CORAL GABLES, Fla. — Three dead dogs, and Chris Marin has had it.

He’s lived with his family along a canal just south of Miami for several years, and never had a fear of the water — until now.

“When we first moved in, I even put a swing on a tree here for my kids to plunge into the canal,” Marin said.

Then the poodles began to vanish from his backyard — first Spotty, then Luna and Angel.

The culprit? In much of Florida, the suspect would be an alligator. In this case, it’s an 11-foot American crocodile.

Marin, 49, said living on the water just isn’t worth it anymore. He’s packing up and moving.

“You barely get to enjoy the backyard,” he said. “My kids won’t even step out here.”

Listed as a federally endangered species in 1975, after hunting and habitat loss nearly wiped it from the wild, the American crocodile has surged to numbers not seen in a century. Today, the population is about 2,000 at the southern tip of Florida, the species’ only U.S. habitat, where the U.S. Fish and Wildlife Service has downgraded its status to threatened.

As it returns to its historical range — now populated by millions of humans — the American crocodile, which can grow to 15 feet, will be living more in people’s backyards, especially those closest to the coast.

“We’re seeing crocs in places they haven’t been seen in decades,” said Lindsey Hord, a biologist with the Florida Fish and Wildlife Conservation Commission.

It’s alarming to some residents, even in a state that already has more than a million alligators. Florida wildlife officials get thousands of complaints every year from residents fearful of gators, which can eat dogs, cats, and, very infrequently, people. About 140,000 problem alligators were killed in Florida between 1977 and 2007.

American crocodiles have never made a documented attack on a human in the U.S. Here, it’s domestic pets that more often become crocodile food.

“Crocodiles don’t see much distinction between some small mammal that they have naturally eaten, like a rabbit, and somebody’s dog,” Hord said.

Alligators can be found in any freshwater body throughout the state, likely part of the reason for so many attacks on humans — at least 312 unprovoked ones in Florida since 1948, 22 of them fatal — but crocodiles are confined to South Florida.

They need warmer temperatures, and live where salt and fresh water mix. Florida is the only place in the world where alligators and crocodiles coexist.

Crocodiles are distinguished from gators by their lighter color, narrower snout and an exposed fourth tooth on their lower jaw. While they haven’t attacked people in this country, American crocs have gone after people in parts of Mexico, Central and South America and the Caribbean.

Hord noted that human complaints are rising along with the American crocs’ numbers, which he said likely will continue to increase.

Several developments have aided the crocodile’s recovery, including habitat protection and some places not specifically set aside for the species. The animal has found an unlikely home on the grounds of Florida Power &Light’s Turkey Point nuclear plant about 30 miles south of Miami, a sort of replacement habitat for land lost to development in Miami Beach and Key Biscayne.

The remoteness of the site, which is closed to the public, has given the crocodile room to breed. They’ve reproduced so successfully that now they’re venturing out to populated areas.

Some are ending up in neighborhoods close to the coast, which crocs consider prime habitat, while alligators prefer more fresh water found inland. Christine Esco, who lives down the street from Marin, has a crocodile in her backyard canal that’s become so well known he’s even got a name: Pancho. It’s the same croc authorities suspect ate Marin’s dogs.

The 11-footer has been relocated twice to more remote areas, and twice he’s returned, typical behavior for the species.

Unlike the crocodile, whose protected status means it can only be relocated or put into captivity, problem alligators typically end up as meat and hide when they have to be removed because of safety concerns.

As for Pancho, the next time he is caught, he’ll go to a zoo. Crocodiles only get two chances. The third time they return, they are put in captivity.

“It’s very unnerving and scary,” Esco said. “I have two small children … Pancho, in my opinion, is a time bomb.”

Wildlife officials say residents simply need to take precautions: No swimming in crocodile waters between dusk and dawn, when they feed; supervise children near canals, and keep your pets well away from the water’s edge.

American crocodiles are generally less aggressive and more shy than alligators, and “the truth is you’re more likely to drown than be attacked by an alligator or a crocodile,” said University of Florida professor Frank Mazzotti, who has studied crocodiles for more than 30 years. “That said, don’t be stupid.”

Mazzotti said the American crocodile’s recovery in Florida “is a real endangered species success story.”

“The Endangered Species Act comes under a lot of attacks,” Mazzotti said. “Here is just an absolutely stunning example of the fact that it works.”

The crocodile’s future here depends at least in part on people’s willingness to adjust their behavior to live with the creature, Mazzotti said.

“Wildlife management,” he said, “is really people management.”