Normativity and the meaning of endangered: response to Waples et al. 2007.

There has been increased interest recently in better understanding the meaning of endangered species as defined in the 1973 U.S. Endangered Species Act (ESA). Waples et al. (2007) provide an account that is, in part, a reaction to a position presented by us in Vucetich et al. (2006). Here, we extend this discussion with comments focused on Waples et al. (2007). In the ESA an “endangered species” is defined as one “in danger of extinction throughout all or a significant portion of its range” (SPOIR). Although we (Vucetich et al. 2006) claim that the term SPOIR is fundamentally normative, Waples et al. develop a specific definition for the critical phrase significant portion of its range (SPOIR) and suggest that the “apparently normative language” can be a “largely scientific exercise.” If their definition is used to replace the SPOIR wording in the ESA’s definition of an endangered species, then an endangered species would be defined as one “in danger of extinction throughout all [of its range or in] geographic area(s) that contains population unit(s) that, if lost, would cause the entire species to be in danger of extinction or likely to become so in the foreseeable future.” Waples et al. appear to be motivated, at least in part, by what may be a common misunderstanding among scientists of the nature of normativity. First, however, we identify one independent concern with the solution presented by Waples et al. At the very least, the awkward and obfuscating grammar of the definition of Waples et al. is problematic. Accepting the interpretation by Waples et al. of SPOIR, however, might allow endangered species in the ESA to be redefined as a species that is either (1) “likely to become in danger of extinction in the foreseeable future” or (2) “in danger of extinction.”