Bird of the Day: Bristled Grassbird (Chaetornis striata – Jerdon, 1841)

The Bristled Grassbird (Chaetornis striata – Jerdon, 1841)  is rapidly declining owing to loss and degradation of its grassland habitat, primarily through drainage and conversion to agriculture in India subcontinent. It therefore qualifies as Vulnerable (A2c; A3c; A4c; C2a(i) ) species as per Birdlife International.

Bristled Grassbird (Chaetornis striata)

It was described by T.C. Jerdon in “Jerdon T. C. (1841) Catalogue of the birds of the peninsula of India Page 198″ as Megalurus straitus from Nilgiris (= Neilgherries) from a specimen shot by shikari.

Shortly afterwards, Blyth found “two curious small marsh birds in the bazaar” of Calcutta, describing one as “Dasyornis? locustelloides” and the other as “Dasyornis? colluriceps”. He must have read Jerdon’s description just before his report was printed, however, because in a footnote he referred to locustelloides being the same as striatus. In fact, after procuring three more in the next two years, Blyth realised that the first two birds had been males and females of the same species, now called Chaetornis striatus (Inskipp 1996).

Although a very confusing situation where this taxon is often cited to 1841, 1844, or 1845, as well as being cited to different page numbers. This confusion arises from a peculiar publishing history that has recently been clarified, though some mysteries still remain. For a discussion of this complex case, see Dickinson EC, et al.. 2004. “The dating of names proposed in the first Supplement to Thomas Jerdon’s Catalogue of the birds of the peninsula of India.“. Bull.Zool.Nomen. 61(4):214-224.

Baker (1924) termed it Chaetornis locustelloides, while Ali and Ripley (1973a) termed it Chaetornis striatus, Bristled Grass Warbler. Sibley and Monroe (1990, 1993), Roberts (1992), Grimmett et al., (1998), and BirdLife International (2001, 2010) have called it Bristled Grassbird Chaetornis striatus. Rasmussen and Anderton (2005) and del Hoyo et al. (2006) call it Chaetornis striata, based on the gender agreement of name (David and Gosselin 2002b).

Formerly placed in the “Old World warbler” family Sylviidae, its true affiliations have not been restudied. From its external morphology, it might belong to the newly-established grass warbler family Megaluridae.

Bristled Grassbird (Chaetornis striata)

The origin of its name has an interesting background. The name of the genus Chaetornis is derived from Greek khaite, long, flowing hair; ornis, a bird. This refers to the rectal bristles of this bird. Whistler (1929,JBNHS 33: 783) described the importance of these strong bristles as follows:”Five very strong bristles are set in loose movable flap of skin so that they move backwards and forwards as on a hing covers the eyes completely with a grating and afford adequate protection while the bird moves through heavy rough edged grass”. Striata is Latin for striped, streaked (stria, line) (Jobling 2009).

 

Chaetornis striata is endemic to the Indian subcontinent, where it is patchily and locally distributed in India, Nepal, and Pakistan. Formerly described as common in at least Gujarat, Andhra Pradesh and West Bengal (India) and parts of Bangladesh, it has evidently declined. Recent records come from Pakistan, the terai of Nepal, Uttar Pradesh and Assam, as well as Delhi, Punjab and Maharashtra, India. It is now usually found in small numbers.

Bristled Grassbird (Chaetornis striata)

It is a large (20 cm) chiefly brown warbler with thick streaked on upper part and fine streaks on lower throat, and unmarked buffy underparts. It has relatively short, thick bill and a very pale supercilium. It has a heavy broad rounded tail with whitish wash, and pale uppertail with distinct heavy black central stripe. Male is larger with rufescent forecrown and dark bill in breeding season, female has browner forecrown and paler bill. Female appears to be paler than the male and her bill is not so solidly black. The genus Chaetornis is characterized by having unfeathered lores and five exceptionally strong rectal bristles arranged in a vertical row in front of the eyes. Sexes are similar, but male is about 10% larger than female.

 

During my Photography trip to Naliya Region of Kutch from 21-08-2010 to 23-08-2010,

I had come across 7 individuals of Bristled Grassbird (Chaetornis striata) (5 Males and 2 Females).

After the first sighting of this species on 21st I had exclusively spent remaining days to search for more individuals and marking their territories though GPS.

Bristled Grassbird (Chaetornis striata)

For Gujarat it’s been sighted almost 134 years after.

Inskipp (1996) has mentioned that although it has a wide distribution in the Indian subcontinent, there are not many records. He was able to trace only 32 references with original information and only a handful in the last 25 years.

There are no records of this species after 1876 in Gujarat.  Formerly described as common in at least Gujarat, Andhra Pradesh and West Bengal (India) and parts of Bangladesh.

Earlier records are given below.

