Sea turtles are one of the Earth's most ancient creatures. The seven species that can be found today have been around for 110 million years, since the time of the dinosaurs. The sea turtle's shell, or "carapace" is streamlined for swimming through the water. Unlike other turtles, sea turtles cannot retract their legs and head into their shells. Their color varies between yellow, greenish and black depending on the species.
© James Dawson
What sea turtles eat depends on the subspecies, but some common items include jellyfish, seaweed, crabs, shrimp, sponges, snails, algae and mollusks.
It is difficult to find population numbers for sea turtles because male and juvenile sea turtles do not return to shore once they hatch and reach the ocean, which makes it hard to keep track of them.
Did You Know?
Green sea turtles can stay under water for as long as five hours even though the length of a feeding dive is usually five minutes or less. Their heart rate slows to conserve oxygen: nine minutes may elapse between heartbeats.
Sea turtles are found in all warm and temperate waters throughout the world and migrate hundreds of miles between nesting and feeding grounds. Most sea turtles undergo long migrations, some as far as 1400 miles, between their feeding grounds and the beaches where they nest.
Sea turtles spend most of their lives in the water, where not much information can be gathered on their behavior. Most of what is known about sea turtle behavior is obtained by observing hatchlings and females that leave the water to lay eggs. Sea turtles, like salmon, will return to the same nesting grounds at which they were born. When females come to the shore they dig out a nest in the ground with their back flippers, bury their clutch of eggs and return to the ocean. After hatching, the young may take as long as a week to dig themselves out of the nest. They emerge at night, move toward the ocean and remain there, solitary, until it is time to mate.
Temperature: Temperatures of the sand where the turtles nest determine the sex of the turtle: below 85 degrees Fahrenheit (30ºC) is predominately male; above 85 degrees Fahrenheit (30ºC) is predominately female.
Mating Season: March-October depending on the species.
Gestation: 6-10 weeks.
Clutch size: Between 70-190 eggs depending on the species.
When the young hatch out of their eggs, they make their way to the ocean. Few survive to adulthood.