Sea turtles are one of the Earth’s most ancient creatures. The seven species found today became distinct from all other turtles at least 110 million years ago. 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.
Size The Kemp’s Ridley is the smallest sea turtle at 30 inches long and weighing 80 to 100 pounds. The largest sea turtle is the leatherback - an adult can reach over six and a half feet long and weigh over 2,000 pounds. Adult female and male sea turtles are the same size.
Lifespan Up to 80 years.
Depends on the species. 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.
Sea turtles are found in warm and temperate waters throughout the world and migrate hundreds of miles between nesting and feeding grounds.
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. When females come to the shore they dig out a nest in the ground with their back flippers, lay eggs in it, cover it up and go back 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.
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.
Sea turtles are threatened by coastal development, direct take of turtles and eggs, pollution and pathogens global warming and fisheries impacts. Fisheries impacts are thought to be one of the leading causes for sea turtle death and injury worldwide and can occur when turtles bite baited hooks, become entangled in fishing lines, are crushed by dredges, or otherwise held underwater by a variety of fishing methods.
Source from http://www.defenders.org/