the U.S. Endangered Species Act USF&WS website Endangered Species ESA Endangered Species Act Endangered Species Act 43-year-old law Endangered Species the U.S. Endangered Species Act the U.S. Endangered Species Act Endangered Species Act first prong of the ESA in 1966 Endangered Species federal government began keeping an official list The Endangered Species Preservation Act of 1966 A History of the Endangered Species Act of 1973 USF&WS Endangered Species Act ESA Basics: 40 Years of Conserving Endangered Species Endangered Species Act federal government began keeping an official list Jaguars were officially classified Jaguars were officially classified Endangered Species Act Endangered Species Act 1973 ushered in another amendment federal government began keeping an official list federal government began keeping an official list Endangered Species Act