WASHINGTON, Sept. 13 (UPI) -- DNA of manatees in Belize shows they are a separate subspecies from their Florida counterparts but are threatened by low genetic diversity, researchers say.
Belize has the largest known breeding population of Antillean manatees that scientists had hoped could repopulate other parts of Central American where manatees are severely reduced or threatened, a U.S. Geological Survey release said Monday.
But the low genetic diversity worries researchers.
"It turns out that the genetic diversity of Belize's manatees is lower than some of the classic examples of critically low diversity," USGS conservation geneticist Margaret Hunter, who led the DNA study, said.
When a population drops to low numbers, researchers say, the diversity of its gene pool also shrinks. Even if it rebounds to greater numbers, that population decline leaves a legacy of reduced genetic diversity known as a bottleneck.
This renders the population more vulnerable to threats to their survival such as disease, hurricanes or habitat destruction, scientists say.
The low genetic diversity in Central American manatees is blamed in part on centuries of hunting that were only curtailed early in the 20th century.