It may seem curious to some that the survival of a relatively small number of three-inch fish among all the countless millions of species extant would require the permanent halting of a virtually completed dam for which Congress has expended more than $ 100 million…. We conclude, however, that the explicit provisions of the Endangered Species Act require precisely that result.

Tennessee Valley Authority v. Hill, 437 U.S. 153, 172-73, 8 ELR 20513, 20517 (1978) (TVA v. Hill).

The broad purpose of the ESA supports the Secretary's decision to extend protection against activities that cause the precise harms Congress enacted the statute to avoid…. Among its central purposes is "to provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved…."

….

… As all recognize, the Act encompasses a vast range of economic and social enterprises and endeavors.

Babbitt v. Sweet Home Chapter of Communities for a Great Oregon, 115 S. Ct. 2407, 2413, 2418, 25 ELR 21194, 21196, 21199 (1995).

The substantive provisions of the Endangered Species Act (ESA)¹ have been construed by the U.S. Supreme Court on only two occasions.² The range of these decisions, separated by 17 years and quoted above, mirrors the evolution in the application of the ESA. In TVA v. Hill, the Court enjoined the construction of the Tellico Dam to protect the snail darter, based in part on what the Court perceived to be congressional intent to reverse the trend of species extinction, "whatever the cost." This decision demonstrates the initial focus of both ESA litigation and agency application of the statute. In the early years of the program, the agencies implementing the Act, the public, and reviewing courts largely focused on individual species and specific projects. Recently, however, with the growing focus on concepts of conservation biology, biodiversity, and ecosystem management, administration of the ESA has increasingly turned to the conservation and management of multiple species and habitats as a common denominator. In Babbitt v. Sweet Home Chapter of Communities for a Great Oregon, the Court upheld the U.S. Fish and Wildlife Service's (FWS') regulatory interpretation of the § 9 prohibition on taking listed species as applying to significant habitat modification activities on nonfederal land.

This shifting focus of judicial application of the ESA has set the foundation for discussions concerning changes to two interrelated yet distinct aspects of ESA implementation: the scope of takings of listed species prohibited by § 9 and the constitutional limits of ESA regulation of private property without just compensation. This Dialogue examines the background of these two components of the ESA's application and reauthorization debate. First, the Dialogue provides a brief outline of the ESA statutory framework to better examine where the species taking provisions come into play, and also to identify potential sources of government regulatory authority that could lead to an uncompensated taking of private property. Second, it surveys the development of the Act's application through the case law to illustrate the growing focus on habitat and ecosystem conservation. Third, it highlights some of the current issues in ascertaining whether habitat-altering activities may constitute a prohibited § 9 taking of protected species. Lastly, it describes the Fifth Amendment's constitutional takings framework and evaluates the Fifth Amendment's potential application to ESA regulatory actions.