Data Zone
Justification of Red List category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Population justification
The global population size of this species has not been formally estimated. The abundances of each 'subspecies group' (sensu del Hoyo and Collar 2016) is discussed separately:
The population size of 'Japanese Paradise-flycatcher' T. a. atrocaudata has not been estimated, but is described as fairly common by Chikara (2019), and citizen science data (eBird 2023) reveal it to be widespread and relatively common; see also Bird Breeding Distribution Survey Committee (2021). Similarly, 'Ryukyu Paradise-flycatcher' T. a. illex is described as fairly common by Chikara (2019) and although its population size is likely to be much smaller than T. a. atrocaudata, citizen science data show it to be widespread (eBird 2023). The population of 'Lanyu Paradise-flycatcher' T. a. periophthalmica on Lanyu was estimated as being as high as c. 1,000 breeding pairs by Späth et al. (2018) in only 12 km2 of suitable habitat. This taxon also occurs on the Batanes Islands, where descriptions of its abundance as 'common' (Allen 2020), and citizen science data (showing counts of more than 20 individuals on relatively short (<4 km) transects), indicate it is similarly common. Given the Batanes Islands contain almost 70 km2 of suitable habitat, the total population size of T. a. periophthalmica alone is likely to be several thousand mature individuals. Consequently, although the total population size is set here to unknown (owing to immense uncertainty regarding the population size of the most numerous taxon (nominate atrocaudata)), there is high confidence that it is moderately large, and exceeds (probably greatly) 10,000 mature individuals.
Trend justification
Although declines were noted historically (BirdLife International 2001), primarily owing to the loss of habitat in the 19th and 20th centuries in Japan, there is no evidence these are ongoing (Späth et al. 2018). The Japan Bird Atlas indicates an increase in the number of confirmed or likely breeding grid squares from 204 in 1997-2002 to 411 in 2016-2021 (Breeding Bird Distribution Survey Committee 2021), and on Lanyu the population was also interpreted to be increasing in parallel with the increase in habitat extent on the island (Späth et al. 2018). Elsewhere, the trend is effectively unknown, although there is little indication that the species is globally in decline. As such the population is assessed as stable or possibly increasing.
The species breeds in the humid forests of southern Honshu, Shikoku, Kyushu and the Nansei Shoto islands in Japan, South Korea, North Korea, Lanyu Island, Taiwan, China (including Lanyu Island) and the Batanes islands (where it may be resident), northern Philippines. Its wintering grounds are improperly known, but certainly include Peninsular Malaysia, and Sumatra and Java, Indonesia (see Janra et al. 2019), and the Philippines. On passage, it is recorded in a number of states including China, Viet Nam, Lao PDR, Thailand, and presumably Myanmar. It has been recorded on Borneo, and may be more regular thereon than records suggest.
This species breeds in mature deciduous or mixed forest and plantations on low hills and mountains, up to 1,000 m. In central Japan, wooded valleys at lower elevations are preferred. On the wintering grounds, records are from various forest habitats up to 700 m, including mangroves. On migration, it is also recorded from open woodland, suburban parks and gardens in lowlands.
The main threats to this species are on its wintering grounds in Indonesia and the Philippines. Here, forest loss and degradation, especially in the Sumatran lowlands, is a possible threat, although when not breeding this species appears tolerant of habitat degradation, and the stable/increasing population on its breeding grounds suggests that it is not driving population declines. In Indonesia, it is also known to have occasionally been caught for the songbird trade (Janra et al. 2019) however this is thought to be sporadic, localised and unlikely to be driving population declines. Nonetheless, this threat should continue to be closely monitored.
Conservation Actions Underway
Listed in CMS Appendix II. On its breeding, passage and wintering grounds, occurs in numerous protected areas. In some parts of its range, forest protection programmes have shown some success (e.g., Yu 2008, Späth et al. 2018). No specific action is known, although this species undoubtedly benefits from general protected area conservation.
Text account compilers
Berryman, A.
Contributors
Ashpole, J, Benstead, P., Everest, J., Gilroy, J., Khwaja, N. & Taylor, J.
Recommended citation
BirdLife International (2024) Species factsheet: Japanese Paradise-flycatcher Terpsiphone atrocaudata. Downloaded from
https://datazone.birdlife.org/species/factsheet/japanese-paradise-flycatcher-terpsiphone-atrocaudata 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.