July 11, 2004
BY JENNIFER BABSON
GRASSY KEY - It's the kind of thing you don't really want to brag about to the visiting in-laws.
Clowny-looking rats the size of small house cats. Breeding more than rabbits.
Nope, it's not "News of the Weird.''
Researchers and residents on this roughly three-mile stretch just northeast of Marathon are trying to get a handle on a population explosion of Gambian giant pouched rats that has even state health officials paying attention.
Legions of the non-native rats -- which have been known to balloon to as big as nine pounds -- have burrowed in on Grassy Key. Locals say they are descendants of a few who managed to escape several years ago from the confines of an exotic animal breeder who's since left town.
The critters are the kings of the rat family, with a taste for peanut butter and a funny gait that makes them look prehistoric. They collect food -- which they bury in the ground -- inside their cheeks, live up to eight years in captivity and can be docile if domesticated.
The animals have a sense of smell so uncanny that they have been studied for use in detecting tuberculosis and in sniffing out land mines.
Even that might have a downside, though.
''You can imagine that the countermeasure the enemy would use would be cats,'' said Cmdr. Christopher L. Butler, a London-based analyst with the Office of Naval Research who has reviewed the rats for use in buried mine detection.
Now scientists wonder if these long-tailed mammals can be contained in the Keys.
''It might be too late already,'' said Neil Perry, a Texas A&M University biologist who is trying to determine just how many of the nocturnal creatures roam here. No one is sure how many rats there are, but an increase in sightings lately -- mostly in backyards and around heavy brush -- has drawn the attention of researchers.
''The worst case scenario is they thrive and they spread throughout the Keys,'' Perry said.
That possibility concerns state and federal biologists charged with protecting a host of endangered species -- from the Key Largo wood rat to a number of rare birds -- that could be at risk if the rodents keep reproducing.
And there's also a possible health concern: The Gambian rat has been known to carry monkeypox, a rare viral disease that generally manifests in humans like a less severe, much less infectious form of smallpox. The Centers for Disease Control and Prevention and the Food and Drug Administration banned importation of the rats last year after virus-carrying rodents from a particular shipment prompted the first reported outbreak of monkeypox in the U.S.
TARDY PRECAUTION
As a precaution, the agencies also prohibited the rat's ''release into the environment.'' It was too late for the Keys.
While the Florida Department of Health ''hasn't received any complaints or concerns'' about the rats, a spokeswoman said Friday that the state is ''monitoring the situation'' and plans to soon test the Keys rats for monkeypox, though there is no reason now to suspect they are carrying the virus.
''It's worth noting that in any situation like this, we always urge individuals to not pet and not come in contact with unknown animals,'' spokeswoman Lindsay Hodges said.
Hoping to obtain a better estimate of their number -- which some locals are convinced is at least into the hundreds -- Perry plans to inaugurate a Gambian rat trapping project next month.
It won't be hard to find them.
'Every once in a while, you will see one go by and say, `Oh gosh, was that a rat?' '' said Karen Bass, who has seen them in her Grassy Key neighborhood for a few years now.
The critters are just the latest non-native ''exotic'' species to be introduced into the wilds of South Florida. Burmese pythons now slither through the Everglades, while Madagascar geckos dart around the Keys.
But rats have particularly keen survival skills, says Winston Hobgood, a U.S. Fish & Wildlife Service biologist who is working with Perry.
''Rats are well known for coming up with ingenious ways to end up in new places,'' Hobgood said. ``All it's going to take is one to get into the undercarriage of a car or a truck and go get dropped off in Key Largo or Miami.''
``Who knows, they may end up in the Everglades next.''
Connie Faast, a Grassy Key resident who has trapped one rat and seen others scurrying at night under her stilt house, knows how adaptable the critters are.
She even watched a couple of the massive rodents duke it out recently on hind legs in plain sight.
''They looked like they were boxing, like kangaroos,'' she said. ``Their mouths were open but I didn't actually see them bite one another.''
FEEDING FRENZY
Faast suspects the rats -- who will eat anything from fruits and bird nests to garbage -- are mooching for their dinner.
``In Grassy Key, people put food out for the wild cats and such and I'm sure that the rats are enjoying their free meals.''
Faast says she's not interested in adopting any as pets, even though rat aficionados contend the Gambian giant pouched rat makes a loveable companion.
Said Faast: ``They are creepy looking; they are dirty looking. I don't particularly want them in my neighborhood.''
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