Thursday, July 27, 2006

Turtle walking, pt II

Good ole Edisto Sand

One of the things they told us in the lecture was that a large portion of the beach had been “renourished” over the winter. This is when offshore sand is dredged up and pumped on shore to replace beach that has been lost due to the action of waves and tides. [That barrier islands are in the long run rather mobile and do not respect the temporary structures of man and his concepts of property and real estate is a long discussion for another day.] This sand has a different texture than the original sand – it is hard for me now to say exactly how. My impression of it was that it was a finer texture but had lots of bits of broken shell and other debris. The rangers said that the turtles have noticed the difference, too and seem to prefer the “good ole Edisto sand” – the renourishment project ranged from the “town beach” into the state park, but did not reach all the way to the end – about a mile of the beach beyond the campground has “virgin” sand.

Stars

As our walk proceeded down the beach, passing the campground to where the island tapered to a narrow slice between marsh and ocean, we came to this virgin sand. At this point the rangers said that we would stay while they went on to Jeremy’s Inlet that formed the northern bound of the island and return to us. They said they could move a lot faster without us and one would come back to us if they encountered a turtle. Our little crowd dispersed somewhat as folks took a seat or laid down. I stretched out, with my arms behind my head and stared into the stars. As far as the coast of South Carolina goes, this is about as remote as you are going to get without a boat and accordingly has less light pollution than the more developed areas. Here the Milky Way was as pronounced as I had seen it in a long time. Strangely I could make out few constellations, not that I am much of a stargazer. We did see a satellite – a fast moving, unblinking speck of light tracking east to west. Warmed by the sand below, lost in the stars above and lulled by the rolling surf I lost all sense of time. If we never saw a turtle it would have been all right with me. I had more than gotten my money’s worth.

Return

The rangers when the spoke to us it was in low murmurs, those nearest leaning in and passing their words out to those in the outer rings. The words this time roused us to head back towards town with the same caution as on our outbound trip – the turtles they said were never more than a couple of hundred yards from shore and with their large dark adapted eyes, could see us quite well. It was their experience that the waiting mothers would watch us pass and make their landings when they thought us gone. So, brushing sand from clothes and collecting water bottles, we resumed our hushed march southward.

But wait…

Not more than 100 yards into the return we were halted with word that a turtle had been sighted. It was at this time that I checked the time on my phone and realized how little sleep I would be getting before my drive back, even if I could go to bed now. It was nearly 1:00am. I must confess to a moment of mixed emotions, I could hear my pillow calling to me… We were instructed to wait, that they would come and update us shortly. We resumed our resting positions and strained to make turtles out of the shadows in the murky surf ahead. A while later we got word that the turtle was starting to dig her nest – soon it would be safe to approach her without spooking her from her task. We returned to staring, convinced one minute that we could make something out then another certain we hadn’t.

We began to notice what looked like a flashlight in the far distance, later we would learn that the “turtle patrol” from the town had been called so they could see a turtle nest – many of their volunteers had not witnessed this. The inexperienced volunteers were scolded for their carelessness with their light…

By a red light

Then Elaine, the head ranger came back and huddled us up and said it was nearly time to move up and carefully approaching the turtle from behind we could watch her lay her eggs. We could see red glow of a small LED flashlight ahead – I assume that this had the same night vision reserving benefit for the turtle as it did for us – marking the location of the other ranger. We crept closer trying to get a glimpse of this much anticipated creature still shrouded in the moonless dark. I tried to lean in from the back of the tight crescent we formed around the apparent center of activity and could only make out the jagged silhouette of a creature from another age cast in red. As we swapped positions around so everyone could take a turn at seeing more clearly, the expected shapes came into focus, as did the unexpected size. As large as the empty carapace in the classroom was, this animate being seemed so much larger here a few feet away, perched over a cavity in the sand.

In the dim red light we see what do indeed look like wet ping pong balls dropping one by agonizing one 18 or more inches into their temporary resting place. That this is a labor in both senses is obvious. At one point Elaine tells us that she will shine the light on the head of this transient mother so that we can see her face – black saucers stare out of a mottled head that actually is the size of bowling ball, a beak hooking down. We sense she’d rather we weren’t there. We retreat into her blind spot.

Slinging sand

Soon the rate of eggs dropping diminished and we were cautioned to stand back. This mother will first fill in the hole of her nest then disguise its location – all with her back flippers. The same that she has excavated it with. These clumsy 18” appendages start shoveling the pilled up sand around the opening and as that fills in began to sling sand back and forth – not wildly, but with a pause to rest between each effort. Soon , we’re not sure exactly where the nest was.

