The Amazonian manatee is classified as Vulnerable by the IUCN, a consequence of centuries of hunting after the European discovery of the Amazon, along with modern day local hunting, trade, and entanglement with fishing gear. (Six out of the ten radio-tagged manatees studied were hunted by local communities over the course of the research.) Dams can exacerbate these threats, as the human population — and therefore the demand for meat — increases during and after dam construction.
Yes - the Amazon has manatees!