The bare-headed laughingthrush (Melanocichla calva) is a species of bird in the Old World babbler family Timaliidae. It is endemic to highland forests at elevations of 750–1,800 m (2,460–5,910 ft) in the mountain ranges of north-central Borneo, along with some outlying peaks. It is 25–26 cm (9.8–10.2 in) long, with both sexes similar in appearance. The head is brownish to greenish yellow and featherless. The area along the lower mandible has a bluish tinge. The rest of the body is dull blackish-brown tinged with grey. Juveniles have more feathers on the head, extending from the forehead to the crown.
| Bare-headed laughingthrush | |
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Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Timaliidae |
| Genus: | Melanocichla |
| Species: | M. calva
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| Binomial name | |
| Melanocichla calva (Sharpe, 1888)
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| Synonyms | |
Described by the British ornithologist Richard Bowdler Sharpe in 1888, the bare-headed laughingthrush was then treated as a subspecies of the black laughingthrush from 1935 to 2006, when it was restored to full species status. It feeds on insects such as crickets, cicadas, and ants in dense columns of vegetation formed by vines growing around trees. Although it is classified as being of least concern by the International Union for Conservation of Nature, it is threatened by habitat destruction and fragmentation and its population is thought to be decreasing.
Taxonomy and systematics
editThe bare-headed laughingthrush was described as Allocotops calvus by the British ornithologist Richard Bowdler Sharpe in 1888 on the basis of specimens collected from Mount Kinabalu, Borneo.[2] It was subsequently considered a subspecies of the black laughingthrush (Melanocichla lugubris) by the English zoologist Frederick Nutter Chasen in 1935 and moved into Melanocichla as Melanocichla lugubris calvus.[3] In 1946, the French-American ornithologist Jean Delacour synonymised Melanocichla with Garrulax.[4] In 2006, the British ornithologist Nigel Collar again raised the bare-headed laughingthrush to species status on the basis of differences in appearance.[5] The Spanish ornithologist Josep del Hoyo and colleagues split Garrulax into 11 different genera in 2007, placing the bare-headed and black laughingthrushes in a resurrected Melanocichla.[6]
The name of the genus, Melanocichla, is derived from the Ancient Greek melas, meaning black, and kikhlē, meaning thrush. The specific name calva is from the Neo-Latin calvus, meaning bald.[7] Bare-headed laughingthrush is the official common name designated by the International Ornithologists' Union.[8] Other common names for the species include bare-headed babbler[9] and Bornean bald laughingthrush.[10]
The bare-headed laughingthrush is one of 57 species in the Old World babbler family Timaliidae,[8] a diverse group of birds whose members are found in tropical forests in the Indian subcontinent, Southeast and East Asia, and Indonesia.[11] A 2019 phylogeny by Tianlong Cai and colleagues found the bare-headed laughingthrush to be most closely related to the black laughingthrush. These two species were further sister (most closely related) to the genus Pomatorhinus. The following cladogram shows the relationships within these two genera according to the 2019 phylogeny:[a][12]
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Description
edit
The bare-headed laughingthrush is 25–26 cm (9.8–10.2 in) long, with both sexes similar in appearance. It has a featherless brownish to greenish yellow head, with the submoustachial region (area along the lower jaw) having a bluish tinge. The rest of the body is dull blackish-brown with a grey tinge. The bill is orange-red, occasionally with a paler tip, while the iris is dark chestnut-brown. The legs are olive-brown with yellow feet. Juveniles have feathers on the forehead up to the crown, with bare skin behind the eye. It is similar to the black laughingthrush, but differs in its bare head, brownish coloration, and slightly shorter bill, wing and tail.[13][14]
