Sea turtles hatching on Florida beaches are feeling the heat from warming climate

Hot sands make for a gender imbalance worse than the one in The Villages

November 17, 2022 7:00 am

Professor Jeanette Wyneken of Florida Atlantic University shows off a newly hatched sea turtle. Credit: FAU

When anyone asks me what’s the coolest thing I’ve ever covered, I always tell them about the sea turtle: I once witnessed a loggerhead turtle crawl onto a Sarasota County beach in the dark of a new moon, dig a hole, and lay a bunch of eggs.

That night, I was riding with a couple of volunteers who patrolled the beaches marking turtle nests so they could be protected from beachgoers. Around 2 a.m. we spotted this one. We watched the mama turtle pull herself out of the water, find a good spot to make her nest, and then start laying.

When she was done, she covered the nest, dragged herself down to the surf, and began swimming back out to sea. As her flippers stroked through the black water, green lightning flashed from the tips — brilliant streaks of bioluminescence.

Loggerhead sea turtle hatchling. Credit: The Turtle Hospital

You can see how that transcendent experience left me feeling emotionally invested in the annual turtle nesting season reports. This year’s season, which just ended, delivered both good news and bad news.

On the one hand, as the Fort Myers News-Press recently reported, “Hurricane Ian couldn’t wash away the best turtle nest season ever in Southwest Florida. Nesting season runs from May 1 to Oct. 31 and luckily most of the nests had hatched by the time the big storm destroyed the local beaches.”

On the other, the turtle hatchlings from those nests are likely to turn out to be just one gender: all girls.

Having a lot of female turtles is not a bad thing in and of itself, of course. For instance, it’s a safe bet that, while migrating, the male turtles never want to stop for directions, then waste a lot of time paddling the wrong way. Females won’t have that problem.

But if you’ve studied basic biology — or ever visited The Villages — you know what happens when a population has a really large gender imbalance.

In The Villages, for instance, there are 10 women for every man, which has led to such consequences as a thriving black market for Viagra. Those women have to be very, very determined.

“But how do you know that the turtles are all going to be girls?” you ask. “Are you clairvoyant? And if so, why haven’t you picked the winning Powerball numbers, collected your big check, and moved to Cassadaga, the Psychic Capital of the World?”

I am not clairvoyant. I don’t even own a Magic 8-Ball.

I know the gender of the turtle hatchlings because this is not a new phenomenon. Just ask Bette Zirkelbach, who for the past 11 years has managed the Turtle Hospital in Marathon. The hospital cares for a lot of juvenile sea turtles during nesting season.

“We have not seen a single male juvenile turtle in the past four years, which is frightening,” she told me.

What’s behind this extreme lack of turtle-boys, whether teenage mutants or not?

I’ll give you a clue, folks. It’s also the name of a Robert DeNiro-Al Pacino crime movie: “Heat.”

The turtles’ story

Listen, I don’t want to rile up Gov. Ron DeSantis’ semi-hysterical gender-identity army. I don’t want his hand-picked Board of Medicine and Big Donors to announce a new rule that sea turtles MUST identify as males no matter what they are or what their parents want.

Sea turtle sexuality doesn’t work the way ours does (not that the way gender works in humans seems to matter to the governor’s minions).

Unlike humans, baby sea turtles don’t start out with chromosomes that grant them a specific gender. Instead, the circumstances of their egg’s incubation — specifically, the warmth of the sand — decides whether they will be boys or girls. Warmer sand equals more girls.

Florida plays an outsize role in the reproduction of loggerheads such as the one I saw so many years ago. Scientists estimate 90 percent of all the Atlantic Ocean’s loggerheads lay their eggs on Florida beaches. Then the ones that hatch here come back years later to lay their own eggs.

But something funky is happening on those beaches, and it doesn’t involve James Brown.

Loggerhead sea turtle hatchlings. Credit: The Turtle Hospital

Starting in 2002, a Florida Atlantic University professor named Jeanette Wyneken began monitoring sea turtle nests on Palm Beach County beaches to check the temperature of the incubating nest. As soon as a new nest appeared, she or one of her team of researchers would insert a probe that would stay there as long as the nest lasted, measuring the temperature.

“Our goal was to find out what was the normal sex ratio,” she told me. “I thought it would be one of those two- or three-year projects — that’s all.”

Twenty years later, Wyneken’s team is still at it. They kept checking nest temperatures because what they found was so alarming.

The first year, she said, they found 65 percent of the hatchlings were female, which in retrospect was a pretty good number. The beaches had been cooler because 2002 brought a lot of rain, she told me.

But the next year it was drier and the females made up 95 percent of the mix. The year after that, the females made up 98 percent.

In the years since then, she said, they have found “100 percent female years, 99 percent female years, 98 percent female years. There are very few years where we’ve gotten even 10 percent males. It’s worrisome.”

