Lesser Crested Tern (Thalasseus bengalensis)

Lesser Crested Tern

[order] CHARADRIIFORMES | [family] Laridae | [latin] Thalasseus bengalensis | [UK] Lesser Crested Tern | [FR] Sterne voyageuse | [DE] Ruppell-Seeschwalbe | [ES] | [NL] Bengaalse Stern

Subspecies

Genus Species subspecies Breeding Range Breeding Range 2 Non Breeding Range
Thalasseus bengalensis AF, OR, AU widespread coasts
Thalasseus bengalensis bengalensis Red Sea and Indian Ocean to South Africa
Thalasseus bengalensis emigratus Libya and Persian Gulf w and ne Africa, w India
Thalasseus bengalensis torresii Australasia Philippines to Bismarck Arch.

Physical charateristics

The Elegant Tern is a fairly large, slim tern, with a long, orange, slightly drooping bill. It has narrow, angled wings, a deeply forked tail, and a shaggy crest. The adult in breeding plumage has a gray mantle, white breast and belly, and white face with a black, crested cap. The legs are black. The adult in non-breeding plumage is similar, but with a white forehead that darkens to streaky black, as if the cap has receded. Juveniles appear similar to non-breeding adults, but their legs are yellow.

wingspan min.: 89 cm wingspan max.: 94 cm
size min.: 43 cm size max.: 44 cm
incubation min.: 21 days incubation max.: 25 days
fledging min.: 0 days fledging max.: 25 days
broods: 1   eggs min.: 2  
      eggs max.: 3  

Range

Africa, Oriental Region, Australasia : widespread coasts

Habitat

The species inhabits tropical and subtropical sandy and coral coasts and estuaries, breeding on low-lying offshore islands, coral flats, sandbanks and flat sandy beaches, foraging in the surf and over offshore waters.

Reproduction

A strongly social bird, this tern nests in tight groups. Like many other terns, Elegant Tern nests consist of a shallow scrape on the ground. Their typical clutch size is one egg, buff to white marked with dark brown, which is probably incubated by both parents. After a period of at least three weeks, the single chick hatches and spends a few days in the nest before joining a creche?a group of young birds who are still fed by their own parents. Post-fledging parental care lasts up to six months, during which time the chicks learn foraging skills.

Feeding habits

Elegant Terns forage by hovering over shallow water and then plunging into the water after fish. This tern can transport a single fish at a time crosswise in its bill. Elegant Terns forage on a variety of different schooling fish, with northern anchovy (Engraulis mordax) being their most important prey item. Other prey species include sardines, silversides, gobies, mackerels, and rarely, crustaceans. When feeding in flocks, these gregarious terns call frequently.

Conservation

This species has a large range, with an estimated global Extent of Occurrence of 100,000-1,000,000 km2. It has a large global population estimated to be 180,000-210,000 individuals (Wetlands International 2002). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.
Lesser Crested Tern status Least Concern

Migration

Inadequately known owing to lack of ringing studies. Migratory in Mediterranean, with post-breeding movement to Morocco and Senegambia, but only partly migratory in most range. Middle East birds pass E coast of Africa to Natal. N Indian Ocean populations partly migratory. Vagrant inland.

Distribution map

Lesser Crested Tern distribution range map

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