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Sea Turtles are made up of any of the marine turtles in the families Dermochelyidae (leatherback) and Cheloniidae (green, loggerhead, hawksfill and ridley). Though there are differences between the species, all act, swim and reproduce in the same manner.

Turtles are the oldest living group of reptiles, dating back to the time of the earliest dinosaurs. Due to abused fishing rights in the 19th and 20th centuries, sea turtle populations have greatly diminished.

This is the largest of all living turtles, measuring 7 feet in length and weighing upwards of 1,200 pounds. The leatherback turtle has no visible shell, though one is present. Bones buried deep in their dark brown and blackish skin serve as their shell. Leatherbacks are strong swimmers, omnivorous in nature and inhabit open seas worldwide.

This turtle got it's name for the greenish color of its fat. The green turtle is a large reptile. Its shell alone measures 3 feet in length and often weighs more than 250 pounds. The upper shell of the green turtle is smooth and marked by brown and slightly green hues. This turtle is most often found in warm, coastal waters through out the world, and distinguishes itself from others by leaving the water and basking in the sun.

The loggerhead is similar in size and weight to the green turtle, but has a relatively larger head. It is most often brown in color, and found in waterways worldwide. The most unfriendly of all sea turtles, the loggerhead is known for it's reportedly bad disposition.

This small sea turtle's name derived from the shape of its hooked jaws. Found in warm waters, this sea turtle is an aggressive reptile that feeds on both plant and animal matter.

Bearing wide, round shells, the ridleys live mainly in the Atlantic Ocean. Gray in color, ridleys are believed to have evolved through inner breeding of the green and loggerhead species. and are difficult to identify. Ridleys feed on both animals and plants and are commonly found on the East Coast in cooler water.

Sea turtles differentiate themselves from other turtles by several different factors. Unlike land turtles, sea turtles are unable to pull their heads or flippers into their shells for protection. Land turtles have feet and claws, which enable them to walk, sea turtles do not. Sea turtles posses paddle-like flippers and only two claws, which are designed and used for swimming and breeding purposes. Land turtles often carry flat shells. Sea turtles live in a dome shaped shell. Sea turtles also have specially designed lungs, which allow them to efficiently take in and store oxygen, which land turtles do not have.

For most species, there is a period of courtship that takes place, lasting several weeks. Two or more males often court a single female. Male sea turtles house enlarged claws on their front flippers, which aid them in grasping the shell of the female during mating season. Fertilization of the female is internal and copulation takes place just offshore.

Like all reptiles, sea turtles lay eggs. After reaching the age of two, the female sea turtle breeds every 10-15 days during the warmest months of the year, returning to the sea in between sessions. The female often comes ashore alone at night during high tide to dig a nest with her front flippers. During one breeding season, each female will dig up to 7 nests, laying 50-200 Ping Pong ball sized eggs at each location. Once the eggs have been dropped, the female works to cover the hole to keep the eggs safe and prevent them from drying out. The female sea turtle will spend two or more hours out of the water during the nesting process.

The sex of baby turtles in temperature-dependent. Warmer water temperatures generally produce female turtles and likewise, colder temperature will produce male turtles. When the temperature is at an in between level, nature decides.

Though incubation periods vary between the species, most require 45-70 days.

Hatchlings use a caruncle (temporary tooth) to help break open the shell. After hatching, the young turtles will take 3-7 days to dig their way to the surface. Once they've emerged from the nest, they head toward the light of the ocean, being careful to avoid predators.

Hatchlings are rarely seen during the first year of life. Taking great care to camouflage themselves, young turtles remain with 10 miles of land for their first year, where they learn to hunt and gather food as a unit.

The diet of sea turtles varies greatly from species to species. Some turtles are carnivorous, some are herbivorous and others are omnivorous. Their jaw structures generally indicate species diet patterns.

All sea turtle species in the United States have been listed as threatened or endangered since 1973. As a result of their endangered status, many countries have banned the import or export of sea turtle products. It is also illegal to kill an adult sea turtle or collect their eggs.

As an added precaution, many shrimp fishermen have adapted their techniques and redesigned fishing equipment to help prevent turtles from being caught in shrimp nets.

Once sea turtles reach sexual maturity, they have an estimated reproductive life of 30 years. This means that most sea turtles have an average lifespan of 80 years.