(lighthearted music) (engine whirring) (water sloshing) - There's only one place in the United States where you can find wild native crocodiles: Florida.

It's also the only place in the world where crocodiles and alligators live side by side.

But some of the strangest surprises lie in one of Florida's most unexpected locations.

(mysterious music) This isn't a wild swamp or a hidden river.

It's a vast manmade maze of water stretching for miles in the shadow of a nuclear power plant.

(compelling music) Why do crocodiles gather in this unexpected place, and how has the landscape shaped by splitting the atom become home to one of America's rarest predators?

(compelling music) (upbeat music) South Florida, the land of sun-soaked beaches, palm line streets, swanky south beach hotels, and crocodiles.

(pensive music) American crocodiles to be exact.

Cousins of the Nile crocodile, these aren't invasive species like so many of Florida's weird reptiles.

They are native and rare.

While they might look similar to their more common neighbor, the alligator, there are some key differences.

Crocs tend to be longer, they have narrower snouts with more visible teeth, and they have the strongest bite in the animal kingdom.

(pensive music) Fossil evidence tells us that crocodilians have been around for over 80 million years, dating back to the time of the dinosaurs.

Their lineage remains largely unchanged, which is a testament to their resilience at its peak.

(mellow music) At its peak, South Florida's crocodile population may have numbered 3,000 or more, but by the mid-1970s, those numbers had plummeted to just a few hundred.

(lighthearted music) But some of those elusive reptiles found an unlikely sanctuary, right here at Turkey Point Nuclear Power Plant just south of Miami.

(lighthearted music) Turkey Point was built in the 1960s to generate electricity for South Florida's booming population.

Energy from this plant powers nearly 1 million homes.

But what makes Turkey Point unique isn't just the size or location, it's what surrounds it.

(pensive music) - One of the misconceptions that we have is that there's some radioactivity to the cooling canals, and really, that's not the case.

The crocodiles here are living in the brackish water that is just cycling through the plant, but not actually touching any of the radioactive equipment.

- The canal system is massive.

It's 168 linear miles of cooling canals.

You can actually see it from space.

- [Joe] The water passes through the nuclear plant to remove excess heat.

The water then cools as it travels through the canals.

- [Jodie] So it works in the same way as the radiator.

Once the cooling water has exited the plant, it takes about 48 hours for it to cycle back through again.

- At first glance, this just sounds like an industrial solution to an ordinary engineering problem, but over the years, these canals have become something else entirely.

(suspenseful music) - [Jodie] Both of our nuclear units went into operation in the early 1970s, and then in 1978, while doing some work on site, we found a crocodile nest.

(pensive music) - [Mike] Crocodiles were in a lot of trouble.

We're talking about a population of about 150 to 300 animals in the '60s and '70s.

- [Jodie] The intention when we built the power plant and when we built the colon-canal system was not to have some amazing habitat for endangered species.

Once it was created and we recognized that we did have a crocodile nest here, it was really there that we started to learn more about the crocodiles that we had here on site.

(compelling music) We really have three things that are necessary for the crocodiles.

One, the cooling canal system is an ecosystem in and of itself, and so it has the prey that the crocodiles need to eat.

We have elevated berms that are used for nesting, and really one of the biggest reasons is because we don't have public on site.

(pensive music) - [Mike] We have this whole network of canals where crocodiles can live freely and not worry about human encroachment.

- [Joe] But the presence of crocodiles in these waters isn't just some strange nature sideshow.

They play a critical role in this ecosystem.

- [Mike] Crocodiles are at the top of the food chain.

Without them, the rest of the food chain falls apart.

They're the cleanup crew.

They keep other populations in check.

- [Joe] Unlike alligators, crocodiles can tolerate salt water, thanks to special glands that help them expel excess salt.

They prefer coastal, brackish, and saltwater habitats, the same habitats where the humans of Florida like to build homes.

- [Mike] As we built houses, we were taking away a lot of the habitat from the crocodile.

- So as the crocs of South Florida lost their preferred nesting habitat to human development, some of them turned to Turkey Point as a refuge.

(pensive music) Today, Turkey Point is South Florida's most concentrated nesting area for American crocodiles.

(engine whirring) And we know that, thanks to the work of people like Mike Lloret.

(pensive music) - Ever since I was born, I always had this innate obsession with reptiles.

So what bigger and badder reptile than a crocodile?

