A critical assessment of the use of surrogate species in conservation planning in the Sacramento-San Joaquin Delta, California (U.S.A.)

The use of surrogates in conservation planning is commonplace in California and elsewhere.  A substantial body of empirical literature has demonstrated the limited effectiveness of surrogates as management tools unless it is first established that the target species and surrogate will respond similarly to a given set of environmental conditions.  We explain that, while the National Marine Fisheries Service historically used hatchery Chinook salmon survival data as a surrogate for wild Chinook salmon, steelhead, and green sturgeon survival, it erred by doing so without first validating that the surrogate responds in the same manner to environmental conditions as the target species.  The consequence of use of surrogates absent validation is selection of conservation actions by agencies that utilize limited resources in a manner that does not benefit the target species. For this reason, we call on federal and state agencies alike to validate surrogates before using relying on them to make resource management decisions.

Murphy DD, Weiland PS, Cummins KE. 2011. A critical assessment of the use of surrogate species in conservation planning in the Sacramento-San Joaquin Delta, California (U.S.A.). Conservation Biology 25:873-878.