Under the #timingiseveything a new photo collage was posted on the SIF Aldabra Reserach Team's FB page. The post reminds us how fragile a turtle population is.
The number of eggs in a nest (clutch) varies by species. On average, turtles lay 110 eggs in a nest. The largest clutches are laid by hawksbills, which may lay over 200 eggs in a nest. Once the female completed the nesting, she never returns to it.
The nest's temperature determines the hatchling's gender. Warmer temperature produces mostly females, and cooler temperature produces a majority of males. (Another unfortunate side effect of global warming can be it's result on future population's gender rate.) Turtle eggs look like ping-pong balls, with a soft shell.
Mortality rates for turtle eggs are high due to predation by ghost crabs or humans. Some nests are laid to close to the tide line and if not relocated will be lost.
When the time comes and hatchlings break free from their shell inside the egg chamber, they stimulate the others to emerge from their eggs too. Once most hatchlings have emerged from their shells, they climb on top of each other and the discarded eggshells til they reach the top of the chamber. They emerge either en masse or in small groups, but emerging together increases the chance of survival. Sea turtles are attracted to light, therefore they are guided by the moonlight reflecting on the sea. As a result of light pollution (street lights, house & hotel lights) they may become victims of predators or accident. If hatchlings delay in emerging from the nest, the heat of the sun also may harm them. On the way to the sea
The dangers are not over, on their way to the sea, predators as crabs, birds, fish and sharks are waiting for them. If they survive all these, human caused threats as fishing gear (long line), ingestion of marine debris, boat strikes, trash on beaches and pollution also harms the population.
As a result, only one hatchling in a thousand make it to adulthood (15-25 yrs).
In Aldabra itself, crabs, crows and herons are waiting for the newly emerged hatchlings on the shore, and many blacktip reef sharks in the shallows. Only a very lucky few reach the open sea's "safety".
Source: Sea Turtle Conservancy
Photo: SIF Aldabra FB page