(jaunty music) Crocodiles are just extremely intelligent creatures, and we really haven't even scratched the surface of their intelligence.

(pensive music) Some of the myths of the American crocodile is that they're these basically bloodthirsty beasts.

They're nothing like that.

Although they're extremely efficient predators, they're actually very shy by nature.

(water sloshing) - [Joe] Each year, Mike and his team monitor hundreds of crocodiles here in the canals, tracking their growth, health, and nesting behavior.

It's part science, part detective work, sometimes part adventure.

- So, mother crocodile will come up here, she'll scratch.

She'll open the nest cavity, deposit her eggs, cover the eggs back up, and then go back into the water.

It'll be about three months of incubation until those eggs hatch, and she'll be coming up and down and checking on her nest and protecting her nest in the meantime.

(pensive music) This is actually a nest cavity that has already hatched, and you can see an egg fragment that's left behind.

Not too long ago, the whole clutch of little prehistoric hatchlings emerged from this nest.

(pensive music) Depending on the size and age of the female, you're looking at anywhere from around 20 to even up to 50 eggs.

(mellow music) Of the 20 to 50 eggs, a very small percentage will survive to adulthood.

We have to remember that when they emerge from their eggs, there are these tiny little creatures that are at the bottom of the food chain.

They feed pretty much every other predator out there, everything from birds, fish, turtles, even up to crocodiles as well.

Crocodiles are actually on the menu for other crocodiles.

- [Joe] As daylight fades, the real action begins.

This is when Mike and his team take to the canals tracking hatchlings and checking on nests.

(pensive music) - There's nothing else I'd rather be doing than chasing around crocodiles.

The best time of day to catch them is at night.

Yep, there's one there and there's one up there.

Basically, during the day, their camouflage is so good they're completely hidden from the human sight.

But if you go out at night and you wear a headlamp, you can actually see the reflection of their beady red eyes in the darkness of the night.

Capturing the hatchling crocodiles allows us to get a really good idea of the health of the animals here on site.

(crocodile geckering) Healthy hatchlings means healthy population.

(water sloshing) (pensive music) - [Team Member] Nice!

- [Mike] New one.

It's important to capture the crocodiles when they're really young because every minute that they're out there, they're learning more.

They're extremely intelligent.

(pensive music) - [Joe] Catching hatchlings is delicate work.

Each capture must be quick and careful to ensure the crocodiles are unharmed.

- [Mike] This year, we actually caught 529 hatchlings, which is the third most hatchlings within the history of the program.

(pensive music) After we catch the hatchlings, we take them back to the lab for processing.

Our federal permit allows us up to five days to process these hatchlings, but it's always our goal to get them back to the wild as quickly as possible.

- [Joe] Here in the lab, every hatchling collected in the field becomes a vital piece of the conservation puzzle.

- [Mike] We take a series of measurements, such as snout to vent length, total length, head length, tail girth.

All of these measurements will teach us about the health of the American crocodile.

(pensive music) Each individual croc gets two forms of identification, one being a pit tag, which is the size of a grain of rice, and it has a unique identification number.

It's the same pit tag that you would put to identify a pet cat or dog.

So we actually inject that into the base of the tail.

The secondary form of identification is actually clipping their scoots so that there is a visual form of identification that we can actually use to identify them without putting our hands on them.

- [Joe] Over the years, the scientists have tagged over 10,000 individuals, creating one of the most comprehensive data sets for any reptile species in the world.

- Crocodiles actually have the ability to cover a lot of ground in a little bit of time.

So every time we catch the crocodile, we're actually be able to compare the new data to the old data when we caught it initially, find out how far they've moved, how much they've grown over time.

So we have had crocodiles that have hatched here, but have actually popped up in golf courses in Tampa.

- But the ultimate goal with these little cuties is to get them back into the wild where they can grow and contribute to the recovery of their species.

Since the crocodile program began in the 1970s, the population in South Florida has grown from a few hundred individuals to more than 2,000.

It's a remarkable turnaround.

(uplifting music) Turkey Point is a conservation success story, a testament to the surprising ways that industry and nature can coexist.

- The American crocodile population was actually downlisted from endangered to threatened in 2007.

There's nothing more rewarding than to be able to help this species thrive.

- [Joe] Places like Turkey Point remind us that progress doesn't just have to come at nature's expense.

It can come with it.

It just takes a little energy to get things started.

(uplifting music)