Endangered Species Law & Policy

On March 10, 2010, the Center for Biological Diversity submitted a letter (PDF) on behalf of 50 conservation groups encouraging the Secretaries of the Department of the Interior and the Department of Commerce to adopt a radical new definition of adverse modification of critical habitat.  The proposed definition differs in two ways from the current regulatory definition; one uncontroversial and benign, while the other is likely to be controversial and far-reaching.

Currently, adverse modification is defined by regulation as a direct or indirect alteration that appreciably diminishes the value of critical habitat for both the survival and recovery of a listed species.  The groups would have adverse modification of critical habitat be defined as a direct or indirect alteration that appreciably diminishes the value of any portion of any area of designated critical habitat for either the survival or recovery of a listed species, with appreciably diminishes defined as any action that would destroy or degrade any primary constituent element such that the habitat would be, measurably or perceptibly, of less value to the species.  As explained below, the change to either . . . or would be benign; but the proposed addition of any portion of any area could dramatically alter the way the Services administer Section 7 of the ESA.