Thalasseus
Encyclopedia
Thalasseus, the crested terns, is a genus of six species of seabird
s in the tern
family. Thalasseus signifies a "creature of the sea". It has a worldwide distribution, and many of its species are abundant and well-known birds in their ranges. This genus had originally been created by Friedrich Boie
in 1822, but had been abandoned until a 2005 study confirmed the need for a separate genus for the crested terns.
These large terns breed in very dense colonies on coasts and islands, and exceptionally inland on suitable large freshwater lakes close to the coast. They nest in a ground scrape.
Thalasseus terns feed by plunge-diving for fish, almost invariably from the sea. They usually dive directly, and not from the "stepped-hover" favoured by, for example, the Arctic Tern
. The offering of fish by the male to the female is part of the courtship display.
These species have long thin sharp bills, usually a shade of yellow or orange except in the Sandwich Tern where the bill is black with a yellow tip in most subspecies. All species have a shaggy crest. In winter, the Thalasseus terns' foreheads become white.
An early Pliocene
fossil bone fragment from the northeastern United States
closely resembles a modern Royal Tern. It may be an unexpectedly early (3.7–4.8 million years before present) specimen of that species, or an ancestral member of the crested tern group.
Seabird
Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...
s in the tern
Tern
Terns are seabirds in the family Sternidae, previously considered a subfamily of the gull family Laridae . They form a lineage with the gulls and skimmers which in turn is related to skuas and auks...
family. Thalasseus signifies a "creature of the sea". It has a worldwide distribution, and many of its species are abundant and well-known birds in their ranges. This genus had originally been created by Friedrich Boie
Friedrich Boie
Friedrich Boie was a German scientist and brother of Heinrich Boie. He was born at Meldorf in Holstein and died at Kiel....
in 1822, but had been abandoned until a 2005 study confirmed the need for a separate genus for the crested terns.
These large terns breed in very dense colonies on coasts and islands, and exceptionally inland on suitable large freshwater lakes close to the coast. They nest in a ground scrape.
Thalasseus terns feed by plunge-diving for fish, almost invariably from the sea. They usually dive directly, and not from the "stepped-hover" favoured by, for example, the Arctic Tern
Arctic Tern
The Arctic Tern is a seabird of the tern family Sternidae. This bird has a circumpolar breeding distribution covering the Arctic and sub-Arctic regions of Europe, Asia, and North America...
. The offering of fish by the male to the female is part of the courtship display.
These species have long thin sharp bills, usually a shade of yellow or orange except in the Sandwich Tern where the bill is black with a yellow tip in most subspecies. All species have a shaggy crest. In winter, the Thalasseus terns' foreheads become white.
List of species in taxonomic order
- Lesser Crested TernLesser Crested TernThe Lesser Crested Tern is a seabird of the tern family Sternidae...
Thalasseus bengalensis - Royal TernRoyal TernThe Royal Tern is a seabird in the tern family Sternidae. This bird has two distinctive subspecies. T. m. maximus breeds on the Atlantic and Pacific coasts of the southern USA and Mexico into the Caribbean. The slightly smaller T. m. albididorsalis breeds in coastal west Africa...
Thalasseus maximus - Greater Crested TernGreater Crested TernThe Greater Crested Tern , also called Crested Tern or Swift Tern, is a seabird in the tern family which nests in dense colonies on coastlines and islands in the tropical and subtropical Old World...
or Swift Tern, Thalasseus bergii - Chinese Crested TernChinese Crested TernThe Chinese Crested Tern is a seabird of the tern family Sternidae, closely related to Sandwich Tern T. sandvicensis and Lesser Crested Tern T. bengalensis...
Thalasseus bernsteini - Elegant TernElegant TernThe Elegant Tern is a seabird of the tern family Sternidae. It breeds on the Pacific coasts of the southern USA and Mexico and winters south to Peru, Ecuador and Chile....
Thalasseus elegans - Sandwich Tern Thalasseus sandvicensis
An early Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
fossil bone fragment from the northeastern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
closely resembles a modern Royal Tern. It may be an unexpectedly early (3.7–4.8 million years before present) specimen of that species, or an ancestral member of the crested tern group.