Data Zone
Justification of Red List category
This species is restricted to the Pacific coast of South America from central Ecuador south through Peru to northernmost Chile. It is patchily distributed across this large area with a population size estimated to number only 2,700-3,600 mature individuals. The trend is inferred to be declining, the proximate causes of which are poorly known but habitat loss and degradation, and locally perhaps trade, are thought to be likely contributors. Because its population is small and declining, it is thought to be at a high risk of extinction, and is therefore classified as Vulnerable.
Population justification
Population size estimated to be relatively small. Boyla and Estrada (2005) estimated the global population to be less than 10,000 individuals, with a more recent appraisal (Lesterhuis et al. in prep.) more precisely estimating 4,550 individuals by collating published estimates, eBird data, and national censuses. Because this estimate represents a mix of data sources from different times of year, it is difficult to determine the percentage of these that are likely to refer to mature individuals. Between 20% and 40% are suspected to be immatures, leaving 2,730-3,640 mature individuals, rounded here to 2,700-3,600.
Trend justification
Population trend somewhat uncertain, but inferred to be declining. In Peru and Chile, Camacho (2010) estimated using collated observations from birding trip reports that mean flock size declined slightly in central Peru between 2000 and 2010, and increased and then decreased (rather rapidly) in northern Chile over the same time period. In Ecuador, the species is apparently declining in response to habitat destruction and fragmentation associated with growing human communities and new petroleum fields (Camacho 2010, Hume et al. 2023), and the species is listed nationally as Endangered (Freile et al. 2019) due to a small population size and continuing decline. B. superciliaris is therefore inferred to be declining, although the rate of decline is not estimated here due to considerable uncertainties about recent trends.
Endemic to the Pacific coast of South America, from southern Ecuador, through the entire Peru coastal plain, to northernmost Chile.
Favours dry agricultural landscapes, including semi-desert and dry grasslands (Hume et al. 2023).
The exact mechanisms of decline in this species are poorly known, but habitat loss and degradation associated with agricultural and urban expansion, as well as encroaching petroleum fields, within its range have been identified as likely threats (Camacho 2010, Freile et al. 2019).
Conservation Actions Underway
No species specific action is known.
Conservation Actions Proposed
Better research plausible threats to determine what the key drivers of population decline are in this species. Instigate monitoring in all range states to understand more precisely its population trend. Establish protected areas and OECMs that safeguard viable populations of this species from identified threats.
Text account compilers
Berryman, A.
Recommended citation
BirdLife International (2025) Species factsheet: Peruvian Thick-knee Burhinus superciliaris. Downloaded from
https://datazone.birdlife.org/species/factsheet/peruvian-thick-knee-burhinus-superciliaris on 15/01/2025.
Recommended citation for factsheets for more than one species: BirdLife International (2025) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 15/01/2025.