On September 4, 2013, the U.S. Fish and Wildlife Service and National Marine Fisheries Service (collectively, the Services) issued a proposal rule to amend the regulations governing consultation under section 7 of the Endangered Species Act (ESA) that would codify the practice of using surrogates to express the amount of extent of anticipated take in an incidental take statement issued concomitant with a biological opinion. The Services indicate that these changes are proposed “to improve the flexibility and clarify the development of incidental take statements.”

Section 7(b)(4) of the ESA provides that, where an agency action and anticipated incidental take will not violate section 7(a)(2), the apposite Service shall issue an incidental take statement that, among other things, “specifies the impact of such incidental taking on the species.” The Services acknowledge in the proposed rule the congressional preference for numerical limits with respect to individuals of the listed species. At the same time, the Services reference court decisions recognizing that in some circumstance use of surrogates, or indicators, may be acceptable as an alternative to numerical estimates of individuals. The proposed rule states that “evaluating impacts to a surrogate such as habitat, ecological conditions, or similar affected species may be the most reasonable and meaningful measure of assessing take of listed species.”

The proposed rule goes on to indicate that surrogates may be used, provided the incidental take statement (or accompanying biological opinion), “(1) Describes the causal link between the surrogate and take of the listed species; (2) describes why it is not practical to express the amount or extent of anticipated take or to monitor take-related impacts in terms of individuals of the listed species; and (3) sets a clear standard for determining when the extent of taking has been exceeded.” Interestingly, the proposed rule does not make reference to the scholarly literature on surrogates, which spans more than a quarter century. A recent, in-depth, treatment of the subject is provided by Tim Caro in Conservation by Proxy (Island Press, 2010).

The Services are accepting comments on the proposed rule until November 4, 2013.