Loggerhead Sea Turtle

Caretta caretta is commonly called the "Loggerhead" sea turtle due to their overly large heads, which are comprised of a horny beak that is significantly thicker than in other sea turtles. This species is the largest hard-shelled turtle in the world. Loggerhead turtles have large heads (when compared to other species of marine turtles) and strong, muscular jaws (which help them crush prey such as crabs and lobsters).

The loggerhead sea turtle is a marine mammal that grows quite large. Adults of this species weigh from 170-500 pounds (77-227 kilograms) and are nearly four feet (1.2 meters) in total length. The upper shell or carapace is widest near the front, just behind the front flippers, and then tapers toward the rear. The carapace is colored reddish-brown with some yellowish touches; underneath, the plastron is creamy yellow. There are five pairs of costal shields or plates on each side of the central row of plates on the carapace. The shell margin of young loggerheads has a somewhat serrated appearance which disappears as the turtle matures. The limbs are paddle-shaped and each bears two claws. As with all sea turtles, the adult male has a long tail, but the tail of the female is short. Scales on the top and sides of the head and top of the flippers are also reddish-brown, but have yellow borders. The neck, shoulders and limb bases are dull brown on top and medium yellow on the sides and bottom. The plastron is also medium yellow. The average adult size is 92 cm straight carapace length; average weight is 115 kg. Hatchlings, on the other hand are dull brown in color. Average size at hatching is 45 mm long; average weight is 20 g. Maturity of the loggerhead sea turtle is reached at between 16-40 years.

The loggerhead sea turtle resides in the euphotic zone, where they are able to receive sufficient amounts of light. Adults and juveniles live in shallow waters of the continental shelves, often in water only a few tens of meters deep. They spend much of their time around reefs, or along the bottom. Adults sometimes travel, diving thousands of kilometers deep. Loggerhead sea turtles are usually found in coastal tropical and subtropical waters often extending to temperate waters in search of food. They are found in the Atlantic Ocean from Argentina to Nova Scotia. The highest populations of these sea turtles are in North America, and are found on barrier islands from North Carolina to the Florida Keys.

Loggerheads occupy three different ecosystems during their lives--the terrestrial zone, the oceanic zone, and the neritic zone. Loggerheads nest on ocean beaches, generally preferring relatively narrow and steeply sloped coarse-grained beaches. Immediately after hatchlings emerge from the nest, they begin a period of frenzied activity during which they move from their nest and swim away from land.

After this swim frenzy period, post-hatchling loggerheads take up residence in areas where surface waters converge to form local downwellings, where there is a buildup of floating material, such as seaweed, particularly sargassum mats. Post-hatchlings within this habitat are observed to be calm and tend to sit and wait to feed on a wide variety of floating items. As post-hatchlings, loggerheads may linger for months in waters just off the nesting beach or become transported by ocean currents within the Gulf of Mexico and North Atlantic.

Somewhere between the ages of 7 to 12 years, oceanic juveniles migrate to near shore coastal areas (neritic zone) and continue maturing until adulthood. In addition to providing critically important habitat for juveniles, the neritic zone also provides