It is now that we consider themagnitude of her effort. By this time, this 300 pound creature has crawled up out of her native element returning to that of her hatching, dragged herself across 50 yards or more of this gritty beach with limbs made for swimming, found a place to her suiting, excavated as deep as she can reach, deposited 80 or more little embryonic capsules, concealed them and must now return to the sea.

Conclusion later...

In this picture, you can see the turtles tracks arcing from the lower middle, sweeping up and right then back to the left.

Saturday, July 22, 2006

Turtle walking, pt I

I was supposed to have been at work that day, but I succumbed to the persuasion of my wife. My family was on a month long stay at the beach, courtesy of my in-laws. I had come down for several three day weekends – this would be the last one for this year. My wife talked me into staying an extra day, saying I could take one less day than I had planned for at Christmas. A helpful coworker rescheduled what meetings I did have on my calendar.
I had forgotten that she and her father had signed up for a ‘Turtle walk’ that night at the state park. He graciously said I should go in his place. The walk was not to take place until 9:30, so we went to dinner before heading out. We watched the sun go down over the marsh while eating some fine local shrimp and a steak. I washed mine down with a cold beer. We headed over to the state park a little early.

The weather was beautiful – just warm and with a nice sea breeze keeping the gnats and mosquitoes out of play. The sky was a darkening indigo with only the occasional high wispy cloud to be seen. There was no moon. We made our way to the classroom where the lecture preceding the walk was to be held. I had been here a day before with the older two of our children for the kids version of the program we were here for tonight. The kids program consisted of a lecture and a walk on the beach to look at the tracks of nesting mothers and the nesting sites – original and relocated. Children under 10 are not invited on the nighttime walk because of the late hour and the patience and silence required for the long walk (both in time and distance). I would find out how long (in time) that the walk would be later…

Lecture –

The state park staff is licensed by the Federal government to work with the Logger Head Sea Turtles who nest on this island. Part of their mission is education and they do a good job of it. Though I heard again most of the same facts that I heard in the previous presentation, the enthusiasm, or rather passion of the head ranger kept my attention. There aren’t many of these ancient critters left and we could easily be the last generation that knows them first hand.

Walk and night vision –

The rules for the walk are that we follow along behind the two rangers about 20 yards behind. With no flashlights, no moon, little ambient manmade light, and the light of the stars, the rangers are invisible to us who are not at the front of the pack. Our steps are guided, and stopped, by those in front. We, in turn guide those behind. The murmur of voices and shuffling of feet on sand is almost drowned out by the surf. Our eyes adjust, the world is cast in fine shades of the darker grays and lighter blacks. As our eyes adjust to the darkness – it really does take 10 or more minutes to reach your maximum sensitivity – we can see what they told us, the surf does glow dimly and is the brightest of areas down below the dome of the sky. We strain to make out anything in the shifting murk – we’ve been told what to look for – the appearance of a log floating in – but in dark tumbling surf, I lose all sense of scale and realize that it will take eyes more practiced than mine to see anything. Occasionally we are stopped as the rangers think they have spotted something or when those in front think the rangers have stopped.

Lights –

As we proceed away from the main park area, we leave the bright light at the Pavilion’s pier behind – this is the brightest light on the beach. I’m not sure why it is exempt from the “lights out rule”, perhaps because that would not be a good place for turtles to nest in the first place. The next light we encounter is the light at the state park’s campground bathroom. Though the ranger explains that they have tried various ways to minimize the light here, we (the herd) are still puzzled that a problem as seemingly simple as this could not be solved. As we work our way north along the beach, we can see the lights of distant houses, across the marsh, and the even more distant lights of Charleston. Even though the primary focus of the “lights out” program is the beach, our head ranger relates an anecdote of a homeowner on a creek behind the island who called her one night late in a panic. Baby sea turtles were climbing up on a dock shared with her neighbor and had been doing so for an hour. The ranger asked if her light was on and of course it was. The turtles had hatched, swarmed out and had seen this as the brightest light, distant as it was and unfortunately in the wrong direction.

More later...

This picture is from the day time walk with the kids. She is showing us where a turtle had nested the night before, her tracks were still visible. The rangers relocated this nest to get it above the high water mark. The pieces of straw in the were how they kept count of the eggs as they moved them - this nest had over 80 eggs (low end of the range).