Vocalisations
editThe vocalisations of the bare-headed laughingthrush are similar to those of the black laughingthrush. The song is a series of 3–22 deep, resonant ooh or hoo notes given at a frequency of 0.5 kHz. When the song is given in a duet, the ooh notes (thought to be given by males) are accompanied by loud, "comical" yow-yow or woh-woh notes or a loud, grating, mewing weeah (both thought to be given by females).[13] The latter calls are sometimes given alongside both the ooh and yow-yow notes. Other calls include a harsh, petulant queer-queer-hoop-hoop-hoop and a solitary bleat given as a contact call.[13][14]
Distribution and habitat
editEndemic to Borneo, the bare-headed laughingthrush is found in the north-central mountain ranges from Mount Kinabalu to Mount Dulit, along with outlying peaks in extreme eastern Brunei, Kalimantan (the Indonesian part of Borneo), and the Malaysian states of Sabah and Sarawak.[1][14][15] It is a montane species, inhabiting broadleaf evergreen forest, secondary forest, and disturbed habitats at elevations of 750–1,800 m (2,460–5,910 ft).[13][14] It is not migratory.[1]
Behaviour and ecology
editBare-headed laughingthrushes are usually seen in pairs or small flocks, sometimes as a part of mixed-species foraging flocks. They are less active than other species of laughingthrush.[14] The generation length of the species is 4.7 years.[1]
The species feeds on insects like crickets, cicadas, and ants. It creeps about in the lower storey or midstorey of the forest in a lethargic manner, foraging in dense columns of vegetation formed by vines growing around tree trunks. It free-falls through the vines in pursuit of falling insects, sometimes grabbing at perches. It will also occasionally hang upside down like a tit. Ants are gleaned from (plucked from the surface of) bamboo twigs, while larger insects are gleaned from bamboo leaves.[13][14]
Juveniles have been observed in July and possibly in August. Evidence from the use of playback (recorded birdsong) suggests that flocks are territorial.[13]
Status
editThe bare-headed laughingthrush is classified as being of least concern by the International Union for Conservation of Nature due to a sufficiently large range and population and a lack of significant population decline. However, it is locally common to uncommon and its population is currently thought to be decreasing.[1] It is threatened by habitat destruction and fragmentation,[1] but its mountainous habitat may give it some level of protection.[15] Although it has not been recorded being sold in markets, it may also be threatened by hunting for the cage-bird trade, which is known to affect other species of laughingthrushes in Indonesia.[15]
Notes
edit- ^ The study treated the bare-headed and black laughingthrushes as a part of Garrulax.[12]
References
edit- ^ a b c d e f BirdLife International (2018). "Garrulax calvus". IUCN Red List of Threatened Species. 2018: e.T22715617A131971038. doi:10.2305/IUCN.UK.2018-2.RLTS.T22715617A131971038.en.
- ^ Sharpe, Richard Bowdler (1883). "Further descriptions of new species of birds discovered by Mr. John Whitehead on the Mountain of Kina Balu, Northern Borneo". Ibis. 30 (4). London: Academic Press: 389. doi:10.1111/j.1474-919X.1888.tb08495.x. ISSN 0019-1019. LCCN 79010132. OCLC 1377260. Archived from the original on 2021-04-20. Retrieved 2022-03-02 – via Biodiversity Heritage Library.
- ^ Chasen, Frederick N. (1935). "A handlist of Malaysian birds: a systematic list of the birds of the Malay Peninsula, Sumatra, Borneo and Java, including the adjacent small islands". Bulletin of the Raffles Museum. 11. Singapore: Government Printing Office, Singapore: 206. doi:10.5962/bhl.title.119907. OCLC 220730327. Archived from the original on 2020-10-29. Retrieved 2022-03-02 – via Biodiversity Heritage Library.
- ^ Delacour, Jean (1946). "Notes on the taxonomy of the birds of Malaysia". Zoologica. 31 (1). New York: 4. doi:10.5962/p.184715. ISSN 0044-507X. LCCN 79009389. OCLC 1079318. S2CID 134523794. Archived from the original on 2020-11-26. Retrieved 2022-03-02 – via Biodiversity Heritage Library.
