Data Zone
Justification of Red List category
This species is very poorly known. It is suspected to have a population size smaller than 10,000 mature individuals, and is possibly declining (albeit probably only slowly). It is accordingly listed as Near Threatened.
Population justification
No robust population estimate has been made. In Belgaum, nests were densely distributed, with 16 nests found in only 60 ha of habitat, and a broader population density of one male per 1-2 hectares estimated (=50-100 males/km2) (Sant et al. 2017, 2018). However, this population density is considered unusually high (Krishnan 2021) and is unlikely to be representative of the species across its range. This is supported by citizen science data (eBird 2023), which has good coverage across the species' range and shows that at most sites, observers find no more than 2-3 singing males. An analysis of available records sound this species to have a range size of c. 11,200 km2 but not all of this is occupied (SoIB 2023).
Any attempt to extrapolate a global population size from these data is naturally difficult and surrounded with considerable uncertainty. A broad population size of 2,500-9,999 mature individuals is precautionarily accepted in the absence of more precise data, but this requires confirmation.
Trend justification
No data. Evidently this species has declined considerably from historical baselines, when more widespread (see BirdLife International 2001). An analysis of citizen science data to produce more recent trends was inconclusive (SoIB 2023). The main threat to this species is habitat loss and modification (Maheswaran 2001), although the extent to which this is driving declines is unclear, in part because Broad-tailed Grassbird is evidently tolerant of some degradation (Rahane et al. 2016, Sant et al. 2018, Krishnan 2021) and its cryptic nature makes it difficult to determine whether a failure to detect it is a sign of genuine absence. Precautionarily, threats identified 20 years ago (BirdLife International 2001, Maheswaran 2001) are assumed to be ongoing, at least on a local scale, such that continuing declines (albeit slow ones) are suspected. More data are urgently needed, however, particularly pertaining to this species' tolerances of grassland modification.
Schoenicola platyurus is endemic to the Western Ghats, India.
It inhabits dense, tall grass and reeds, interspersed with patchy scrub and bushes on open hillsides, sometimes on steep slopes, but particularly marshy or damp depressions around hilltops, at 900-2,000 m. At one site it has been seen to inhabit grass clumps overgrown by invasive Bracken, Pteridium sp. (most probably P. aquilinum) and Eupatorium sp. (probably E. adenophorum) (S. Subramanya in litt. 2012). It also occurs in dense screw pine Pandanus swamps, lemon grass and dwarf dates and at the edges of forest. It is generally very difficult to detect, except during the breeding season (April-September) when it climbs to prominent perches and performs song-flights. Its movements are not well known, but there are records (eBird 2023) from marshes down to sea-level suggesting that at least a proportion of the population might disperse to lower altitudes post-breeding.
This species is threatened by the mismanagement of native shola grasslands, as these habitats are little valued and many areas have been planted with exotic tree species (S. Subramanaya in litt. 2007). Grazing of grasslands is also detrimental, particularly as grazed areas are often burnt in order to encourage fresh growth, preventing the establishment of tall grass swards. Grasslands are poorly represented in the protected-area system within its range, giving cause for concern. Tourism is also a significant threat, with several resorts recently constructed near to protected areas.
Notwithstanding all of the above, there is evidence that this species is tolerant of grassland modification (see, e.g., Rahane et al. 2016, Sant et al. 2018, Krishnan 2021) and the extent to which these threats are causing declines is unknown.
Conservation Actions Underway
It is known to occur in several protected areas, including Bramhagiris Wildlife Sanctuary, Aralam Wildlife Sanctuary, Eravikulam National Park, Periyar Tiger Reserve, Kalakkad-Mundanthurai Tiger Reserve, Neyyar Wildlife Sanctuary, Peppara Wildlife Sanctuary and Silent Valley National Park.
18 cm. Large, plain warbler with whitish underparts and broad, rounded tail. Rufescent-brown upperparts when breeding, but colder and greyer when plumage worn. Faint, dark cross-bars on tail and narrow, pale supercilium that extends to just behind eye. Similar spp. Thick-billed Warbler Acrocephalus aedon resembles worn S. platyura, but lacks supercilium and has a narrower tail. Voice Sweet, shrill trill, delivered in a constant stream and ending with a few warbling and chak notes. Sharp metallic zink notes when agitated. Territorial songs are given-out from tall exposed perches that emerge above the grass. Hints Males are very vocal and visible during early breeding season, so the best time to survey for the species is between the end of April and late May, just before the onset of monsoon rains. Later in monsoon, weather conditions can hamper access to suitable habitats.
Text account compilers
Berryman, A.
Contributors
Subramanya, S., Praveen, J. & Vinod, U.
Recommended citation
BirdLife International (2024) Species factsheet: Broad-tailed Grassbird Schoenicola platyurus. Downloaded from
https://datazone.birdlife.org/species/factsheet/broad-tailed-grassbird-schoenicola-platyurus on 23/12/2024.
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 23/12/2024.