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White-tailed tropicbird

White-tailed tropicbird
Warwick Parish, Bermuda
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Phaethontiformes
Family: Phaethontidae
Genus: Phaethon
Species:
P. lepturus
Binomial name
Phaethon lepturus
Daudin, 1802

The white-tailed tropicbird (Phaethon lepturus) or yellow-billed tropicbird 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".[2]

Taxonomy

Flying at Midway Atoll

French zoologist François Marie Daudin described the white-tailed tropicbird in 1802.[3][4]

"White-tailed tropicbird" has been designated the official name by the International Ornithologists' Union (IOC).[5]

Its closest relative is the red-tailed tropicbird (P. rubricauda), the split between their ancestors taking place about four million years ago.[6]

Six subspecies are recognised by the IOC:[5]

  • P. l. lepturus—found across the topical Indian Ocean.[5]
  • P. l. fulvus (golden bosun)—native to Christmas Island.[5] This form has a golden wash to the white plumage
  • P. l. dorotheae—tropical western Pacific[5]
  • P. l. catesbyi—Bermuda and Caribbean[5]
  • P. l. ascensionis—Ascension Island and Fernando de Noronha[5]
  • P. l. europae—Europa Island, s. Mozambique Channel[7]

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.[8] 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 keee-keee-krrrt-krrt-krrt. 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

A pair in flight
In the Seychelles

The white-tailed tropicbird feeds mainly on flying fish, squid and crabs.[9] 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.[10]

Phaethon lepturus egg, MHNT

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.[11]

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.[12]

References

  1. ^ BirdLife International (2020). "Phaethon lepturus". IUCN Red List of Threatened Species. 2020: e.T22696645A163887639. doi:10.2305/IUCN.UK.2020-3.RLTS.T22696645A163887639.en. Retrieved 27 March 2022.
  2. ^ Longtail. The Bermuda Audubon Society.
  3. ^ Lacépède, Bernard Germain de; Daudin, François Marie (1799). "Tableau des sous-classes, divisions, sous-divisions, ordres et genres des oiseaux, par le Cen Lacépède; avec l'indication de toutes les espèces décrites par Buffon, et leur distribution dans chacun des genres, par F. M. Daudin". In Buffon, Georges-Louis Leclerc de (ed.). Histoire Naturelle par Buffon Dédiée au citoyen Lacépède, membre de l'Institut National (in French). Vol. 14: Quadrupedes. Paris: P. Didot l'ainé et Firmin Didot. pp. 197–346 [319]. Although the date of 1799 is printed on the title page, this volume was not published until 1802. For a discussion of the date see: Richmond, Charles W. (1899). "On the date of Lacépède's 'Tableaux'". Auk. 16: 325–329. doi:10.2307/4069359. JSTOR 4069359.
  4. ^ Mayr, Ernst; Cottrell, G. William, eds. (1979). Check-List of Birds of the World. Vol. 1 (2nd ed.). Cambridge, Massachusetts: Museum of Comparative Zoology. p. 158.
  5. ^ a b c d e f g Gill, Frank; Donsker, David, eds. (2023). "Kagu, Sunbittern, tropicbirds, loons, penguins". World Bird List Version 13.2. International Ornithologists' Union. Retrieved 27 November 2023.
  6. ^ Kennedy, Martyn; Spencer, Hamish G (2004). "Phylogenies of the frigatebirds (Fregatidae) and tropicbirds (Phaethonidae), two divergent groups of the traditional order Pelecaniformes, inferred from mitochondrial DNA sequences". Molecular Phylogenetics and Evolution. 31 (1): 31–38. Bibcode:2004MolPE..31...31K. doi:10.1016/j.ympev.2003.07.007. PMID 15019606.
  7. ^ Corre, Matthieu Le; Cebc, Pierre Jouventin (1999). "Geographical variation in the White-tailed Tropicbird Phaethon lepturus, with the description of a new subspecies endemic to Europa Island, southern Mozambique Channel". Ibis. 141 (2): 233–239. doi:10.1111/j.1474-919X.1999.tb07546.x.
  8. ^ Redman, Nigel; Stevenson, Terry; Fanshawe, John (2016). Birds of the Horn of Africa: Ethiopia, Eritrea, Djibouti, Somalia, and Socotra - Revised and Expanded Edition. Princeton Field Guides. Princeton, New Jersey: Princeton University Press. p. 42. ISBN 978-0-691-17289-7. OCLC 944380248. Retrieved 2018-11-27.
  9. ^ "White-tailed Tropicbird | Audubon Field Guide". Audubon. Retrieved 2024-04-21.
  10. ^ "White-tailed Tropicbird". www.oiseaux-birds.com.
  11. ^ "White-tailed Tropicbird – Conservation – Neotropical Birds Online". neotropical.birds.cornell.edu. 22 November 2023.
  12. ^ Cunningham, Lawrence J. (1992). Ancient Chamorro Society. Bess Press. p. 112. ISBN 9781880188057.

Further reading

  • ffrench, Richard (1991). A Guide to the Birds of Trinidad and Tobago (2nd ed.). Comstock Publishing. ISBN 978-0-8014-9792-6.
  • Harrison, Peter (1996). Seabirds of the World. Princeton: Princeton University Press. ISBN 978-0-691-01551-4.
Quelle: https://en.wikipedia.org/wiki/White-tailed_tropicbird