To Trap a Turtle

A story of satellite tagging sea turtles

Leif Johnson
Environmental Science Department

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Feeling like a partially wrung out sponge, I waited patiently for the animal to return, leaning heavily on a sand-covered ATV in the starlight. The rain jacket covering my head and shoulders was saturated from a midnight shower four hours earlier that had rendered it almost useless. I wore a sun mask around my face though there was no sun to mask. I tolerated its damp, musty smell purely because it helped keep the bugs out of my ears and nose, a job which it mostly accomplished. Three nights worth of bug bites covered my wrists and hands, the only parts of my body, aside from my forehead, I’d neglected to cover. I’d become more or less used to the incessant itching sensation that left me scratching most days, but still, I swatted at mosquitoes and sand flies in a futile attempt to prevent future itching.

Keewaydin Island, the eight-mile stretch of barrier beach I was working on that night sits along Florida’s Gulf Coast between Naples and Marco Island. A perfect puzzle piece of coastline separated from land by Gordon Pass to the north and Little Marco Pass to the south. Its long, thin beach stretches at a slight angle from the north-northwest to the south-southeast.

Keewaydin Island

From where I stood the lights of Naples and Marco glowed like distant bonfires on the horizon to the left and right. The big dipper hovered just over Naples, the bottom two stars (Phecda and Merak) of its ladle obscured by the cities glow, while directly overhead, leaning slightly to the south between the light from the two cities was the milky way.

My overarching reason for standing sopping wet on the beach slapping bugs that night was to monitor the beach for nesting sea turtles, something the Conservancy has done on Keewaydin continuously since 1983. At that moment though I was focused on keeping a single green sea turtle (Chelonia mydas) that was nesting in the vegetation in front of me from crawling back into the ocean. I needed to encourage her to stay on the beach long enough for my coworkers to arrive and fasten a satellite transmitter to her carapace (shell). It may not sound like a daunting task as we don’t think of turtles as being “fast” in the typical sense, but keeping a 300 lb. sea turtle on a beach longer than she wants to is no simple feat, a lesson I was soon to learn.

The way I was supposed to keep her from the water was by restraining her in a box. A wooden one to be specific, composed of four separate boards, two long, two short, and held together with pieces of rebar (metal stakes) threaded through holes on the corners.

The box is an awkward heavy thing, no miracle of engineering design, but its beauty lies in its simplicity. When it’s not staked into the ground, however, there is very little structure to it, so, in preparation I only had three sides assembled; the two long sides connected to one short side by stakes at the corners. My hope was that it would be easier to maneuver and line up with the turtle and that I could install the fourth side once it was properly situated. As I waited for her to finish nesting, a reproductive rite that often takes a green turtle hours, I left it standing upright in the sand in front of me, ready to go at a moment’s notice.

Photo by Jesse Schoff on Unsplash

The green sea turtle is arguably the most iconic of all the species of sea turtles, and debatably, not all that green. The name comes more so from the color of their fat, due to a largely herbivorous diet, rather than the color of their exterior. Green turtles were the principal target of the marine turtle fishing industry before the animals were granted protection in the U.S. under the newly established Endangered Species Act in the 1970s. Before those protections were established though, most species of sea turtle were heavily sought after for their meat, of which green turtles’ was most highly prized for dishes like turtle soup, a delicacy in parts of Europe.

If you see a sea turtle nest near Naples, Florida, chances are it was deposited by a loggerhead (Caretta caretta) as they are the predominant species that nest along our coastline. Green sea turtles, however, will occasionally make a visit to nest here as well, something they would have historically done, in all likelihood, in much greater numbers.

