Pale-tailed barbthroat

Pale-tailed barbthroat
Conservation status
Least Concern  (IUCN 3.1) [1]
CITES Appendix II (CITES) [2]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Clade:	Strisores
Order:	Apodiformes
Family:	Trochilidae
Genus:	Threnetes
Species:	T. leucurus
Binomial name
Threnetes leucurus (Linnaeus, 1766)
Synonyms
Trochilus leucurus Linnaeus, 1766

The pale-tailed barbthroat (Threnetes leucurus) is a species of hummingbird in the family Trochilidae. It is found throughout much of the Amazon Basin from the eastern Andean foothills to the Atlantic Ocean. ^[3]

Taxonomy and systematics

The pale-tailed barbthroat was formally described by the Swedish naturalist Carl Linnaeus in 1766 in the twelfth edition of his Systema Naturae under the binomial name Trochilus leucurus. ^[4] Linnaeus based his short description on the "white-tailed humming-bird" that had been described and illustrated by the English naturalist George Edwards in 1758. ^[5] The type locality is Suriname. ^[6] The specific epithet is from the Ancient Greek leukouros meaning "white-tailed". ^[7] The pale-tailed barbthroat is now placed in the genus Threnetes that was introduced in 1852 by the English ornithologist John Gould. ^{[8] [3]}

Four subspecies are recognised: ^[3]

• T. l. cervinicauda Gould, 1855
• T. l. rufigastra Cory, 1915
• T. l. leucurus (Linnaeus, 1766)
• T. l. medianus Hellmayr, 1929

The taxonomy of the pale-tailed and sooty barbthroat (T. niger) complex is unsettled. The two were originally described as separate species, then combined under the name pale-tailed barbthroat but with the binomial T. niger, which had priority. In the early 2000s they were again split, with the two species recognized by the International Ornithological Committee (IOC), the Clements taxonomy, and BirdLife International's Handbook of the Birds of the World (HBW). However, the assignment of subspecies between them varies. The IOC and Clements assign the above four subspecies to the pale-tailed barbthroat and two others to the sooty barbthroat. HBW transfers subspecies loehkeni from the sooty to the pale-tailed, leaving the former monotypic. Other authors suggest that loehkeni should be treated as a separate species. ^{[3] [9] [10] [11] [12]}

The pale-tailed barbthroat and the other two members of its genus, band-tailed barbthroat (T. ruckeri) and sooty barbthroat (T. niger), form a superspecies. ^[13]

Description

The pale-tailed barbthroat is 10 to 12.2 cm (3.9 to 4.8 in) long. Males weigh 4 to 7 g (0.14 to 0.25 oz) and females 4 to 6.5 g (0.14 to 0.23 oz). The adult male has bronze-green upperparts and breast, a dark ear patch and throat with a reddish patch below the later, and a pale malar stripe. The tail is dark with various shades and extent of color on the outer feathers. The belly is gray with ochre tints. It has a nearly straight bill. As with other hermit hummingbirds, the sexes are similar; the female's bill is somewhat more decurved than the male's and the plumage has less contrast among the throat, breast, and belly. Young birds resemble the adult but have ochraceous feather edges. The subspecies differ somewhat in the tail and belly coloration, and there are intergrades between cervinicauda and rufigastra and between rufigastra and leucurus. ^[12]

Distribution and habitat

The subspecies of pale-tailed barbthroat are distributed thus: ^{[3] [12]}

• T. l. cervinicauda, eastern Colombia south through eastern Ecuador into northeastern Peru and east into western Amazonian Brazil
• T. l. rufigastra, eastern Peru south of the Marañón River to northern Bolivia
• T. l. leucurus, southern and eastern Venezuela through Guyana, Suriname, and Amazonian Brazil to northeastern Bolivia (but not confirmed in French Guiana) ^[14]
• T. l. medianus, northeastern Amazonian Brazil south of the Amazon

