Date of this Version
The 1970s was a decade of increased awareness of environmental problems, and emphasis was placed on the development of procedures for predicting impacts of proposed developmental activities on natural systems. Impact assessment has evolved from a focus on species numbers, human use, species richness, and related methods to include the investigation of habitat as a supplemental or alternative approach to environmental planning, mitigation, species management, and impact assessment (Schamberger 1979, U.S. Fish and Wildlife Service 1980a, 1980b). The impetus for habitat-based assessment techniques came primarily from two sources: (1) environmental legislation requiring noneconomic project evaluations; and (2) an awareness within the scientific community that traditional methods of inventory and analysis were inadequate for land and water planning purposes. Baseline studies of the early 1970s typically resorted to inventories of existing plant and animal species. Such inventories were time consuming, documented only existing conditions, and did not provide a framework appropriate for predicting and evaluating future conditions. In addition, Federal land management agencies generally focus on habitat, not species, management (e.g., Crawford and Lewis 1978). Thus, a documented need exists for a habitat approach to impact assessment. The U.S. Fish and Wildlife Service (FWS), in cooperation with the U.S. Soil Conservation Service (SCS), U.S. Army Corps of Engineers (COE), U.S. Bureau of Reclamation (BR), and State and private organizations developed a standardized, habitat-based evaluation technique to meet this need.