Scientific Name: Vermivora chrysoptera
1% of the global population estimate. This threshold is used to identify trigger species and IBAs under categories A4i/ii and A4iv.
1% of the regional/continental population estimate.
This threshold is static and standardized: Passeriformes (e.g. perching/songbirds) = 90 individuals (or 30 pairs); non-Passeriformes = 30 individuals (or 10 pairs). Only species listed by the IUCN as Vulnerable are presently eligible.
The sub-regional/national SAR threshold = 1% of the COSEWIC population estimate for the region (provinces/territories) in which the species is listed as being at risk. This threshold is used to identify trigger species and IBAs under criterion C1.
|Carden Alvar (ON040)|