Résumé
Designing conservation interventions for rare species can be hindered by a lack of relevant data. Local ecological knowledge (LEK) has potential to provide rapidly collected, cost-effective data across large spatio-temporal scales, but has rarely been used as a source of conservation-relevant information for the Asian Songbird Crisis. The Blue-crowned Laughingthrush (Pterorhinus courtoisi; BCLT) is a Critically Endangered passerine found only in southeastern China. It is unclear why the species' breeding range and global population are extremely small, as it occurs in human-occupied forest-agricultural landscapes similar to surrounding environments across southern China. We conducted systematic range-wide interviews on BCLT (n = 519) to collect novel information on the species' temporal and spatial distribution, and on potential human activities and landscape changes associated with its presence or absence. Recognition of BCLT was moderate (45.0% of respondents reported sightings), with sightings within the previous 18 months across the study area, within and beyond their known distribution. Over half of known breeding villages were confirmed by LEK data, and nesting was reported from two villages with no previous breeding records. BCLT trapping was reported across the study landscape, mostly from the last decade and associated with trappers from urban centres. BCLT trapping and lack of fengshui forest were associated with sites where BCLTs did not breed. Breeding sites were associated with increases in vegetable gardens over respondents' lifetimes, and other sites within the species' range were associated with decreases in bush/scrub. We demonstrate that LEK can identify potential threats, new breeding sites and landscape changes correlated with species presence or absence for threatened birds affected by the Asian songbird crisis. This study provides the first evidence of ongoing trapping as a threat to BCLT, and remedial measures are urgently required across the region.