Friday, February 4, 2011
Leatherbacks lay from 55-85 eggs. The average number is 57. They come ashore 7-8-9-10 times a season to nest. The visits are 9-10 days apart. When they are not here, they are just about 50 miles out. Research has shown that there can be up to three males that fertilize the eggs...so three possible fathers, so to speak in a group of hatchlings. She mates at the beginning of the season and is able to store the sperm in her body until she is ready to lay. The survival rate of the hatchlings is only around 54%. Bummer...must be a reason, though.
A good book entitled Sea Turtles by James R. Spotila is a beautiful resource. He is one of the principal founders of this station and all that it researches and does I believe.
I have seen 2 sets of two hatchlings that were excavated two days after the nest first hatched. I excavated one nest yesterday. We put them in a bucket of wet sand with something over the pail to shade them and released them at night so they have a better chance of survival. The wet sand and shade revived them a bit. We took them down to the water's edge a make them crawl a short distance (guessing 30 yards) to get their muscles moving. Michelle says they start out just at the dry sand. It took them about 20 minutes or so, depending, to be in the water and swimming.
They crawl "fast," say the researchers, whatever that means! ??
There were many "cool" things about counting eggs: watching the eggs drop, feeling her contractions, being soooo close, watching how she could use her back flippers to dig so well (she never touched the side of the hole!), and being present at a "birth!"
The ideas you gave about adaptations are right on: front flippers for pushing through water and ridges and smooth skin for aero/water dynamics. I don 't know about the small head. Her mouth definitely has super amazing adaptations. In fact, all of her adaptations seem to be incredible. I only hope that she can be flexible for us human so she can rebound!
Posted by Ms. Elebash at 11:54 AM