2500 - 10,000 individuals
Comments: Total adult population size is unknown but is at least a few thousand and probably is less than 10,000.
The best, current, minimum population estimate of the statewide Florida manatee population is approximately 3,300 animals, based on a single statewide count at warm-water refuges and adjacent areas in January 2001 (USFWS 2007); although surveys have been conducted more recently than 2001, the weather conditions for that particular survey were ideal and, as a result, the count from that year still provides the best minimum population estimate (USFWS 2007). However, the 2001 count is now several years old, and given ongoing mortality (see threats) the current manatee population in Florida may no longer be 3,300.
A January 2005 helicopter survey of the entire Puerto Rico coast yielded a count of 121 manatees, including 20 calves (Mignucci-Giannoni 2005). Mignucci-Giannoni (2005) speculated that the relative abundance of manatees in Puerto Rico may be between 150 and 360 individuals.
Numbers are undocumented elsewhere.