Endangered Species Law & Policy

The journal Conservation Biology recently posted a forthcoming article on their website that I co-authored with Drs. Dennis Murphy and Kenneth Cummins entitled, A Critical Assessment of the Use of Surrogate Species in Conservation Planning in the Sacramento-San Joaquin Delta, California (U.S.A.). The principle purpose of the article is to assess the use of surrogate species in the Sacramento-San Joaquin Delta. Specifically, we examined the use of surrogate species, in the form of cross-taxon response-indicator species, that is, one species from which data are used to guide management planning for another, distinct species. In the Delta, we explain that there has been increasing reliance on surrogates in conservation planning for species listed under federal or state endangered species acts, although the agencies applying the surrogate species concept did not first validate that the surrogate and target species respond similarly to relevant environmental conditions. We note that, during the same period when there was increasing reliance on surrogates in the Delta, conservation biologists demonstrated that the surrogate concept is generally unsupported by ecological theory and empirical evidence. Further, we contend that [r]ecently developed validation procedures may allow for the productive use of surrogates in conservation planning, but, used without validation, the surrogate species concept is not a reliable planning tool.