Sea turtle nesting: Ways you can help

June 7, 2022

How often, alone, do we expose ourselves to the midnight hour? To the boundary of civilized and savage? A ribbon of sand between the tame and turbulent, the known and unknown. Where darkness renders our vision lacking, but our hearing sharpened. It’s here, in the shadow of the earth, where the human imagination often runs wild.

In the solitary darkness, you feel the wet sand between your toes, scratching your heels. Sandflies biting into your bare skin. The urban glow of the city (Naples, FL pop. 20,000) obscures the stars above an empty beach. Silent flashes of distant lightning mesmerize you while the cadence of sleepy waves calms your nightly nerves.

The beauty of the night washes away the worries of the week and you sink into silence.

But something rustles in the bushes, echoed by a squeak in the sky. The vulnerable feeling of being alone returns once more with its sharpened edge. Your body tenses. The wind quickens hastening the tempo of the tides and the slap of a wave that finds you flinching. Another spark of lightning illuminates the beach as you turn to investigate, this time it isn’t empty. Something appears as the wave recedes. Something big…

“Sea turtles are among the most confirmedly aquatic of all reptiles. In body form, musculature, and behavior they are all drastically modified for successful life in the water. But they have retained one old reptilian feature that ties them to the land”(So Excellent a Fishe p.83).

Interns working with a nesting loggerhead sea turtle on the beach
Permitted Loggerhead nesting research being conducted by interns at the Conservancy of Southwest Florida

With single-minded determination, females, like the one in front of you, emerge from the ocean every 2–4 years. This migration from their foraging grounds further exposes them to risks they ordinarily encounter; entanglement in fishing gear, boat strikes and poachers on their nesting beaches. This process will be repeated not just once, but as many as seven times in a season (April to September), an insurance policy against nests lost to storms and eggs lost to predation (animals eating the eggs). Sea turtles are one of the greatest bet-hedgers in the animal kingdom.

Worldwide, there are seven different species of sea turtle, all seven of which are considered endangered or threatened. Here in southwest Florida, however, you’re most likely to see a loggerhead (Caretta caretta), a species designed for the long haul, reaching maturity at roughly 32 years old.

From far and wide these venerable, oceanic commuters converge with incredible accuracy, riding on the coattails of warming summer oceans, heeding the call of hormones and the urge to nest. Though simple in theory, nesting is a complex puzzle and each decision this female makes plays a crucial role in the fate of her hatchlings.

Newly vulnerable and exceedingly vigilant she takes in bizarre, yet oddly familiar surroundings. Breathing in deeply, she inflates against the crushing force of gravity, bearing the full extent of her earthly weight (150 to 300 lbs) for the first time in years.

Though your nerves may urge you to investigate, leave her to her own devices (no lights and give her space). Her cargo is crucial to the longevity of the species and if she’s spooked she’ll quickly return to the sea. Millions of years of evolution have ingrained in her the fact her survival is of the utmost importance. She can always return later.

Description of sea turtle tracks

As you cautiously back away she begins her ascent, heaving her heavily armored body, covered in barnacles and algae, up the beach. One flipper at a time, she’ll leave a track of alternating, comma-shaped marks in the sand. Only green and leatherback sea turtles will leave parallel tracks as they use both front flippers at the same time.

If she doesn’t find the right conditions she’ll make what’s called a “false crawl” and head straight back to the ocean. But, lucky for you, she decides it’s a good spot and sets to work immediately. With powerful strokes she begins throwing sand aside with her front flippers, digging what’s known as a body pit. This body pit allows her to vary the depth of the nest beyond the reach of her rear flippers. By adjusting where and how deep she digs she can influence a whole host of environmental variables.

“One of the important functions of the nest is to provide the eggs and young with a way to avoid desiccation (drying out), flooding, and temperature fluctuations. The nest must be deep enough to damp down the daily changes in weather and to keep the eggs in continuously moist, continuously warm sand, and yet not so deep that high tides in the sea flood it and drown the embryos in salt water.”

(So Excellent a Fishe p.82)

With the body pit dug to her liking, she begins the process of excavating the nest chamber. One rear flipper at a time she will dig with all the dexterity of a human hand, removing roughly a cup of sand with each pass until she’s left with a perfectly constructed, flask-shaped chamber. When her rear flippers can no longer reach any sand to pull out she’ll start to deposit her eggs in series of ones, twos and threes.

Now, the number of eggs that will be deposited is a balancing act and a key piece to the puzzle that will decide the fate of her offspring. Increasing the number of eggs would make sense to most of us, but a female turtle can only carry so much weight and if she increases the number of eggs she must decrease the size of them leaving the hatchlings with smaller yolk sacks and a decreased chance of survival. On the other hand though, if there are too few they will surely be picked off by the myriad of predators that eagerly await their emergence into the sea.

That being said “the size of a complement of turtle eggs is no mere accident and not simply the payload that a lady turtle is able to swim with. It is a number packed with ecology and evolution” (So Excellent a Fishe p.74). It’s a formula, a blueprint laid out by history and evolution that has allowed them stay one step ahead in the game of survival, but is it enough anymore?

As she finishes laying and covering up her eggs (up to 3 hours in total) the moon begins to peek over the houses and trees to the east. Through its faded light you have a dimly lit view of her melting back into the glassy waters of the Gulf, consumed once again by its safe embrace.

A caged Loggerhead nest on Keewaydin Island
A caged Loggerhead nest on Keewaydin Island

Is biology enough anymore?

Millions of years of life on this planet have equipped sea turtles with the adaptations and intuition to survive, but nothing could have prepared them for the immensity of modern man. We are, without a doubt, the biggest threat to the endurance of a lineage that survived the extinction of the dinosaurs (65 million years ago).

From poaching to fishing by-catch to pollution and habitat destruction, humans influence sea turtles more than any other species on earth, bringing them right to the cusp of extinction. With that in mind, humans have a choice. Either continue to contribute to their demise, or acknowledge their beauty, and rightful place on earth and become their greatest advocates.