Endangered Species Act (7-8-08)

Untitled Document

The implementation of the Endangered Species Act (ESA) has long been a heated issue for environmentalists, industry and Congress. Partisan differences have prevented Congress from updating the act since it was due for reauthorization in 1992. ESA's impacts the geosciences through restricting land use and requiring environmental mitigation for industrial development. Many energy projects in the Western United States have been delayed or stopped because of concerns involving endangered species. Geoscientists are also involved as scientific experts in fields that intersect with endangered species studies, such as the effect of increased sedimentation and changes to stream morphology on salmon in the Pacific Northwest.  Some groups have questioned the effectiveness of ESA in light of the relatively small number of species that have been taken off the list since its enactment in 1973. Meanwhile, supporters argue that the act is successful since even fewer listed species have gone extinct. Recent focus has been on the designation of "critical habitat" for endangered species, changing the role of science in decision-making, increasing protection of listed species and providing protection and incentives for landowners affected by ESA..

Recent Action

Previous Action


The Endangered Species Act of 1973 is a comprehensive bill intended to protect threatened or endangered species. ESA itself has always been controversial among industry and environmentalists as its provisions can affect the use of both federal and non-federal lands and resources, but recently the definition of "critical habitat" has confused the issue.  The term "critical habitat" within in the Endangered Species Act allows for the protection of threatened or endangered species by setting aside a specific geographic area.  ESA states that the federal agencies must make these designations based on the best scientific data in addition to assessing the economic impact of such decisions, and Congress has not passed legislation to refine the definition of critical habitat or sound science in over thirty years.  Recent court rulings on critical habitat have confused the issue by sending contradictory messages. Some rulings charge the Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) with failing to protect endangered species, while other cases are throwing out previous litigation that sets aside critical habitat areas.  Courts that have considered science in species listing and the provision of the ESA that states the “best data available” must be used have held that an agency is not obliged to conduct studies to obtain missing data, but cannot ignore available biological information, especially if the ignored information is the most current.

Additional information on the ESA from the 109th Congress.


Contributed by Paul Schramm, 2007 AGI/AIPG Summer Intern

Background section contains information from the 107th Congress

Please send any comments or requests for information to AGI Government Affairs Program at govt@agiweb.org.

Last updated on May 14, 2007.