this. The Mexican duck was listed as endangered species at the United States Fish and Wildlife Service in 1967 but was removed in 1978. References American Ornithologists' Union (AOU) (1983): Check-list of North American Birds (6th edition). American Ornithologists' Union, Washington, DC. Madge, Steve & Burn, Hilary (1987): Wildfowl : an identification guide to the ducks, geese and swans of the world. Christopher Helm, London. McCracken, Kevin G.; Johnson, William P. & Sheldon, Frederick H. (2001): Molecular population genetics, phylogeography, and conservation biology of the mottled duck (Anas fulvigula). Conservation Genetics 2(2): 87–102. PDF fulltext Rhymer, Judith M. (2006): Extinction by hybridization and introgression in anatine ducks. Acta Zoologica Sinica 52(Supplement): 583–585. PDF fulltext Rhymer, Judith M. & Simberloff, Daniel (1996): Extinction by hybridization and introgression. Annu. Rev. Ecol. Syst. 27: 83-109. (HTML abstract) Footnotes Anas Ducks Birds of Mexico Least concern biota of Mexico Least concern biota of North America Birds described in 1886 Taxa named by Robert Ridgway nah:Xomōtl