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Dusky seaside sparrow
The dusky seaside sparrow, ''Ammodramus maritimus nigrescens'', was a non-migratory subspecies of the seaside sparrow, found in Florida in the natural salt marshes of Merritt Island and along the St. Johns River. The last definite known individual died on June 17, 1987,〔''Newsweek'', June 9, 2008 page 45〕 and the subspecies was officially declared extinct in December 1990.
== Origin ==
The dusky seaside sparrow was first categorized as a species in 1873. Its dark coloration and distinct song are what separates it as a subspecies of other seaside sparrows. Found in the marshes of Florida's Atlantic Coast on Merrit Island and the upper St. Johns River, the dusky seaside sparrow was geologically isolated from other seaside sparrows (Hill 239). it was categorized as a subspecies in 1973. Even though the dusky's mitochondrial DNA is the same as the mitochondrial DNA of other seaside sparrow populations, DNA testing by itself doesn't demonstrate that its subspecies classification is undeserving (Hill 239). In 1981, only five dusky seaside sparrows remained, all being males. Conservation efforts were made by trying to breed the remaining duskies with Scott's seaside sparrows in order to create half dusky hybrid offspring. "Unfortunately, although the Fish and Wildlife Service initially supported the crossbreeding program, it withdrew its support due to Interior's hybrid policy" (Hill 239). Due to only the males being left, even though duskies could be crossbred with other seaside sparrows, there would never be another pure dusky seaside sparrow again.〔(The Endangered Species Act: What Do We Mean by Species? ), from the ''Boston College Environmental Affairs Law Review'', volume 20, issue 2, article 3; by Kevin D. Hill; published 1993; retrieved October 26, 2012〕
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