In the case of Palila v. Hawaii Department of Land and Natural Resources (639 F.2d 495 (9th Cir. 1981)), HDLNR had introduced wild sheep and goats to an area to promote sport hunting.  However, the sheep and goats were damaging a species of tree that was important to the endangered Palila bird.  The Court found that, pursuant to the Endangered Species Act §9, the introduction of the sheep and goats constituted a 'taking' of the endangered species, and was therefore not allowed. In response to this decision, the Department of the Interior (DOI) sought to modify the definition of a 'taking' to include only those actions which actually kill or injure wildlife. After the invasive species of sheep and goats were removed, HDLNR tried to maintain a native species of wild sheep for hunting.  This led to Palila v. Hawaii Department of Land and Natural Resources (852 F.2d 1106 (9th Cir. 1988)), in which the could held that a finding of 'harm' did not require a showing of death to an individual member of the species, but rather only an "adverse impact on the protected species." Basically, under this decision any habitat destruction that could lead to the extinction of a species is considered a harm, and is therefore unallowable under ESA §9. Btw, these suits were brought by the Sierra Club and Hawaii Audubon Society, but they listed the plaintiff as the Palila bird.  It was the first time in American legal history that a non-human was a listed plaintiff in a court case.