Greens are an endangered species as opposed to loggerheads, which are listed as threatened. Though the occurrence of green turtles nesting in Collier County appears to be on the rise in recent years, green turtle nests are still not all that common. Scientists are increasingly interested in where these nesters come from, what they do between nesting events during reproductive season and, during the intervals when they aren’t nesting (2–4 years), as well as where their foraging areas are located. My coworker Dave Addision is one of the scientists interested in these behaviors. Learning more about their movements along this coast would be extremely helpful in our quest to conserve and protect the species from extinction. If we know what parts of their submerged world they spend the majority of their time in then we can work to protect those areas for future generations of marine turtles. Hence the use of satellite tags, electronic tracking devices, which allow us to track a turtle’s whereabouts long after they’ve disappeared back into the ocean.

In order to get one of these trackers on her back and collect that all important locational data, I stood watch while my coworkers made their way over to the island from Naples with the tagging equipment. As I loitered about I turned my back on the turtle for a moment to face the ocean, hoping it might grant me a ceasefire from the bugs, though no such agreement was reached.

Distant storm clouds sat over the Gulf to the south, tall black shapes on a moonless night. I was thinking about how the sound of these tiny waves always seems louder than it should be when I noticed something in the surf. All too often this just ends up being a brief shadow created by the wave as it folds over itself and flattens on the shore, but this shadow didn’t disappear when the wave fanned out. It continued slowly but persistently advancing up the beach. Another turtle, not 50 feet from the one on which I was waiting, but this time it was a loggerhead. I watched her patiently lug her weight up the beach now that the full force of gravity bore down on her without the buoyancy of ocean water to offset it. A black shadow barely discernible in the dark.

A loggerhead sea turtle nesting under a full moon.

My objective though was to stay with the green so I let this one go about her business undisturbed.

After listening a while longer to the wash of the waves I heard the distinct sound of a turtle pulling itself across the sand. Our turtle had begun making her way back to the water, my cue to get to work.

Dave had always warned me about not boxing them in too close to the vegetation where the mosquitoes and sand flies are worst, so I let her make her way out from the grass a bit before making my move.

As the turtle approached me I started doing some quick mental math looking to the turtle, then to the box, then back to the turtle again, realizing that the animal may very well be too big to actually fit in the contraption. I didn’t have much time to make changes though and began approaching her, straining my eyes in the darkness to better make out her shape.

As I moved forward, awkwardly heaving the three sides of the box up the beach in front of me it was obvious she could see me coming, even in the dead of the night, and she began to veer away with somewhat surprising speed. It was around this time I realized this was going to be more difficult than I’d foolishly imagined. Without much beach to work with before she reached the water, I decided I needed to move quickly as there was very little I could do to slow her down. Making my move, the first of many attempts to enclose her in the box, I put the three pieces of wood in front of her attempting to line them up as best I could for the fourth piece to be put on, but, before I could swing them around her, she pivoted and with little effort shoved them aside. The apparent ease and strength with which she did so surprised me. I backed away a bit wondering how the heck I was going to do this before quickly moving to catch up as she hustled away. I made one more attempt before realizing that the box was indeed going to be too small and that I needed to adjust it to the wider of its two settings. With adrenaline coursing through me, I adjusted the pieces of wood while watching as she moved ever closer to the water, just 40 feet away. With the sides reset I once again awkwardly stumbled forward with my turtle trap. I walked behind her thinking she would have to rest soon, but she kept right on going, forcing me to cut off her retreat. With the boards set in front and alongside her she seemed to finally take a break so I doubled my efforts thinking this was my chance. I pushed the two rebar stakes at the head of the box into the sand as far as I could then ran to grab the last side and the other two stakes which had been left behind in my haste to stop her. My hands were shaking as I tried to thread the final stakes through the holes to lock it in place, knowing she could break it apart at any moment if she wanted to. With three stakes secured I got to work on the fourth, anticipation building for her to bust it open again. I had the stake halfway through, but the back of her shell was pushing out against the side of the box forcing the bottom of it out at an angle. I pushed and lifted with everything I had to inch her forward, my feet digging a trench through the sand like a lineman pushing a sled, but I could barely move all the approximately 300 lbs. of her. Sweat beaded on my forehead as I strained to gain the last millimeters of space when finally I was able to get the stake through the hole, just before she released another flurry of flippers. I ran from one rebar stake to the next pushing them in as far as I could in order to keep the box together and the turtle contained as she leaned into the sides.

