American crocodiles are spreading north in Florida. That’s a good thing. (2024)

On a canal bank lined with palm trees off the Banana River in Satellite Beach, Florida, in October,a 10-foot-long American crocodile basked in the midday sun, its toothy jaws opening as neighbors looked on from their docks.

The reptile had become the subject of gossip and local news, because until this year, most residents in the coastal communities east of Orlando had never seen one, according to the Florida Fish and Wildlife Conservation Commission. Some were frightened. More were curious. Nonetheless, the commission decided it was in everyone’s best interest to intervene. State trappers wrangled the male crocodile, taped his jaws shut, and loaded him into a transport vehicle bound for southern Florida, where he was released.

American crocodiles typically live in the mangrove estuaries in and around the Everglades—a good 200 miles from Banana River. Although the historic range of American crocodiles reaches up Florida’s coasts as far as the Canaveral National Seashore, northeast of Orlando, massive habitat loss had virtually eliminated the species from the north.

But over the past few years, verified sightings of American crocodiles north of the Everglades have climbed, and experts believe the reptiles may be reclaiming at least some of their homeland. Though no one knows how many crocodiles live in northern Florida, the increase in sightings suggest the animals will begin breeding soon, experts say.

Florida is the only place in the world where alligators and crocodiles coexist in the wild. American crocodiles reach about 15 feet in length, while the average American alligator seldom exceeds 10 feet. The best way to tell the species apart is by the shape of their snouts: Alligators have a rounder appearance, while crocodiles’ noses narrow to a point.

Like their smaller alligator cousins, the American crocodile was declared endangered in the 1970s by the U.S. Fish and Wildlife Service. Thanks to mangrove forest conservation, their numbers have risen dramatically from an estimated all-time low of around 150 to around 2,000 individuals in the state of Florida. While the International Union for Conservation of Nature lists the American crocodile as vulnerable overall, the FWS downlisted the species—in Florida only—to threatened in 2007. (Read: Can restoring mangroves protect Miami from rising seas?)

“It’s an endangered species success story,” says Frank Mazzotti, an ecology professor and American crocodile expert at the University of Florida. The species’ return is positive, especially because the apex predators are vital to the coastal wetlands, helping keep prey animals in check, he says.

They’re also not a threat to people. “Due to the American crocodile’s shy and reclusive nature, conflicts between them and people are extremely rare in Florida, with only one [non-fatal] bite incident ever having been documented,” says Lauren Claerbout, a spokesperson for the state wildlife commission.

More mangroves, more crocs

Just like American alligators, American crocodile populations in Florida took a downturn largely due to habitat destruction. Roads and dikes staunched and diverted the Everglades’ natural southward flow, rendering many downstream habitats inhospitable. These habitat changes have posed a bigger problem for crocodiles than for their hardier relatives.

While alligators have made themselves at home in just about any water body in Florida, including swimming pools, crocodiles are not as flexible, and need mangrove forests to thrive. Though once the dominant coastal habitat in southern Florida, many mangrove forests have been destroyed by construction and hurricane activity supercharged by climate change.Many Floridian coastal estuaries have lost as much as 60 percent of their mangrove forest cover in the past century.

For instance, Everglades National Park and Florida Bay, to the park’s south, still experience disrupted flows, which is why crocodiles are scarce there, according to data collected by CrocDocs, a multidisciplinary team at the University of Florida.

Instead, their data indicates that the reptiles are flourishing in habitats outside the Everglades region, such as protected areas around Biscayne Bay south of Miami and Crocodile Lake National Wildlife Refuge on Key Largo. They’re doing so well, in fact, that the animals are setting off for new territories. (Learn how American crocodiles can have “virgin births.”)

“It’s the same thing as with the human population,” says Mazzotti. “When you have a healthy population of animals, they have to find more areas to occupy, and these crocodiles are moving up the coast in response to that.”

A large-scale effort to safeguard mangrove wetlands, particularly as state and federal protected areas, has boosted the species’ numbers. In 1996, Florida enacted a law that bans “direct human damage” to mangroves, and various state agencies and volunteer organizations have replanted mangrove forests over the years.

Florida’s alligator population, which is widespread across the state, has also benefited from such initiatives. In recent decades, the reptile’s population has skyrocketed past a million, hurdling from peril straight into the status of nuisance animal that often shares space with human neighbors. Even so, alligators bite an average ofeight people a year, making them far less dangerous than bees, according to the state commission. State-licensed trappers like the ones who nabbed the Satellite Beach croc capture and euthanize thousands of alligators per year, which has not slowed their population growth.

Movin’ on up

American crocodiles are also following mangrove forests north as the Atlantic Ocean heats up due to climate change: South Florida waters have warmed about 1.5 Fahrenheit in the past century. The rising temperatures are nurturing mangroves’ expansion into areas such as the Indian River Lagoon, which is part of the Banana River, says Mazzotti.

Many other species of flora and fauna will join them in their progression north, such as native snook fish and introduced species such as Burmese pythons and Cuban tree frogs.

“We’ll be seeing a lot more crocodiles in the coming years,” says Mazzotti. “It implies that the crocodile population is recovering. That is good news for all of us.”

Rebecca Renner is the author of the new bookGator Country: Deception, Danger, and Alligators in the Everglades.