NT
Malay Whistling-thrush Myophonus robinsoni



Justification

Justification of Red List category
This species is classified as Near Threatened because the results of surveys suggest that its range and population are both rather small and are inferred to be in continuing decline. Its population size has not been estimated, but is likely to be small (<10,000 mature individuals). The species's range is in decline owing to continued habitat loss and degradation, which are inferred to be driving a decline in the population; however, it does not qualify for a higher threat category because its population is not considered to be severely fragmented or to occur at 10 locations or less.

Population justification
The population size has not been formally estimated, but recent surveys by Bakewell et al. (2010a) found no evidence against Collar's (2005) presumption that there are fewer than 10,000 mature individuals. It is placed in the band 2,500-9,999 mature individuals, equating to 3,750-14,999 individuals in total, rounded here to 3,500-15,000 individuals.

Trend justification
This species is highly forest dependent and is inferred to be declining because of ongoing habitat destruction and degradation, which has caused the species to go extinct at locations it was previously recorded (Yeap et al. 2007, D. Bakewell et al. 2010a,b, Bakewell in litt. 2021).

Distribution and population

Myophonus robinsoni is endemic to the highlands of the Main range, central peninsular Malaysia where it occurs from the Cameron Highlands south to the Genting Highlands, probably remaining uncommon to more or less common (Wells 2007). It has been recorded in at least six areas (BirdLife International 2001, Bakewell et al. 2010a, 2010b), with post-1980 records from only four of these: Bukit Larut, the Cameron Highlands Wildlife Sanctuary, Tanah Rata and Fraser's Hill (Collar 2005, Bakewell et al. 2010b, D. Bakewell in litt. 2021). However, identification of the species has been hampered by a previous lack of diagnostic criteria for separating it from the dull southern subspecies of Blue Whistling-thrush M. caeruleus dicrorhynchus (Wells 2007, Bakewell et al. 2010a). A recent study of Myophonus species in peninsular Malaysia confirmed that M. c. dicrorhynchus occurs in montane areas, an aspect of its distribution over which there had been some uncertainty and could lead to confusion with M. robinsoni (Bakewell et al. 2010a, 2010b). The surveys for this study, conducted in 2009-2010, failed to find M. robinsoni in the Cameron Highlands, however its presence here has been confirmed since (eBird 2021). However, other records (eBird 2021) greatly extending the distribution of this species to the north and south remain unconfirmed, but are possible given suitable habitat (D. Bakewell in litt. 2021). In the absence of sufficient data, the population is suspected to number fewer than 10,000 mature individuals (Collar 2005) given its small range and apparent rarity, an estimate that recent survey results suggest is realistic (Bakewell et al. 2010a); however, further research is required and confirmation of its distribution, particularly in northern Peninsular Malaysia, should be considered a priority.

Ecology

This species is resident in the ground and lower storey of hill and montane evergreen forest, usually near streams, at c.760-1,770 m. Previous mention of its occurring at c.480 m (e.g., by Collar 2005 and Puan et al. 2020) is considered erroneous (Bakewell 2010a,b) and instead refers to a record from above 1550 m. It is very shy, occasionally frequenting quiet mountain roadsides at dawn and dusk. It probably feeds on insects (Wells 2007). Nests with eggs (clutch-size 1-2) and young have been found in March and September, described as "massive half-cup" structures, which have been found in roots, ferns and behind waterfalls (Wells 2007, Teo and Wee 2009).

Threats

There are still extensive areas of intact habitat (Wells 2007), with the majority of suitable habitat in the Titiwangsa Range remaining largely undisturbed (D. Bakewell in litt. 2010). However, the species appears to be threatened by small-scale habitat loss and degradation (Yeap et al. 2007, Bakewell et al. 2010a, 2010b). Conversion of forest for agriculture around its lower altitudinal limits may be causing some declines (Bakewell et al. 2010a, 2010b). Habitat degradation is caused by the sedimentation and pollution of waterways - largely as a result of infrastructure development, pesticide run-off and fly-tipping of waste, as well as tree-felling for construction (largely driven by tourism), the introduction of non-native plant species, the illegal collection and hunting of fauna and flora and the local climatic effects of over-development and vegetation removal (Yeap et al. 2007, Bakewell et al. 2010a, 2010b). Given its montane distribution, this species may be affected by climate change in the future.

Conservation actions

Conservation Actions Underway
The species occurs in Fraser's Hill Wildlife Reserve and the Malayan Nature Society Boh Tea Estate Centre; however, it is uncertain how strong the protection of habitat is in these areas (Collar 2005). The Cameron Highlands Wildlife Sanctuary has been degazetted (Yeap et al. 2007).

Conservation Actions Proposed
Search for the species in suitable habitat and where there have been previous records. Carry out surveys and monitoring in order to estimate the population size and rate of decline. Increase the area of suitable habitat with protected status. Lobby for increased restrictions on tourist developments. Conduct surveys to search for this species both north and south of its known distribution given the availability of suitable habitat.

Identification

25-26 cm. Medium-sized, dark thrush. Mainly dark black-blue plumage. Bright metallic blue lesser coverts and base of median coverts to wing-bend. Juvenile generally sootier black. Similar spp. Blue Whistling-thrush M. caeruleus is larger, heavier-billed and proportionally shorter-tailed, with dull whitish median covert tips and bluish speckles on mantle, scapulars, sides of head and throat. Voice Soft mix of fluty and scratchy notes. Call a loud, thin tsee.

Acknowledgements

Text account compilers
Harding, M., Berryman, A., Taylor, J., Khwaja, N., Benstead, P.

Contributors
Bakewell, D. & Wells, D.R.


Recommended citation
BirdLife International (2024) Species factsheet: Malay Whistling-thrush Myophonus robinsoni. Downloaded from https://datazone.birdlife.org/species/factsheet/malay-whistling-thrush-myophonus-robinsoni on 07/12/2024.
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 07/12/2024.