Relative detectability of Canadian plant species at risk in field surveys

Accurate species detection is necessary for correct population estimates and species range assessments. Plant species at risk of extinction are particularly under‐studied with respect to detectability. To help improve detection efforts for Canadian plant species at risk of extinction, we created a database ranking 199 Canadian at‐risk vascular plants by relative detectability based on growth form, life cycle, habitat type, and flower color. The species ranked most detectable, based on our assumptions, were usually perennial and had a highly conspicuous flower color. All tree and shrub species ranked highly for detectability, while forbs varied considerably in their detectability ranking. Of the species living in open habitats, 68% scored in the top six ranks (out of 14 total ranks) while 75% of species living in closed habitats scored in the bottom three ranks. This research can help account for imperfect detection rates in future plant distribution studies and inform monitoring and management priorities.