Thursday, November 13, 2008

Turtles behaving naturally!

Nesting Hawksbill turtle, photo Elke Talma

People always get excited when you tell them you have seen a nesting turtle, but few seem to realise what a long and laborious process the poor turtle has to endure to make sure her eggs are safely buried on the beach. A successful nesting emergence can last anything from 1 hour to 3 hours, and in some cases for as long as 5 hours if a tenacious turtle is having trouble finding the perfect spot for her eggs.

Below is a brief description of what a turtle goes through to ensure the next generation of turtles.

Hawksbill turtle emerging from the sea, photo Elke Talma

Emergence: a female turtle will check the beach from the water before slowly emerging from the sea. She crawls slowly up the beach towards the vegetation, stopping repeatedly and looking for signs of danger.

IMPORTANT: If disturbed by movement or noise, she will return to the water, so FREEZE! Do not move until you are out of her line of sight.

Hawksbill turtle digging a body pit, photo Elke Talma

Digging the body pit: once she is within or near the vegetation line, and well above the high tide mark, the turtle will use her front flippers simultaneously to clear away any debris and loose sand. She may also use her hind flippers in sideways movements for clearing.

IMPORTANT: If disturbed by movement or noise, she will return to the water, so do NOT approach.

Hawksbill turtle digging an egg chamber, photo Elke Talma

Digging the egg chamber: using her rear flippers only, she will dig a hole approximately 30 to 50cm deep. She does this by alternately scooping sand out of the hole and throwing it aside. If she encounters roots, rocks or hard ground she may move to another site to dig again.

Once she can no longer reach loose sand in the hole, she will place both flippers on either side of the hole and take a short rest.

IMPORTANT: If disturbed by movement or noise, she will return to the water, so do NOT approach.

Hawksbill turtle laying a clutch of eggs, photo Ellen Waldrop

Laying: she positions her tail over the hole and starts depositing eggs in the egg chamber. She will lay 100 to 200 eggs in total in batches of 1 to 5 eggs at a time, tensing her body each time she drops her eggs.

During laying, she appears to go in a trance.

IMPORTANT: Wait a few minutes for her to settle in a rhythm. The turtle can be approached with caution, but approach from behind if possible, do NOT make noise and move slowly.

Hawksbill turtle covering the egg chamber, photo Elke Talma

Covering the egg chamber: after laying, the turtle uses her hind flippers to cover her eggs with sand. She will use her tail to gauge her progress. Once she touches sand, still using her rear flippers, she will then press down on top of the filled egg chamber, compacting the sand. This ensures that the egg chamber does not collapse when the hatchlings emerge in 2 months time , thus leaving an air space for them as they crawl through the sand to reach the surface.

IMPORTANT: The turtle can be approached with caution, but approach from behind if possible, do NOT make noise and move slowly.

Hawksbill turtle camouflaging her nest, photo Elke Talma

Camouflaging: once she has covered the egg chamber, the turtle starts to camouflage the nest area. She will throw loose sand over the nest site with her front flippers and may use her rear flippers to push sand over the nest area and move forward or backward to hide the location of the egg chamber.

IMPORTANT: While the turtle can be approached with caution, its recommend that you keep your distance… unless you want a face full of sand!

Hawksbill exiting the nesting beach, photo Elke Talma

Exit beach: once camouflaging is complete, the turtle will turn around to face the sea. She will rapidly crawl, down the beach, usually in a straight line, until she reaches the water.

If she is tired or unstressed by the nesting process, she may stop every now and again to rest, giving you the perfect opportunity for a photo.

If she is stressed and feels threatened, she is not stopping for hell or high water!

IMPORTANT: do not block her passage back to the sea, or she may not come back this beach to nest again!

In about 2 weeks time she should come back to the same beach to repeat the whole process again. In a season, a Hawksbill turtle will lay 4 to 5 clutches of eggs before returning to her feeding grounds.

1 comment:

patricia said...

A really nice blog . Clearly explaining how to behave when encoutering a turtle on the beach. Great photos. from Patricia