U.S. Federal Endangered and Threatened Species by Calendar Year

This report counts all U.S. species listed as threatened or endangered under the Endangered Species Act of 1973 (with amendments) and its precursors (Endangered Species Preservation Act of 1966 and Endangered Species Conservation Act of 1969). The count for each year is the number of species added to the list in that year. The status of a species may change after it is listed, either from threatened to endangered or from endangered to threatened; however, this report counts only the date of the first listing. Furthermore, a species may have subsequently been delisted. Therefore, if the number of species listed each calendar year is added up, that total will be different than the total number of species currently listed under the Endangered Species Act. Experimental populations, and foreign species are not included. Distinct population segments (DPS) are included, as are species listed due to similarity of appearance and joint U.S./foreign listings (those that are listed in the U.S. and an adjacent country). The effective date (as given in the Federal Register notice) is used to determine in which Calendar Year a species is counted.