The United States Court of Appeals for the Tenth Circuit recently affirmed a lower court decision that the U.S. Army Corps of Engineers need not consult with the U.S. Fish and Wildlife Service under section 7 of the Endangered Species Act regarding the operation of dams and other facilities on the Rio Grande River.  The dispositive issue in the case was whether the Corps has discretion to act such that it is obliged to engage in consultation regarding the effects of its operation of the Middle Rio Grande Conservancy Project on the endangered Rio Grande silvery minnow and southwestern willow flycatcher.

To determine whether the Corps had discretion to consult regarding the effects of its actions on the silvery minnow, the Tenth Circuit reviewed the legislation that authorized the Project -- the Flood Control Acts of 1948 and 1960.  Upon review of the legislation, the court held that neither Act provides agency discretion.  In reaching its decision, the Tenth Circuit was guided by the Supreme Court's analysis in National Association of Homebuilders v. Defenders of Wildlife, 551 U.S. 644 (2007). The decision reinforces the fact that the determinant of whether a federal agency has discretion to consider impacts of its activities on listed species is the federal law authorizing such activities.