Since observing what was called a "Mexican Black Duck" in July 31 in Mineral County, I continue to attempt to trace the history of the confusing nomenclature of this bird, as time permits. Here are a few items that I have stumbled across:
Year 1893 - first "Mexican ducks" collected in US and preserved at Smithsonian Institution, but these were "actually genetic hybrids although they looked like pure Mexican ducks," according to the Dept. of Interior, F&WS, July 26, 1978, when "Mexican Duck" was removed from endangered list. The same news release said that they were hybrids of "true Mexican ducks" and "common mallard" and were expanding their range in 1973.
Year 1921 - in essay in The Condor (Jan.-Feb. 1921), Aldo Leopold reported weights of ducks in Rio Grande Valley between Albuquerque and Socorro, NM, and
included 101 "Mallard" and 12 "Black Mallard." [This article caught my attention while reading about Leopold)
Year 1973 - Peterson, Field Guide to Mexican Birds lists Mallard (Anas platyrhynchos), Mexican Duck (Anas diazi), Mottled Duck (Ana fulvigula).
Year 1998 - Peterson, Field Guide to the Birds of Texas lists Mallard (A. platyrhynchos); Mexican Duck (A. diazi); Black Duck (A. rupripes - [note that this is the scientific name for American Black Duck of SE US]), and calls it "Black Mallard" in parentheses; and Mottled Duck (Anas fulvigula).
Year 2001 - Cornell Lab and AOU says that Mottled Duck and Mexican Duck are each other's closes relatives and in turn are closed related to American Black Duck.
AOU, 7th ed. lists American Black Duck, Mallard, and Mottled Duck but no Black Duck, Black Mallard, or Mexican Duck.
For more on present thought, see the references in my earlier e-mail (antional Georgraphic Complete Birds of North American, and the Webster article, The Status of Mottled Duck (Anas fulvigula) in Arizona.
On and on into the brave new world....
Virginia Simmons, Del Norte