KEY LARGO -- "Never smile at a crocodile" has taken on a more sinister meaning for families whose homes border a canal where a dog was killed last month by one of the federally protected reptiles.

With the resurgence of the normally shy North American crocodile from the brink of extinction 37 years ago, the number of nuisance complaints received by the Florida Fish and Wildlife Conservation Commission has steadily increased. In Monroe County, complaints more than doubled between 2008 and 2011, jumping from 22 to 49.

Now residents of the Twin Lakes canalfront neighborhood, where a 65-pound Labrador retriever named Roxie was snatched from a dock by a 10-foot crocodile last month, are keeping their children and pets away from the water's edge.

Several neighborhood residents witnessed the drama unfold after the reptile attacked the pet prompting a Florida Fish and Wildlife officer and a neighbor to retrieve the dog's body.

"[One of the crocodiles] jumped out of the canal in Twin Lakes and took a dog," wrote Shaw Drive resident Marilyn Beyer in an email the day after the attack. "I know they are [protected] but they are no longer afraid of people."

Although there has never been a documented case of an American crocodile killing a human, Beyer and others are rethinking their canal-side activities.

"We're not going to be fishing in the canal any more," Beyer told the Free Press last week. "We won't be standing on the floating dock any more with small nets catching crabs and tiny fish. It is only a foot out of the water."

Beyer, who lives near where Roxie was attacked, says three crocodiles frequent her canal.

Julie Erickson, Beyer's neighbor and a mother of five children, ages 11 through 19, says she used to let her children swim in the canal, especially when they had a special event such as a birthday party.

"I won't let my kids in the canal any more. It really creeped me out when they pulled the dog into the boat across the canal from us," she said. "I don't let the youngest ones catch minnows from the dock any more. We've had crocs sun themselves on the boat ramp."

Carlos Machado, who lives with his family nearby, says they haven't been in the canal since their 12-year-old lab suddenly disappeared two years ago.

"Four days after she went missing, a neighbor called us saying they found Missy," Machado recalls. "They found her in the canal and half of her was missing. Her bottom half was gone and we identified her by her collar. It was very sad."

Machado said he wasn't sure if the dog had drowned and later been eaten by a crocodile, or had been taken by one of the reptiles.

Either way, his friend, Mario Brand, says Machado has been reluctant to take any of his three dogs near the canal ever since.

"Especially at night, I stay away from the water," Machado confided. "Since this most recent incident, I'm even more cautious around the docks."

Growing numbers

Since the reptiles were placed on the federally endangered list in 1975, when just 200 of them were thought to exist in South Florida, their numbers have grown to around 2,000. In 2007, the United States Fish & Wildlife Service declassified the American crocodile as an endangered species, downgrading its status to "threatened," which still protects the reptile from illegal harassing, poaching or killing

As the reptile's population has grown, the number of complaints about crocodiles frequenting populated areas has increased, according to information compiled by biologist Lindsey Hord, FWC crocodile response coordinator.

The list documented 22 complaints in Monroe County in 2008; 32 in 2009; 48 in 2010; and 49 in 2011. Through the end of March of this year, FWC has fielded 13 complaints.

Possibly more telling is the steady rise in what FWC refers to as "handling events," which is when FWC has to "physically handle" a crocodile, either to relocate a live reptile or to recover a carcass, said Hord.

No handling events were reported in Monroe County in 2005. Two each year occurred from 2006 through 2008. In 2009, there were three; in 2010, six; and 2011, eight.

"Captured crocodiles are either released near the capture site, translocated or removed from the wild," Hord stated.

FWC spokesman Bobby Dube said officers are still trying to locate the crocodile involved in the Twin Lakes incident.

"We are continuing to search for the croc that killed the dog," he said last Friday. "We have neighbors monitoring the canal. If they spot it, we will call the trapper down from Miami-Dade County. We will relocate the croc but we will never euthanize one. If, heaven forbid, a human is ever attacked that would change the entire game plan."

Crocodile expert Frank Mazzotti, professor of wildlife ecology at the University of Florida, says the likelihood of such an attack is remote. The North American crocodile, unlike some of its more fearsome cousins, is not considered an aggressive species and there are no officially recorded instances of the American crocodile attacking a human.

Though a large American crocodile would be strong enough to take a small child, it "is not likely," Mazzotti said.

Steve Klett, formerly the manager of the Crocodile Lake National Wildlife Refuge, about three nautical miles from the Twin Lakes neighborhood, told the Free Press that there are about 150 adult crocodiles that live in the refuge and they are the healthiest of those that inhabit the three main nesting areas in South Florida. The other nesting areas include Everglades National Park and the area around Turkey Point in south Biscayne Bay.

Given the reptile's rebound, encounters between humans and crocodiles are likely to continue. So Dube advises people to avoid initiating any contact.

"Watch them from afar and educate your kids," he said. "Once it loses its fear of humans it can quickly become a nuisance. Also don't leave anything around that would attract them. At fish cleaning stations bag the scraps rather than tossing them into the canal. Don't feed them and don't get close to them."

sgibbs@keysnews.com