he designation of critical habitat under the Endangered Species Act (ESA) can result in significant and costly consequences for landowners, industry, government, and other entities—often with little if any evidence of a commensurate benefit to the species involved. In Critical Habitat and the Challenge of Regulating Small Harms, Professor Dave Owen provides a valuable contribution to assessing the role of critical habitat during  consultation on federal agency actions under ESA section 7.1 

Specifically, in reviewing and analyzing over 4,000 biological opinions, Professor Owen devotes substantial time and resources to developing a better understanding of critical habitat in formal consultation between agencies undertaking federal actions, such as issuing permits or rules or providing project funding, and the U.S. Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) (together, the Services). Although his analysis is limited to information contained in the Services’ biological opinions, Professor Owen provides valuable, hard data showing the on-the-ground impacts of critical habitat on the consultation process, which is useful for understanding and weighing policy choices associated with critical habitat designation. Finding that the Services construe the ESA prohibition against adverse modification of critical habitat to exclude “minor alterations” of habitat, Professor Owen concludes that the ESA’s prohibition of “adverse modification” of critical habitat thus has little effect upon the consultation process.

In order to understand the full impacts and costs of critical habitat designation, however, it is necessary to view critical habitat from a wider perspective that considers the effect of critical habitat designation outside of the formal ESA section 7 consultation process.