  • Deesa (Disa), August–September 1876 (Butler 1875–1877, three males in BMNH, one egg in BMNH);
  • Ajwa, near Vadodara (Baroda), breeding, undated

Gallery Album: Bristled Grassbird (Chaetornis striata – Jerdon, 1841) 

Indian Roller (Coracias benghalensis)
Indian Roller (Coracias benghalensis)
Indian Roller (Coracias benghalensis)

Further Reading:

  • Ali, S. & Ripley, D. (1987) Handbook of the Birds of India & Pakistan. Compact Ed. Bombay: OUP.
  • Baker, E.C.S. (1922-31) Fauna of British India. BIRDS (Vols. I-8). London: Taylor and Francis.
  • Baker, E.C.S. (1932-35) The Nidification of Birds of the Indian Empire. (Vols.1-4) London: Taylor and Francis.
  • Baker, K. (1997) Warblers of Europe, Asia and North Africa. Christopher Helm and A&C Black, London.
  • Barua, M. (2005) Kaziranga. Birding Hotspots. BirdingAsia:Bulletin of the Oriental Bird Club 3: 28-34.
  • BirdLife International (2001) Threatened Birds of Asia: The BirdLife International Red Data Book. 2 vols. BirdLife International, Cambridge, U.K.
  • BirdLife International (2010) Species factsheet:Chaetornis striata. Downloaded from http://www.birdlife.org on 06/07/2011
  • Burg, G. et al. (1994) Ornithology of the Indian Subcontinent 1872-1992. An annotated Bibliography. Washington DC: Smithsonian Institution.
  • Cripps, J.R. (1878) First list of the birds of Furredpore, eastern Bengal. Stray Feathers 7:238-315.
  • del Hoyo, J., Elliott, A., and Christie, D. eds. (2006) Handbook of the Birds of the World. Vol. 11: Old World Flycatchers to Old World Warblers. Lynx Edicions, Barcelona.
  • Dharmakumarsinhji, R.S. (1954) Birds of Saurashtra. Bombay: TOI Press.
  • Grewal, B. (1995) Threatened Birds of India. New Delhi.
  • Grewal, B. (1996) Bristled Grassbird Chaetornis striatus at Okhla, Delhi. Oriental Bird Club Bulletin 24: 43-44. 1996.
  • Grimmet, R Inskipp, T., & Inskipp, C. (1998) Birds of the Indian Subcontinent. UK: A&C Black.
  • Heath, , P.J. and Thorns, D.M. (1989) Bristled Grass Warbler Chaetornis striatus new to and breeding in Nepal, and its separation from Large Grass Warbler Graminicola bengalensis. Forktail 4: 118-121.
  • Hume, A.O. and Oates, E.W. (1889) Nests and eggs of Indian birds, Vol. 1. Second Edition. R.H. Porter, London.
  • Inskipp, C. and Inskipp, T. (1991) A Guide to the Birds of Nepal. Second edition. Christopher Helm and A&C Black, London.
  • Inskipp, T. (1996) Little Known Oriental Bird: Bristled Grassbird Chaetornis striatus. Oriental Bird Club Bulletin 24: 46-47.
  • Jerdon, T.C. (1862-64) The Birds of India: A Natural History. Vols. I-3. Calcutta: The Military Orphan Press.
  • Kazmierczak, K. & van Perlo, B. (2000) A Field-Guide to the Birds of the Indian Subcontinent. UK: Pica Press
  • Murray, J.A. (1888) Indian Birds or the Avifauna of British India. Vols. I-2. London: Trubner & Co.
  • Oates, E.W. & Blandford (1889-98) Fauna of British India Birds. Vols.1-4. London: Taylor & Francis.
  • Pittie, A (2005) A Bibliographic index to the birds of South Asia (3rd Ed) Hyderabad (CD ROM)
  • Pittie, A. (1995) A Bibliographic Index to the Ornithology of the Indian Region. Part 1. Hyderabad:
  • Rasmussen, P & Anderton, J (2005) Birds of South Asia: The Ripley Guide, Barcelona: Lynx Editions.
  • Ripley, D. (1982) A Synopsis of the Birds of India and Pakistan. Bombay: BNHS.
  • Roberts, T.J. (1991-92) The Birds of Pakistan. Vols. I-2. Karachi: OUP.
  • Sharma, M. (2007) Bristled Grassbird Chaetornis striatus in Corbett National Park, India. BirdingASIA 7: 90-91.
  • Sharma, M. (2008) Status and conservation of Bristled Grassbird Chaetornis striata in Corbett National Park. JBNHS 105 (3): 339-341.
  • Urfi, A. J. (2003) The birds of Okhla barrage bird sanctuary, Delhi, India. Forktail 19:39-50.