Habitat loss and degradation are the leading causes of species endangerment in North America. Increasingly, climate change is becoming a significant factor in species endangerment as it disrupts migration routes, changes animal
behavior, and shifts species’ ranges. In the coming decades, habitat loss and climate change will threaten more than one million species. To prevent future extinctions, governments need to be flexible in responding to threats species face and proactive in protecting current and potential future habitat.
Unfortunately, in Weyerhaeuser v. U.S. Fish and Wildlife Service, the Supreme Court missed an opportunity to interpret existing law as granting the United States Fish and Wildlife Service (the Service) this flexibility. Weyerhaeuser was about whether the Service could designate land as critical habitat under the Endangered Species Act (ESA) even though the endangered species at issue, the dusky gopher frog, did not currently live there and could not live there without “reasonable” modifications to the land. The Court held that critical habitat must be “habitat,” but it failed to define what constitutes habitat. If habitat is defined narrowly, the results could be catastrophic; restricting the Service’s ability to protect land for species reintroduction. However, the text, purpose, and history of the ESA all support a broad definition of habitat: one that includes areas that might require some modification to support a sustainable population. This In Brief first describes the ESA, then discusses the Court’s holding in Weyerhaeuser, and finally argues that habitat should be defined broadly.