The SAFE index: using a threshold population target to measure relative species threat
journal contribution
posted on 2023-05-19, 04:01 authored by Clements, GP, Bradshaw, CJA, Barry BrookBarry Brook, Laurance, WFThe International Union for Conservation of Nature (IUCN) Red List is arguably the most popular measure of relative species threat, but its threat categories can be ambiguous (eg “Endangered” versus “Vulnerable”) and subjective, have weak quantification, and do not convey the threat status of species in relation to a minimum viable population target. We propose a heuristic measure that describes a “species' ability to forestall extinction”, or the SAFE index. We compare the abilities of the SAFE index with those of another numerically explicit metric – percentage range loss – to predict IUCN threat categories using binary and ordinal logistic regression. Generalized linear models showed that the SAFE index was a better predictor of IUCN threat categories than was percentage range loss. We therefore advocate use of the SAFE index, possibly in conjunction with IUCN threat categories, because the former indicates the “distance from extinction” of a species, while implicitly incorporating population viability as a variable.
History
Publication title
Frontiers in Ecology and the EnvironmentVolume
9Issue
9Pagination
521-525ISSN
1540-9295Department/School
School of Natural SciencesPublisher
John Wiley & Sons, IncPlace of publication
111 River St, Hoboken, NJ 07030 United StatesRights statement
Copyright 2011 The Ecological Society of AmericaRepository Status
- Open