In this Oct. 20, 2015 photo, illegally trafficked leopard and tiger heads stored by the U.S. Fish and Wildlife Service’s Office of Law Enforcement fill the shelves of a warehouse inside the National Wildlife Property Repository in Commerce City, Colo. More than 1.5 million items fill the shelves of the warehouse on a wildlife refuge just northeast of Denver. A one-of-its-kind repository, it’s the only place in the United States that stores such a large collection of wildlife items seized by law enforcement, offering a macabre look at the cost of the global trafficking of endangered and threatened animals. (AP Photo/Brennan Linsley)