US Geological Survey


Date of this Version



Published in The Endangered Species Act at Thirty, Volume 1: Renewing The Conservation Promise, edited by Dale D. Goble, J. Michael Scott, & Frank W. Davis (Washington: Island Press, 2006), pp. 16–35.


The current endangered species list has its administrative beginnings in 1964 when the Department of the Interior's Committee on Rare and Endangered Wildlife Species published a preliminary list of 62 species at risk of extinction (Goble, forthcoming). Following the enactment of the Endangered Species Preservation Act of 1966 (ESPA), the secretary of the interior in 1967 published the first official list of 78 "native fish and wildlife threatened with extinction" (ESPA sec. l(c); U.S. Department of the Interior 1967; Wilcove and McMillan, this volume). By the time the Endangered Species Act (ESA) was adopted in 1973, there were 392 species on the list (Yaffee 1982). These first lists included only vertebrate species. On the thirtieth anniversary of the ESA, the number stood at 1,260 domestic species and 558 foreign species (USFWS 2003a), with plant and invertebrate species outnumbering vertebrates.

This chapter presents a graphical summary encapsulating thirty years of species protection and restoration under the ESA. The summary reveals both gains and losses. For some species, such as the Aleutian Canada goose (Branta canadensis leucopareia), the process worked as it was meant to, reversing decline and restoring populations to healthy levels (USFWS 2001a); for others, such as the dusky seaside sparrow (Ammodramus maritimus nigrescens), the process failed, and despite being listed the species continued to spiral toward eventual extinction (USFWS 1983; Walters 1992).

What follows is an assessment of the state of species protection as it has evolved under the ESA. This includes the taxonomie and demographie distribution of listed species, and the number of critical habitat designations. We also examine newer legal tools for conserving habitat on private land (such as habitat conservation plans), various measures of the act's success, and funding levels for species protection.