Over the course of a nesting season, sea turtles will leave their homing ground and migrate to resting grounds to build a nest and lay eggs.
Courtship activity usually occurs several weeks before the nesting season. It can take place either on the surface or under water. Males may court a female by nuzzling her head or by gently biting the back of her neck, which a single female may court with two or more males. The fertilization is internal.
Female turtle would choose to lay eggs on sandy and quiet beaches at night. Most females return to the same beach each time they are ready to nest, moreover, they often emerge within a few hundred yards of where they last nested.
The female turtle crawls to a dry part of the beach and begins to flings away loose sand with her flippers. She then constructs an egg cavity using her cupped rear flippers as shovels. The egg cavity is shaped roughly like a tear drop. When the turtle has finished digging the egg chamber, she begins to lay eggs. The average size of a clutch ranges from about 80 to 120 eggs, depending on the species. The female then covers the nest with sand using her hind flippers. Nesting sea turtles appear to shed tears, but the turtle is just secreting salt that accumulates in her body.
Incubation takes about 60 days. Essentially, the hotter the sand surrounding the nest, the faster the embryos will develop. Cooler sand has a tendency to produce more males, with warmer sand producing a higher ratio of females. Hatchlings usually emerge from their nest at night. Once they decide to burst out, they erupt from the nest cavity as a group. The little turtles orient themselves to the brightest horizon, and then dash toward the sea.
Threats to Sea Turtle...
Sea turtles are beautiful, efficient animals that travel the world's oceans and know to return to the beach where they were born to lay their eggs. They have been in existence for millions of years and flourished until the last 100 years when they became endangered, mostly by human activities.
Major threats that have brought all species of sea tur-tles to the edge of extinction are:
• large-scale poaching of adult turtles for meat, shells and leather
• commercial exploitation of sea turtle eggs
• drowning of sea turtles in fishing nets
• development and destruction of nesting beaches
• pollution of the oceans
|Patong beach, Thailand, used to have thousands of hatching turtles every year, but it just the history. How can mother turtles find the places for their babies on this crowed beach?