A new study from researchers at the University of Florida confirms the capture of three Nile crocodiles near Miami, raising the concern that a population of the man-eating reptiles could rise in the United States. As of now, experts are still trying to figure out how they ended up in Florida.
"They didn't swim from Africa," said Kenneth Krysko of the University of Florida and co-author of the paper. "But we really don't know how they got into the wild."
Krysko and his team used DNA testing to determine that three animals captured in 2009, 2011 and 2013 are Nile crocodiles, a terrifying species whose males grow to more than 16 feet long and more than 1,600 pounds. They are believed to be responsible for 200 deaths per year in sub-Saharan Africa, a figure that makes the annual average of six shark attacks look tame by comparison.
The data reveals that although the captured crocodiles are genetically related, they don't match up with the Nile crocodiles kept at Disney's Animal Kingdom and other Florida animal attractions, meaning they were likely brought to the state illegally for pet trade.
"My hope as a biologist is that the introduction of Nile crocodiles in Florida opens everyone's eyes to the problem of invasive species that we have here in our state," Krysko said. "Now here's another one, but this time it isn't just a tiny house gecko from Africa."
If the man-eating Nile crocodile ever becomes established in the Everglades, the University of Florida team warns that it will pose an invasive threat to the ecosystem through crossbreeding, pushing out the less aggressive American crocodiles. Furthermore, any hybrids would hurt the genetic integrity of the American variety, which are currently endangered.
Nile crocodiles don't reproduce rapidly, so we don't have to get too worried yet, but experts say all it would take is the successful breeding of one male and one female to kickstart the reproductive process and lead to an Everglades population.
"I have two words: Burmese python," said Joe Wasilewski, an independent wildlife biologist and co-author of the study. "If you would have told me 15 years ago we would have an established population in the Everglades, I wouldn't have believed you."
The findings were published April 30 in the journal Herpetological Conservation and Biology.
