Justification of Red List Category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
The population is estimated to number 10,000-15,000 individuals, roughly equating to 6,700-10,000 mature individuals.
The population is suspected to be in decline owing to ongoing habitat destruction.
This species is found from the highlands of central Peru south to Bolivia, extreme northern Chile and north-west Argentina; it is also a non-breeding visitor to the Peruvian coast (del Hoyo et al. 1992).
It is found in swampy areas, rushy pastureland, mudflats, pools and streams, but also occurs in bunch-grass on hills, sometimes far from water (del Hoyo et al. 1992).
Text account compilers
Ekstrom, J., Butchart, S., Harding, M.
BirdLife International (2021) Species factsheet: Plegadis ridgwayi. Downloaded from http://www.birdlife.org on 28/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/10/2021.