My first nests!Elizabeth Willis ‘13 | June 16, 2010
I saw my first turtles nesting last night/this morning! We patrol Mounda beach at night in two groups and each group has two people. One group patrols half of the beach (Kaminia) and the other group patrols the other half of the beach (Potamakia). I was patrolling Kaminia with Ueli from Switzerland.
The first nest was on Potamakia. The group found the turtle at 11:40pm on Tuesday night and texted us to let us know they had found a nest. When we got there she had just begun laying her eggs. She was untagged, so we got to experience the tagging process.
Although the female enters a trance as she lays her eggs, when we clamped down with the tag gun she instinctively tried to pull in her flipper and it took a lot of strength to hold her flipper in place and finish the job properly. The turtle was beautiful, very young with a small shell and no barnacles or other distinctive markings except for a small spot on her shell, which was a lighter shade than the rest of her. Ueli and I had to leave early to patrol the rest of our beach but the other group watched the whole nesting process.
We found a nest a little later on Kaminia. It was very dark since the moon had set around 11pm.
I was leading looking for tracks when I saw a very obvious trail leading up the beach and a dark spot, which we assumed to be the turtle. We crawled up slowly and quietly until we were within close reach of the turtle and could determine the stage of nesting. It was 1:14am on Wednesday morning. The female was digging her egg chamber at this point and so when we
got up close she kept throwing sand at us as she scooped it out of the nest. A little while later she began laying her eggs, and we took all our measurements. Our turtle was tagged and was a slightly larger female than the turtle from Potamakia. Her tag number suggested that she had only been tagged last year and her shell size was only slightly larger so she must have only been a little older than the other turtle. When we were done with the first portion of data collection we settled down to watch the rest of the nesting process and record the times of each stage. We watched her lay all her eggs,
sometimes two at a time. The eggs are about the size of ping-pong balls, white and rubbery. They have a soft, rubbery exterior to prevent any damage to the embryos as the eggs are dropped into the egg chamber, dug about 20-50cm deep. After laying the eggs the turtle took a small break (she was breathing very hard throughout the whole nesting process) and then proceeded to fill the egg chamber, camouflage the nest and make her way back to the sea. She entered the sea at 2:02am.
Most turtles take between 1-2 hours to nest, and our female was on the lower end of that scale. Given the time she spent covering the nest and camouflaging it, we judged that she must have come out of the water around 1am, so the total nesting time would have been around 1 hour. The turtle on the Potamakia side took quite a bit longer. Watching the two females nest was an incredible and very exciting experience. From the time we noticed her tracks on the beach to the moment she entered the water and started swimming away I felt like I was holding my breath with excitement and awe. Sea turtles are very obviously meant for the water but their anatomy allows them to nest on the beach. While the female is nesting, you can sea trails of water from her eyes like tears, as if she is crying, but this is just one of the ways that turtles excrete excess salt from their system. The whole process was so
breathtaking a beautiful.
Our groups went to bed at 6am and the morning team took over the record the day’s data for the nest and its position etc. I really hope that we get more nests tonight so that I can experience the morning data collection too. The whole process is so fascinating! Turtles come to shore to lay nests during the nesting season approximately every 12-21 days after they mate in late April through May and early June. Since our first two nests were on June 5th we are expecting those turtles to come up and nest again within the next week or so and we are hoping for more females to come up and nest also. All in all, last night was a fantastic shift!