On Saturday I memorized the location of the east-most stake that surrounded a Loggerhead nest site in case Isaac eroded the beach. The site was special for me because it's only a few hundred yards from where I live and I was anticipating the hatch some time during the first week of September. I triangulated the east-most stake surrounding the nest using three reference points. One was the edge of a window frame on the second floor of a two story hotel directly west. The other two points were farther to the north and south. For these two points I used corners of buildings that happened to line up with larger buildings behind them. The northern point was defined by a the corner of a six story building that was along a line of site that ended on the corner of a peculiar looking overhang near the top of a more distant highrise. I got down on my knees and made the same observation, memorizing how the line of site through the corner of the six story building moved the final spot on the overhang a little higher up the highrise. I reasoned that this would allow me to measure vertical beach erosion.
Please follow me below the orange M.C.-Escher-memorial-squiggle for what happened next.
During the storm on Sunday the stake nearest the ocean was torn out by waves in the surge. I struggled to pound it back in as waves crashed down on me. I nearly landed on the stake when a wave picked me up and tossed me. The storm was getting too intense so I left. I checked later Sunday night and the site seemed secure.
Monday morning I was shocked to see that the stakes were gone. Even though Isaac was well past South Florida, during the high tide on Monday morning the surge must have continued growing. I used my reference points to locate the nest. My best estimate was that a least a foot of sand had eroded. Seaweed traced a high water mark about two thirds of the way up the sloping, formerly level, nest site. The fact that the west-most stake was missing suggested the surge went well past the apparent high water mark.
Sea turtle mamas bury their eggs two or three feet deep for protection. This depth is crucial to final stage of hatching. The babies use a single egg tooth evolved solely to help them break free of their shells. When they break free they are curled up in a ball and can't straighten out. The umbilical cords to their yolk sacs are still attached. Their journeys to the surface takes three days! During this time they straighten out, develop their flipper muscles and lose their umbilical cords. Normally hatches happen at night but missing sand wreaks havoc with the timing and can result in babies emerging in daylight. The situation seemed grim but my estimate that perhaps only a foot of sand had eroded gave me hope. The high water line marked in seaweed also gave me hope that the egg chamber was still getting enough air in between waves. The volunteer coordinator told me that the eggs probably drowned under the surge or were swept away but she urged me to keep checking, even during the day.
On Tuesday I found shattered egg shells near the site. I hoped the shells were from old nests that had safely hatched but I couldn't help feeling that these shells were from my babies. Tire tracks from either the beach patrol or people illegally driving along the beach in their four wheelers crossed through the center of the nest. I collected enough coral to outline the nest. I traced the word NEST in two foot high letters on all four sides. Yesterday morning some of the coral was gone. Fresh tire tracks crossed through the nest. I collected more coral and repaired the perimeter. I retraced the word NEST.
Last night I visited the nest a little after 11 o'clock. I had my red LED flashlight even though the moonlight was bright. Sea turtles can't see the longer wavelengths of red light and can be harmed by light from regular flashlights, or worse, from the light of a camera flash. All I saw was the usual collection of seaweed, shells, bits of plastic, foot prints and so forth. Suddenly I saw a pea-sized chunk of loose sand move. I looked closer and the head and flippers of a thrashing baby turtle appeared!
I called Kath, a trained, licensed rescue volunteer. She was on her way home and happened to be nearby. A few minutes later a bobbing red flashlight approaching from the beach portal announced her arrival. She carefully inspected the baby and gently brushed sand aside in the manner that an Archeologist might do their work except that she used her finger tips. She said the baby was a preemie because she could see some of the egg shell. The normal routine for a hatch went out the window! This also suggested that at least two feet of sand had eroded. So much for my fancy vertical triangulation. She called her supervisor and they decided the best bet was to remove the nest.
For the next hour or so Kath continued to brush layers of sand aside, exposing more and more of the nest chamber, allowing her to remove eggs along the way and set them aside in little holding areas that she carved out from the sand. She carefully placed each slightly-larger-than-golf-ball sized egg into the holding areas in the same orientation that they were in when she removed them from the nest chamber. The eggs cannot not be tilted, or worse, turned upside down without leading to possibly fatal consequences. When she was convinced that she uncovered the last egg Kath put some sand in a five gallon bucket and began moving the eggs from the holding areas into it. When the surface was full of eggs she sprinkled sand until there was enough padding to transfer the next layer. She repeated this until 78 eggs were buried. Another two eggs were damaged and she placed them on top. The final three eggs had active "pips" poking their heads out and they too were placed on top. The one I originally found was the only one with flippers showing!
I carried the bucket to Kath's car. A five gallon bucket full of damp sand is not and easy thing to carry for hundreds of yards! Kath told me the babies would be allowed to hatch from the bucket at a nature preserve called Gumbo Limbo. She said that half would likely survive. She said that she would let everyone else in the volunteer program know what had happened and that there would be renewed hope that many of the other eroded, now unmarked sites might still be viable. Gumbo Limbo does not publicly report the results of individual mass rescues so I won't be able to report any final results.
Please send some good thoughts to my babies!