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. 3–15.


This book examines one legislative effoft to resolve the dilemma, the Endangered Speeies Aet of 1973 (ESA 1973). The ESA was an idealistic and perhaps naive attempt to preserve humanity by preserving other species in the ecological support system that makes life possible. In the words of the House report accompanying the bill:

A certain humility, and a sense of urgency seem indicated .... One might analogize the case to one in which one copy of all the books ever printed were gathered together in one huge building. The position in which we find ourselves today is that of custodians of this building, and our choice is between exercising our responsibilities and ignoring them. If these theoretical custodians were to permit a madman to enter, build a bonfire and throw in at random any volume he selected, one might with justification suggest that others be found, or at least that they be censored and told to be more careful in the future. So it is with mankind. Like it or not, we are our brothers' keepers, and we are also keepers of the rest of the house. (U.S. Congress 1973,4-5)

Species conservation was already a difficult challenge in 1973. The human population of the United States had inereased from less than 4 million in the first census of 1790 to roughly 212 million by 1973 (Census Bureau 2000). This increase was accompanied by even more dramatic increases in per capita consumption of resources. The combination of population growth and increased consumption has driven a precipitous loss of nonhuman species that continues today: more than five hundred species formerly found in the United States are presumed to be extinct and an additional 47 percent of the species unique to this country are at risk (Master et al. 2000).