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 global population is suspected to number fewer than 50,000 mature individuals (Partners in Flight 2019); thus it is here placed in the band 20,000-49,999 mature individuals.
The species is undergoing a moderate decline (Partners in Flight 2019).
Text account compilers
Butchart, S. & Ekstrom, J.
BirdLife International (2023) Species factsheet: Vireo nelsoni. Downloaded from http://datazone.birdlife.org/species/factsheet/dwarf-vireo-vireo-nelsoni on 10/06/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 10/06/2023.