Newsletter / Blog
2012-07-15 Rare bird sighting – Suffolk, UK.
Caspian
Tern is a July
rarity in the UK.
Caspian Tern
The Caspian
Tern - Hydroprogne caspia –is the world's largest tern. North American birds migrate to southern
coasts, the West Indies and northernmost South America.
African and Australasian birds are resident or disperse over short distances. European
and Asian birds spend the non-breeding season in the Old
World tropics.
Description
It is the world's
largest tern. Adult birds have black legs, and a long thick red-orange bill
with a small black tip. They have a white head with a black cap and white neck,
belly and tail. The upper wings and back are pale grey. The underwings are pale
with dark primary feathers. In flight, the tail is less forked than other terns
and wing tips black on the underside. In winter, the black cap is still present,
unlike many other terns, but with some white streaking on the forehead.
Call
Call a raspy
"kowk." Juvenile begging call a high pitched whistling; heard
frequently during migration and in winter.
Food
They feed mainly
on fish, which they dive for. They also occasionally eat large insects, the
young and eggs of other birds and rodents.
Breeding
Breeding is in
spring and summer, with one to three pale blue green eggs, with heavy brown
spotting, being laid. They nest either together in colonies, or singly in mixed
colonies of other tern and gull species. The nest is on the ground among gravel
and sand, or sometimes on vegetation. Incubation lasts for between 26 to 28
days. Fledging occurs after 35 to 45 days.
Conservation
Status – Least concern
This species has
an extremely large range. The population trend appears to be increasing, and
hence the species does not approach the thresholds for Vulnerable under the
population trend criterion. The species is currently threatened by the loss and
deterioration of breeding habitat through accelerated vegetation succession.
Birdwatching
Ask Aves Birding Tours/Safaris/Adventures
to create a tour for you or book on one of the following Aves Birding Tour/Safaris/Adventures see these striking birds: -
Aves Arid Birding
Tour/Safari/Adventure.
Aves Eastern Cape Birding
Tour / Safari /Adventure.
Aves KZN Birding
Tour / Safari / Adventure.
Aves Western Cape Birding
Tour / Safari / Adventure.
Aves West Coast
Birding Tour / Safari / Adventure. |