Chestnut-capped Laughingthrush (Garrulax mitratus) is currently considered Least Concern, as it has not been thought to approach any of the thresholds for listing as Vulnerable; the Extent of Occurrence is considerably in excess of 20,000 km2, and while the global population is presently unknown it is considered to be in excess of the thresholds for consideration under Criterion C (fewer than 10,000 mature individuals). The species has been characterised as common (Collar and Robson 2017). However, due to ongoing habitat destruction and fragmentation the population was suspected to be in decline.
Recent information on the extent and scope of trapping for the cagebird trade in Indonesia (and Sumatra in particular) prompted a revision of the status of numerous Sumatran species for the 2016 Red List (see the topics listed here). The present species was not included due to a lack of specific information on the impact of trapping. However, it has recently been identified as being highly sensitive to trapping (Harris et al. 2016). Field surveys carried out in montane forests in northern Sumatra failed to find the species where trappers indicate that it previously occurred (Harris et al. 2016), and while it is still observed at scattered sites within Sumatra it is suspected of having undergone a moderately rapid to rapid decline in Sumatra within the most recent three generations (c.14 years). Trends in the Peninsular Malaysia population are unquantified; although the rate of forest loss and degradation is suspected of driving at best slow declines, the extent and impact of any trapping in areas here is likely to be low as it principally occurs in protected areas within the country.
Therefore there appears to be evidence that the species has undergone significant declines in Sumatra within the most recent three-generation period and that these declines are likely to be on-going. Overall, the rate of decline of the global population is not considered likely to exceed 30% within a three-generation period, but the rapid decline in Sumatra is sufficient to suspect a decline approaching this threshold. The proposal is that Chestnut-capped Laughingthrush be uplisted to Near Threatened as it approaches the threshold for listing as Vulnerable under criteria A2bcd+3bcd+4bcd.
Comments, observations and further information welcome.
Collar, N. & Robson, C. (2017). Chestnut-capped Laughingthrush (Garrulax mitratus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/59607 on 31 May 2017).
Harris, J.B.C., Tingley, M.W., Hua, F., Yong, D.L., Adeney, M.J., Lee, T.M., Marthy, W., Prawiradilaga, D.M., Sekercioglu, C.H., Suyadi, Winarni, N. and Wilcove, D.S. 2016. Measuring the impact of the pet trade on Indonesian birds. Conservation Biology DOI: 10.1111/cobi.12729.