumage (black caps) and
non-breeding plumage
(strong black bills, but white cap), on a roost together with
other seabirds, primarily a flock of Black-headed Gulls
(photo courtesy of M. Eaton)
[November 2017]
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NON-BREEDING |
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Lateral view of a Gull-billed Tern in non-breeding plumage (photo courtesy of M. Eaton)
[November 2017]
Race "affinis"
Gull-billed Terns, race "affinis", were
photographed by us in
Australia.
Race "macrotarsa"
Gull-billed Terns, race "macrotarsa", were
photographed by us in
Australia.
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Food, Diet |
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Like all terns, Gull-billed Terns feed on fish, which they catch
with their bills just under the surface of water in a steep
high-speed dive from considerable height.
These pages are largely based on our own observations and those of our
contributors. The structure of these bird pages is explained HERE. For more salient facts on any bird species
please refer to a field guide.
Distribution
Breeding
Nest
Eggs
Behaviour
Call/s
