Florida Crocs Make A Comeback

by Kate Furey DVM

Conservation efforts in the swamps of South Florida have proven so successful for the American crocodile, the U.S. Fish and Wildlife Service is considering down-listing the species’ classification from endangered to threatened.

The reptile, whose territory extends from its northernmost home of South Florida to Peru, earned its endangered species status from both U.S. and international agencies when hunting and habitat losses caused its population to plummet to less than 400 individuals just three decades ago.

Hunting restrictions and habitat reclamation have helped replenish the dwindling population to 1000.

University of Florida ecologists Frank Mazzotti and Mike Cherkiss are in year 26 of the longest-running research project/census ever devoted to the American crocodile - a labor intensive venture involving capturing, measuring and tagging the creatures, and returning them to the swamp.

Identification of each animal is made by removing scales, or "scutes", from each reptile’s back in a unique, prescribed sequence. Data entered into a "croc catalogue" are used to track the species’ population growth and survival rates.

"I study crocodiles because they’re endangered and ecologically important, and because they’re the last of the dinosaurs. They’re really our only chance to understand how that group...was able to survive," Mazzoti said.

Crocodiles make their habitat along Florida’s coastal estuaries where salt and fresh water mix and where mangrove swamps offer protection from wind and waves.

"The (species’) recovery has a lot to do with the restoration of the Everglades," explained Mazzoti.

The natural water flow establishes an ideal ratio of salt to fresh water in which young crocodiles thrive, whereas excessive saline content can prove life-threatening.

Despite documented species reinvigoration, "The crocs aren’t out of the woods yet," asserts John Thorbjararson, a zoologist with the Wildlife Conservation Society of the Bronx, and an authority on the world’s 23 crocodile species.

The American crocodile (Crocodylus acutus) can be distinguished from the alligator by its lighter color and longer, narrower snout. The crocodile’s teeth are visible even when its mouth is closed.

The American croc is also much shyer than the alligator, and certainly shyer and less aggressive than its cousins, the Nile and Australian crocodiles.

While legal constraints on hunting crocodiles affords them some protection, habitat encroachment, especially displacement of nesting sites, bids them constant peril; females killed by cars en route to nesting grounds represent most fatalities.

Even as great strides toward population recovery are being made, "human intolerance will keep the crocs endangered," said Mazzoti. "This is a success story still in progress."

© 2003 Animal News Center, Inc.