Exhausted from the effort, but confident I had her secured, I finally slumped down next to the box taking notice for the first time of the sweat pouring down my face and the apparent lack of biting insects, a moment of relief that wouldn’t last long. I wondered to myself if the loggerhead nesting in the vegetation behind us had seen any of what just transpired and what she might be thinking of the odd spectacle.

Adrenaline fizzled through my body as I looked up at the stars. The big dipper was still in its same spot over Naples, faithfully pointing to the North Star, Polaris. Clouds rolled quickly overhead blanketing patches of sky as they headed inland so I moved to see if they had company. Before I had turned all the way around I could tell the excitement was far from over. The wall of storm clouds I had forgotten about was advancing, still hovering over the ocean to the southwest, masking parts of Marco; a sight which left me feeling rather vulnerable in my exposed position on the open beach. I sat back down facing the ocean and whispered to myself “hurry up guys.”

After what felt like an eternity, but in reality, was closer to a half-hour, Dave and the others finally appeared on the beach to the south, the red lights of the ATV’s giving away their advance. It was still pitch black out, though the first rays of light would be appearing soon, piercing through the treetops to the east. Its arrival couldn’t come soon enough though as with it would come relief from the bugs.

Dave’s silhouette on the beach under a full moon

I sat on the edge of the box as they pulled up and watched as the loggerhead that had been nesting next to me crawled into the sea, a shadow consumed by the waves.

With everyone there, we set to work activating the satellite tag and attaching it to the turtle’s carapace with strong two-part epoxy, a process which would take a couple of hours to complete. We were all painfully aware of the storm’s presence offshore and it loomed heavily in the back of our minds as we worked, taking frequent glances toward the ocean. It seemed like there was no way we were going to get out of this without at least getting poured on as the radar continued to display the ominous image of a red mass inching our way. At one point, I looked south only to find Marco Island had disappeared, swallowed by the storm. The only bit of comfort came from the lack of thunder and lightning and, as the minutes slid past, the storm continued to keep its distance, sending only clouds in our direction. The turtle gods seemed to be smiling down on us.

The green sea turtle with a satellite tracker being fitted to her carapace

Before the sun broke the horizon its rays set fire to the storm clouds high above like a Floridian alpine glow. The clouds twisted and snarled in deep furrows, continuing to rain down on the ocean as the sun lumbered into the sky. Rain and light soon combined to create a rainbow which vaulted out of the ocean, contrasting intensely against a backdrop of clouds and blue sky. We stood in awe under the rainbow, watching as it eventually became a double, one of the most magnificent sights I’d ever seen in my life. Pelicans, ospreys, and all manner of shorebirds winged their way across the scene, painted vividly in the growing morning light.

The rainbow arcing over the gulf, the second rainbow dimly lit to the left.

Keewaydin was showing off and we were all mesmerized with her performance.

With the tagging efforts complete we removed the box from around the turtle and stood back as she made her way down the beach. We all watched in amazement as she slid back into the waves, a final touch to complete a once in a lifetime picturesque scene.

The turtle returning to the ocean with the satellite tracker on its back. The second rainbow is just visible in the top left corner.

In the days and weeks to come, my conversations with Dave would often float back to that night. I was surprised to hear how much of an impact it had on him, considering his 30 years of work on the island. To hear him recount it so fondly spoke to just how magical and rare the entire experience was. The beauty of the night, for me, made evermore intense by the struggles required to make it a reality.

Though it only exists in memory now, firmly entrenched in the past, the work we did and information gleaned will undoubtedly help bring about a brighter future for the species and, I hope paving the road for generations to come.

To learn more about the Conservancy’s environmental science research click here.

*All the above research activities were conducted under FFWCC permit number MTP-19–116

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