- ^ Collar, Nigel J. (2006). "A partial revision of the Asian babblers (Timaliidae)". Forktail. 22: 87. CiteSeerX 10.1.1.600.8276. Archived from the original on 2022-03-02. Retrieved 2022-03-02.
- ^ Luo, Xu; Qu, Yan Hua; Han, Lian Xian; Li, Shou Hsien; Lei, Fu Min (2009). "A phylogenetic analysis of laughingthrushes (Timaliidae: Garrulax ) and allies based on mitochondrial and nuclear DNA sequences". Zoologica Scripta. 38 (1): 9–22. doi:10.1111/j.1463-6409.2008.00355.x. S2CID 83800343. Retrieved 2022-03-02.
- ^ Jobling, James A. (2010). Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp. 86, 246. ISBN 978-1-4081-2501-4. OCLC 1040808348.
- ^ a b Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (August 2022). "Babblers & fulvettas". IOC World Bird List Version 12.2. International Ornithologists' Union. Retrieved 17 September 2022.
- ^ "Melanocichla calva (Bare-headed Laughingthrush)". Avibase. Archived from the original on 2022-03-02. Retrieved 2022-03-02.
- ^ Sheldon, Frederick H; Brown, Clare E.; Rahman, Mustafa Abdul; Guan, Khoon Tay; Moyle, Robert Glen (2013). "Ornithology of the Kelabit Highlands of Sarawak, Malaysia" (PDF). The Raffles Bulletin of Zoology. 61 (2): 846. Archived (PDF) from the original on 2022-03-02. Retrieved 2022-03-02.
- ^ Winkler, David W.; Billerman, Shawn M.; Lovette, Irby J. (2020-03-04). Billerman, Shawn M.; Keeney, Brooke K.; Rodewald, Paul G.; Schulenberg, Thomas S. (eds.). "Tree-Babblers, Scimitar-Babblers, and Allies (Timaliidae)". Birds of the World. Cornell Lab of Ornithology. doi:10.2173/bow.timali1.01. S2CID 216471306. Retrieved 2022-03-02.
- ^ a b Cai, Tianlong; Cibois, Alice; Alström, Per; Moyle, Robert G.; Kennedy, Jonathan D.; Shao, Shimiao; Zhang, Ruiying; Irestedt, Martin; Ericson, Per G.P.; Gelang, Magnus; Qu, Yanhua (2019). "Near-complete phylogeny and taxonomic revision of the world's babblers (Aves: Passeriformes)". Molecular Phylogenetics and Evolution. 130: 346–356. doi:10.1016/j.ympev.2018.10.010. PMID 30321696. S2CID 53216358.
- ^ a b c d e f Collar, Nigel; Robson, Craig (2021-08-18). Billerman, Shawn M.; Keeney, Brooke K.; Rodewald, Paul G.; Schulenberg, Thomas S. (eds.). "Bare-headed Laughingthrush (Melanocichla calva)". Birds of the World. Cornell Lab of Ornithology. doi:10.2173/bow.bahlau1.01.1. S2CID 243649277. Retrieved 2022-03-02.
- ^ a b c d e f Myers, Susan (2016). Birds of Borneo: Sabah, Sarawak, Brunei and Kalimantan. Illustrated by Richard Allen, Hilary Burn, Clive Byers, Daniel Cole, John Cox, Anthony Disley, Alan Harris, Szabolcs Kokay, Mike Langman, Ian Lewington, Andrew Mackay, Stephen Message, Christopher Schmidt, Jan Wilczur, and Tim Worfolk (Second ed.). London: Christopher Helm. p. 266. ISBN 978-1-4729-2444-5. OCLC 944318084.
- ^ a b c Burner, Ryan C.; Siani, Andrew; Boer, Chandradewana (2018-04-03). "First record of Bare-headed Laughingthrush Garrulax calvus in Kalimantan, Indonesian Borneo". Kukila. 21: 17–21. Retrieved 2022-03-02.