Taxonomic considerations in listing subspecies under the U.S. Endangered Species Act.

Effects on species' conservation of reinterpreting the phrase "significant portion of its range" in the U.S. Endangered Species Act.

The U.S. Endangered Species Act (ESA) requires listing of a species as threatened or endangered not only when it is at risk of worldwide extinction, but also when it is at risk in any “significant portion of its range” (SPOIR) (16 U.S.C. Section 1532(6)). Many species have been listed as endangered under the ESA in part because they were threatened in a SPOIR (e.g., FWS 1990, 1995, 2000). On 16...

Geography and recovery under the U.S. Endangered Species Act.

The U.S. Endangered Species Act (ESA) defines an endangered species as one "at risk of extinction throughout all or a significant portion of its range." The prevailing interpretation of this phrase, which focuses exclusively on the overall viability of listed species without regard to their geographic distribution, has led to development of listing and recovery criteria with fundamental concept...

Subspecies and the philosophy of science

Phylogenetic methods increasingly are brought to bear on questions of subspecies taxonomy, but several recent examples highlight the need for a clear and consistent philosophical approach to how genetic data are used to assess subspecies limits. Such standards are crucial conceptually, whether or not taxonomic decisions affect conservation decisions, as they might in a recent study focused on t...

The Effectiveness of Listing under the U.S. Endangered Species Act An econometric analysis using matching methods

The endangered quino checkerspot butterfly, Euphydryas editha quino (Lepidoptera: Nymphalidae)

With the listing of the quino checkerspot butterfly, Euphydryas editha quino, as a federally endangered species, research into its ecology and conservation is necessary to allow for recovery planning and management. We review systematics, distribution, natural history, and conservation prospects, with reference to pertinent literature about other E. editha subspecies. Additional information is ...