The pale-tailed barbthroat inhabits open and semi-open spaces within humid lowland and higher tropical forest, and other landscapes such as gallery forest, várzea and igapó swamp forests, and plantations. It is found from sea level to 850 m (2,790 ft) in Venezuela, in Peru mainly to 1,200 m (3,900 ft) but as high as 1,800 m (5,900 ft), and in Ecuador mainly to 1,100 m (3,600 ft) and as high as 1,600 m (5,200 ft). ^[12]

Behavior

Movement

The pale-tailed barbthroat is presumed to be a year round resident throughout its range. ^[12]

Feeding

Like other hermit hummingbirds, the pale-tailed barbthroat is a "trap-line" feeder, visiting a circuit of flowering plants. It feeds on nectar at Heliconia and several other tubular flowers and also on small arthropods. ^[12]

Breeding

The pale-tailed barbthroat's nesting season varies widely across its range. Its nest is a cone-shaped cup of plant and other fibers and cobweb, covered with lichens, and attached to the underside tip of a long drooping leaf such as a palm frond. The female alone incubates the white eggs. ^[12]

Songs and calls Listen to pale-tailed barbthroat on xeno-canto

Vocalization

The pale-tailed barbthroat's song is "a fast high-pitched phrase of 5–10 notes repeated at intervals of several seconds". Its call is "a high-pitched sharp 'tseet', sometimes doubled." ^[12]

Status

The IUCN has assessed the pale-tailed barbthroat as being of Least Concern. It has a very large range, and though its population has not been quantified it is believed to be stable. ^[1] It is considered local and uncommon throughout its range and occurs in several protected areas. ^[12]

References

1. BirdLife International (2018). "Pale-tailed Barbthroat Threnetes leucurus". IUCN Red List of Threatened Species . 2018. Retrieved 15 November 2021.
2. "Appendices | CITES". cites.org. Retrieved 2022-01-14.
3. Gill, F.; Donsker, D.; Rasmussen, P. (July 2021). "IOC World Bird List (v 11.2)" . Retrieved July 14, 2021.
4. Linnaeus, Carl (1766). Systema naturae : per regna tria natura, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in Latin). Vol. 1, Part 1 (12th ed.). Holmiae (Stockholm): Laurentii Salvii. p. 190.
5. Edwards, George (1758). Gleanings of Natural History, exhibiting figures of quadrupeds, birds, insects, plants &c... (in English and French). Vol. Part 1. London: Printed for the author, at the College of Physicians. pp. 99–100, Plate 256.
6. Peters, James Lee, ed. (1945). Check-List of Birds of the World. Vol. 5. Cambridge, Massachusetts: Harvard University Press. p. 6.
7. Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. p. 225. ISBN   978-1-4081-2501-4.
8. Gould, John (1852). A Monograph of the Trochilidae, or Family of Humming-Birds. Vol. 1. London: self. Plates 13, 15 and text (Part 4 Plates 14, 15). The 5 volumes were issued in 25 parts between 1849 and 1861. Title pages of all volumes bear the date of 1861.
9. Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, J. A. Gerbracht, D. Lepage, B. L. Sullivan, and C. L. Wood. 2021. The eBird/Clements checklist of Birds of the World: v2021. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ Retrieved August 25, 2021
10. HBW and BirdLife International (2020) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world Version 5. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v5_Dec20.zip [.xls zipped 1 MB] retrieved May 27, 2021
11. Stotz, Doug (November 2003). "Proposal (77) to South American Classification Committee: Split Threnetes leucurus from Threnetes niger". South American Classification Committee, American Ornithologists' Union. Retrieved 7 March 2021.
12. del Hoyo, J., N. Collar, and G. M. Kirwan (2020). Pale-tailed Barbthroat (Threnetes leucurus), version 1.0. In Birds of the World (S. M. Billerman, B. K. Keeney, P. G. Rodewald, and T. S. Schulenberg, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.patbar1.01 retrieved November 15, 2021
13. Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 24 August 2021. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved August 24, 2021
14. Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 24 August 2021. Species Lists of Birds for South American Countries and Territories. https://www.museum.lsu.edu/~Remsen/SACCCountryLists.htm retrieved August 24, 2021

External links

• Stamps ^[usurped] (for Suriname)
• Pale-tailed Barbthroat photo gallery VIREO