White-tailed tropicbird

White-tailed tropicbird
The white-tailed tropicbird (Phaethon lepturus) is a tropicbird. It is the smallest of three closely related seabirds of the tropical oceans and smallest member of the order Phaethontiformes. It is found in the tropical Atlantic, western Pacific and Indian Oceans. It also breeds on some Caribbean islands, and a few pairs have started nesting recently on Little Tobago, joining the red-billed tropicbird colony. In addition to the tropical Atlantic, it nests as far north as Bermuda, where it is locally called a "longtail".
Taxonomy
There are six subspecies:
P. l. lepturus—Indian Ocean
P. l. fulvus (golden bosun)—This form has a golden wash to the white plumage
P. l. dorotheae—tropical Pacific
P. l. catesbyi—Bermuda and Caribbean
P. l. ascensionis—Ascension Island
P. l. europae—Europa Island, s. Mozambique Channel
Description
The adult white-tailed tropicbird is a slender, mainly white bird, 71–80 cm long including the very long central tail feathers, which double its total length. The wingspan is 89–96 cm. The bird has a black band on the inner wing, a black eye-mask, and an orange-yellow to orange-red bill. The bill colour, pure white back and black wing bar distinguish this species from the red-billed tropicbird.
The white-tailed tropicbird breeds on tropical islands, laying a single egg directly onto the ground or a cliff ledge. It disperses widely across the oceans when not breeding, and sometimes wanders far. It feeds on fish and squid, caught by surface plunging, but this species is a poor swimmer. The call is a high screamed . Sexes are similar, although males on average are longer tailed, but juveniles lack the tail streamers, have a green-yellow bill, and a finely barred back. The white-tailed tropicbird does not have a yearly breeding cycle; instead, breeding frequency depends on the climate and availability of suitable breeding sites. The bird can reproduce 10 months after the last successful breeding, or 5 months after an unsuccessful one.
Behavior
The white-tailed tropicbird feeds mainly on flying fish, squid and crabs. It catches its prey by diving from height of up to 20 meters, as do gannets. However, flying fish are caught in flight. It usually feeds in pairs. Prey is often detected by hovering above the surface as the bird swallows it before taking off.
Conservation status
Population trends are unknown. In Mexico it is not under any category of protection, and no specific conservation programs for these tropicbirds are known. However, the species is found in various conservation programs as an American waterfowl. It is recommended to conduct studies on the biology of this species at sea, as well as monitoring of breeding colonies. Globally it is considered a species of Least Concern.
Folklore
The ancient Chamorro people called the white-tailed tropicbird utak or itak, and believed that when it screamed over a house it meant that someone would soon die or that an unmarried girl was pregnant. Its call would kill anyone who didn't believe in it. Chamorro fishermen would find schools of fish by watching them.
References
Further reading
External links
Species information on P.l. catesbyi
White-tailed tropicbird videos, photos & sounds on the Internet Bird Collection
Phaethontidae
Birds of the Atlantic Ocean
Birds of the Caribbean
Birds of the Dominican Republic
Birds of the Indian Ocean
Birds of the Pacific Ocean
Birds of Ascension Island
Birds of Saint Helena Island
Birds described in 1802
Taxa named by François Marie Daudin
Pantropical fauna