Data Zone
Justification of Red List category
This grassland specialist has a small, rapidly declining population owing to the loss and degradation of the tall, dense grassland with wet soil on which it is totally dependent, primarily through drainage and conversion to agriculture. It therefore qualifies as Vulnerable.
Population justification
The population size of this species is difficult to estimate because it is easily overlooked outside of the breeding season. An analysis of detailed accounts in BirdLife International (2001) tentatively suggests that total population may number fewer than 10,000 individuals, and so it is placed in the band 2,500-9,999 mature individuals. This equates to 3,750-14,999 individuals, rounded here to 3,500-15,000 individuals.
Trend justification
A rapid and on-going decline is suspected, owing to the many active and continuing threats impacting the population.
This species is endemic to the Indian Subcontinent, where it is patchily and locally distributed in Bangladesh, India, Nepal, and Pakistan (BirdLife International 2001, M. M. H. Khan in litt. 2016). 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, Uttarakhand, Uttar Pradesh, Haryana, Gujarat, Assam and Arunachal Pradesh (A. Rahmani in litt. 2016), as well as Delhi, Punjab, Maharashtra and Kerala, India and recently north-east, north-west and central Bangladesh (M. M. H. Khan in litt. 2016). The species was recorded in Gujarat in August 2010, apparently for the first time since 1876 (indianaturewatch.net). Its movements are not fully clear but is thought to be mainly a breeding visitor in the north of its range, including north-east India, Nepal and Bangladesh (Rahmani 2016). Recent photographs from Katampally and Kole Wetlands in February-March indicate that the species winters as far south as Kerala, and has evaded detection owing to its secretive behaviour (per Praveen J. in litt. 2012). Records of a single bird at a site in Kerala have been made in December, January, February and March over the period 2008-2010 (Rajeevan and Khaleel 2012). It was found in four or five sites during grassland surveys in Assam and Arunachal Pradesh in 2015-2016 and c.20 individuals were found in 2010 near Joka, Kolkata in West Bengal which could represent a possible breeding site (S. Sen pers. comm. to Rahmani 2012, A. Rahmani in litt. 2016). It is now usually found in small numbers. In Nepal the species is mainly a summer visitor, with the population estimated at 1,600-3.200 individuals (Inskipp et al. 2016). In Bangladesh the species was rediscovered in April 2014 in Tanguar Haor in the north-east of the country after an interval of more than 100 years (Haque and Tareq 2014). In April 2015 the species was again recorded at Tanguar Hoar and at two more sites in the north-east: Boalar Haor and Pashua Haor (Khan et al. 2015). In 2015 and 2016 the bird was recorded in the Padma (i.e. Ganges) riverbed of Dhaka Division, central Bangladesh (R. Halder pers. comm. to M. M. H. Khan in litt. 2016, E. U. Haque pers. comm. to P. Thompson in litt. 2016), and many birds were seen in June 2016 in the upper Padma area of Rajshahi Division, north-west Bangladesh (M. M. H. Khan in litt. 2016), indicating that the bird is probably more widely distributed and more common than previously assumed. The population in Bangladesh is estimated at approximately 500 individuals (M. M. H. Khan in litt. 2016), these new records are likely to represent an increase in observer effort rather than a population increase (P. Thompson in litt. 2016). The species has only been seen in the breeding season (mainly April-June) in Bangladesh thus the species may only be present during the breeding season, however it is also possible that it is resident throughout the year but difficult to see during the non-breeding season (M. M. H. Khan in litt. 2016).
The species is totally dependent on tall, dense grassland with wet soils (Rahmani 2016). It inhabits tall grassland (often dominated by Imperata and Saccharum species) and reed Phragmites, particularly in riverine and swampy areas, and intermixed with low thorny scrub or standing crops of rice. In Nepal, it occurs in relatively open, short grasslands, mostly on dry soils, but also in moist areas with tall reeds and scattered bushes. It is generally encountered singly or in pairs and is difficult to observe, except when song-flighting or breeding in May-September. In Corbett National Park, Uttarakhand, pairs have been observed in courtship in May, with the presence of juvenile birds recorded in July (M. Sharma in litt. 2012). The species has been recorded song-flighting in March-June (P. Thompson in litt. 2016). In Assam it is thought to be breed from March to May, possibly up to June (Rahmani 2016). In Tanguar Haor, north-east Bangladesh an active nest was found in April. It consisted of a semi-ball structure made of grass and found approximately 8 cm from the ground at the base of grasses (M. M. H. Khan in litt. 2016). The species has been recorded breeding in Uttar Pradesh during August-October, and observations suggest that some males may be polygamous (Arya 2010). It nests on the ground in dense vegetation (Arya 2010). It makes some nomadic local movements in response to rainfall patterns, often appearing at sites for only a few months then disappearing again. The lack of records during mist-netting surveys in the winter in Bangladesh haors where it has been recorded breeding raises the possibility of local or more distant movements (P. Thompson in litt. 2016).
Large tracts of natural swamp and wet grassland have been destroyed or degraded across its range, as a result of drainage and conversion for agriculture, and most remaining habitat is subject to intense pressure from human encroachment, fire, grass harvesting, grazing by domestic livestock, commercial forestry plantations, dam projects and irrigation schemes. In Nepal the species is threatened by habitat loss and degradation both within and outside protected areas as well as disturbance, and in Chitwan National Park, the invasive weed Mikania micrantha (Singh and Nepal 2011 in Inskipp et al. 2016).
Conservation Actions Underway
There are recent records from several protected areas, including Sultanpur National Park, Haryana, Manas, Rajiv Gandhi Orang and Kaziranga National Parks, Assam, Okhla Bird Sanctuary, Uttar Pradesh, Corbett National Park, Uttarakhand, and Chitwan National Park, Sukla Phanta and Koshi Tappu Wildlife Reserves, Nepal as well as Tanguar Haor Ecologically Critical Area, Bangladesh.
20 cm. Large, dark-streaked, buffy-brown warbler with relatively short, thick bill. Similar spp. Striated Grassbird M. palustris has longer, narrow bill, more pronounced supercilium and somewhat longer, narrower tail. Voice Song is monotonously repeated trew-treuw usually given in circling display above territory. Hints Look for males song-flighting in breeding season.
Text account compilers
Gilroy, J., Taylor, J., Benstead, P., Ashpole, J
Contributors
Baral, H., Haque, E., Khan, M., Thompson, P., Jayadevan, P., Inskipp, C., Rahmani, A., Choudhury, A., Sharma, M.
Recommended citation
BirdLife International (2024) Species factsheet: Bristled Grassbird Schoenicola striatus. Downloaded from
https://datazone.birdlife.org/species/factsheet/bristled-grassbird-schoenicola-striatus on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/11/2024.