Evaluation of proposed genetic goals and targets for the Convention on Biological Diversity

Abstract

In the current negotiations regarding revision of the Convention on Biological Diversity (CBD) proposals have been made to strengthen the genetic goals, indicators, and targets for wild species in natural habitats by specifying “tolerable” losses of genetic diversity. However, they have not been subjected to evaluations of their continued use over 100 years, a common conservation time frame. I evaluated six scenarios (3, 5 or 10% loss of genetic diversity [heterozygosity] over 8 or 32 years) proposed as targets for revision of genetic indicators in CBD by predicting their consequences on genetic diversity, inbreeding, fitness, and evolutionary potential when applied at the same rate for 100 years. All proposals lead to substantial genetic harm to species when continued for 100 years that will compromise species persistence, especially in the context of environmental change. Consequently, none of the proposals are suitable for inclusion in the CBD. However, alternative indicators are proposed that would reflect improvements in the genetic status of populations and species, namely (1) the number of species and their populations being maintained at sizes sufficient to retain evolutionary potential in perpetuity, and (2) the number of species for which population genetic connectivity has been improved.