Data Zone
Justification of Red List category
This forest-associated species is listed as Near Threatened because it is assumed to experience moderately rapid declines owing to the extensive loss of lowland forests from large areas of South-East Asia. However, its range and population size are still considered large.
Population justification
The global population size has not been quantified but is believed to be large given the range and frequency of records in suitable habitat. It is a forest-dependent species (with a predilection for riparian areas) and appears to occur only in good forest (eBird 2022). Within its range, the rate of forest conversion to plantations, primarily oil palm, has been very rapid over the past few decades (per Global Forest Watch 2022). There are recent records from remaining forested areas across the range, however the extent of suitable habitat is now considerably smaller than three generations ago. Where habitat is secure the species continues to be regularly observed (eBird 2022), though observing the species away from protected areas is becoming increasingly difficult, especially on Sumatra and the Thai-Malay Peninsula, where records are now scarce. In Thailand, all recent records are in (or in the vicinity of) the Hala Bala Wildlife Sanctuary (Treesucon and Limparungpatthanakij 2018, eBird 2022) and the population there must now be very small. Almost all records in Malaysia now come from protected areas or forest concessions, and the population is thought to be declining moderately rapidly in lowland Indonesia, although here (especially in Kalimantan), there are large tracts of suitable habitat remaining. Forest loss is much lower in Brunei, where impacts on the species may be much less severe and much of the forest here is likely to be suitable for this species. Although no accurate estimation of the species' population size has been made, it almost certainly exceeds 10,000 mature individuals based on the extent of suitable habitat remaining.
Trend justification
There are no population data available for this species from which to derive estimated rates of reduction. However, as a forest-dependent species, its population size is thought to be closely tied to the extent of available forest, thus rates of forest cover loss are here used as a proxy for population reduction. Over the past ten years (2012-2022), forest cover in this species' (elevational and geographic) range reduced by c. 20-22%, depending on the assumptions used (per Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein). There are two reasons why this may be reasonably considered an underestimate. First, it does not account for habitat degradation that is undetectable to remote sensing data, nor the impacts of fragmentation and extinction debt effects imposed on small and isolated forest blocks. Moreover, this species appears to be commonest in extreme lowland and riparian habitats, which may reasonably be expected to have undergone more rapid rates of forest loss due to their easier access to loggers. Consequently, over the past ten years, the population is suspected of having declined by 20-29%. The same rate is of reduction is also applied to the window 2016-2026, and over the next 10 years (2023-2033), although thereafter it may begin to slow as an increasing percentage of the population is contained within protected areas.
Cyornis turcosus is known from the Sundaic lowlands, occurring in peninsular Thailand; Sabah, Sarawak and peninsular Malaysia; Kalimantan and Sumatra, Indonesia, and Brunei.
This is a specialist of the Greater Sundas' lowland riparian forests. On the Malay Peninsula, it is apparently confined to forest below 200 m (Wells 2007, eBird 2022) while on Borneo it occurs to at least 500 m (Mann 2008), although Burner et al. (2018) apparently recorded it to 900 m in Brunei. It forages in the lower storeys of riverine and streamside forest by making short aerial sallies after passing insects. Breeding takes place from April until at least July.
The principal threat to this species is forest loss, mostly in response to the large-scale conversion of lowland forest oil-palm (and to a lesser extent rubber) plantations. Between 2012 and 2022, this is thought to have caused population reductions of 20-29% (per Global Forest Watch 2022). More locally, urban development and shifting agriculture may pose some risks. Like many songbirds in the Greater Sundas, Cyornis turcosus has occasionally been recorded in trade markets (e.g. Chng et al. 2016), although it appears to be rare. Using a web-scraping tool to mine data from online marketplace platforms, Okarda et al. (2022) found no listings of this species among c.105,000 advertisements. Consequently, this is considered only a minor threat likely to be causing only negligible declines. Nonetheless, other Cyornis species (cf. Cyornis banyumas) have declined rapidly in response to the songbird trade, hence this threat should be closely monitored.
Conservation Actions Underway
It occurs in a number of protected areas, including on the Malay Peninsula (e.g. Taman Negara National Park), Sumatra (e.g. Way Kambas National Park) and Borneo (numerous); see UNEP-WCMC and IUCN (2022) and eBird (2022).
Conservation Actions Proposed
Ensure that protected areas incorporate enough area of suitable habitat for this species (and others that favour riparian areas). Continue to monitor the rate of forest cover loss using remote sensing data.
Text account compilers
Berryman, A.
Contributors
Benstead, P., Bird, J. & Khwaja, N.
Recommended citation
BirdLife International (2024) Species factsheet: Malaysian Blue Flycatcher Cyornis turcosus. Downloaded from
https://datazone.birdlife.org/species/factsheet/malaysian-blue-flycatcher-cyornis-turcosus 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.