4. Hatchlings

45 to 65 days after laying, the eggs, buried 1metre deep in the sand, hatch. This time will vary according to the temperature, with cooler temperatures causing longer incubation periods. The peak hatchling period on Ascension Island is from February to July.

The hatchlings spend 3-5 days climbing up through the sand and usually emerge onto the beach at night. They can tell it is night because of the cooling of the sand near the surface.

(Pictures: left, a model of turtles hatching out / right, hatchlings scurry to the sea.)

The hatchlings are attracted to light and the reflection of the stars and the moon on the sea assist them in locating the water.

Artificial lights near a nesting beach can be fatal for hatchlings as they head away from the sea towards the lights.

The lights of Georgetown are yellow rather than white, which reduces the disturbance to nesting females and hatchlings. Once they reach the sea, having avoided birds, crabs and feral cats, the hatchlings must run the gauntlet with the fish.

They then head out to the open ocean where they spend the first few years of their life before settling into near-shore habitats.

It is estimated that only 1 in 1000 will survive the next 30 years to adulthood. The sex of the hatchlings is determined by the temperature at which the nest incubates, and not genetically as is the case with most animals.
Nests incubating at 29 degrees Centigrade produce a 50:50 sex ratio. Above this temperature, a greater proportion of females are produced, and in nests cooler than 29C, a larger number of males are produced. As the temperatures tend to be 26C, recent research has shown that on Ascension Island most of the hatchlings are female.
Last revised on the 21st of April 2002 by Stephen Fowler.