Cumulative Effects and Optimal Targeting of Conservation Efforts: Steelhead Trout Habitat Enhancement in Oregon

A major problem with some conservation programs is that they ignore potential cumulative (threshold) effects in environmental quality management. The objective of this study is to investigate the importance of cumulative effects in the targeting of conservation efforts. The empirical focus is on habitat investments to protect an important anadromous fish species in the Pacific Northwest, steelhead trout. Results of the analysis point to a substantial cumulative effect in the relationship between water quality and abundance in this fishery, which affects the efficiency of specific habitat investments.