This year, she said, a rainy April and May led to two nests of males hatching, “but outside of those two nests, we haven’t seen a male since then.”

The mysterious disappearance of the male turtles is really no mystery at all. Not if you’re paying attention.

“The turtles are telling us a story,” she told me, “and it’s not just about turtles.”

Catch-22 for sea turtles

Climate change is making everything in Florida hotter.

And not in the fashion sense, either.

Florida was already pretty warm from being located so close to the Equator. But gradually, thanks to the greenhouse effect, our days are getting warmer. So are the nights. The farmers’ fields are growing hotter. So are the theme parks, the fishing piers, the skate ramps, and the drive-thru lines.

So, too, are our beaches. And that’s important not just because when you cross the sand to the refreshment stand you have to run reeeeeeally fast (a move often referred to as “hot-footing it”).

Remember how the temperature of the sand determines the gender of the turtle hatchlings? Hotter beaches mean fewer male turtles. Only on the rare occasions when the sand cools down — say, because of heavy rains — do the males reappear.

The dwindling number of males is further proof that climate change is not, as a certain not-yet-indicted Palm Beach club owner/presidential candidate once contended, a Chinese hoax. It’s as real as your rising property insurance rates.

But if the sand gets too hot? The hatchlings don’t hatch at all, Wyneken said. Or if they do hatch, they exhibit a sideshow variety of defects: no eyeballs, or a missing jaw.

The Florida Keys-based Turtle Hospital in Marathon, Fla., is the only state licensed veterinary hospital in the world dedicated solely to the treatment of sea turtles. (Andy Newman/Florida Keys News Bureau)

If the weather is getting too hot to produce male sea turtles, she said, “then it’s too hot for insects and too hot for plants and too hot for us, too.”

However, as we learned from Jeff Goldblum in “Jurassic Park,” “Life, uhhh, finds a way.”

According to Kate Mansfield, who runs the Marine Turtle Research Group at the University of Central Florida, the sea turtles may find a work-around for the havoc we humans have caused.

The turtles could start their nesting season earlier to avoid the heat of the summer, or could show up later in the season, once the weather becomes more temperate.

There’s a downside to that second option, Mansfield noted. The later the mama turtles lay their eggs, the more likely they will be destroyed by a hurricane. Climate change is making those stronger.

“It’s a Catch-22,” she said.

A golf cart caravan

For 12 years, Florida’s chief executive has been someone who can’t even bear to speak the words “climate change.”

First it was eight years under Rick “I’m Not a Scientist And I Don’t Care About the Seas Swallowing My State” Scott. Even as storm surges around Florida crept higher and the temperatures rose and more people suffered from heat-related ailments, Scott kept dodging the issue whenever it came up.

Then it was four years under DeSantis. He’s been fine with spending millions protecting waterfront property from being inundated, but refuses to do anything else.

Worse, DeSantis and our fine Legislature made sure last year that our local governments are locked into burning fossil fuels rather than switching to greener energy sources.

The most recent election guarantees that streak of denial will go to at least 4 years. That’s when DeSantis will officially become a candidate for El Supremo — er, excuse me, president.

I asked Wyneken about how she deals with Florida’s officially sanctioned support for making climate change worse. She told me that she’s calculated her own carbon footprint and encourages everyone she meets to do the same.

As a result, she tries to lessen her personal contribution to the world’s greenhouse gases in every way she can — limiting her driving trips, for instance.

But it’s difficult, she admitted. For instance, she has to drive an SUV, not a more sensible vehicle, because sometimes she’s transporting full-grown sea turtles. And when she does, she has to run the air conditioning for them.

My suggestion would for those of us who are concerned about this to recruit some of those extremely determined women in The Villages. They’ve got the resources and the will to deal with the men in that suburb, so that means they’d be up for the challenge of dealing with this situation too.

We could get them interested in helping by showing them a series of super-cute pictures of the turtle hatchlings. Those things are so cute they could break the official Cute-O-Meter. Close-ups are particularly compelling, I’ve found.

Once they’re convinced that we’re facing a major sea turtle crisis, I’m sure they will hop in their fancy golf carts and hit the road to take care of the problem.

They’ll caravan to Tallahassee. They’ll track down those useless legislators who won’t lift a finger to halt our spiral into a sweltering hell. And then those women will crank up the heat on THEM.

And if they need directions, they’ll stop and ask— unlike us men.

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Craig Pittman
Craig Pittman

Craig Pittman is a native Floridian. In 30 years at the Tampa Bay Times, he won numerous state and national awards for his environmental reporting. He is the author of six books. In 2020 the Florida Heritage Book Festival named him a Florida Literary Legend. Craig is co-host of the "Welcome to Florida" podcast. He lives in St. Petersburg with his wife and children.