Management cryptic threats genetic erosion, inbreeding depression maladaptation

Management of the cryptic threats of genetic erosion, inbreeding depression, and maladaptation

Deborah Rogers
Center for Natural Lands Management

Even when the primary objective of wildland ecosystems is protection and conservation of native species and ecological processes, it is challenging to maintain the components that comprise a natural system. Genetic diversity is one of those management challenges – cryptic, always changing, and often only signaling a problem when it has reached a critical point. Plant genomics promises to make more efficient the process of assessing adaptive genetic diversity but we still have large potentials in applying available conservation genetic principles. The objective is to provide illustrations of applying genetic principles to conservation and restoration and to review recent literature for specific examples. Principles will be revisited in the context of rapid climate change, where uncertainty remains of the rationale for moving plant materials in anticipation of specific climatic changes. As genetic study results amass for California native plants, it is clear that more genetic diversity and structuring remains than might be predicted for some rare or listed species. Further, variable ploidy within a species is a genetic feature that is rarely taken into account with restoration projects yet is quite common. Genetic diversity is more important than ever in its role of providing a means to adapt to changing conditions-whether they are natural or anthropogenic in origin. Whether we manage for and support that diversity, or undermine it by lack of consideration or inappropriate application of information or misguided assumptions, can have a substantial impact on the longevity of native plant species and resilience of our wildland ecosystems.