Loggerhead Sea Turtle Fact Sheet
Loggerhead Sea Turtle
Caretta caretta
New York Status: ThreatenedFederal Status: Threatened
Description
The loggerhead sea turtle is perhaps the most common of the sea turtles and the only one that still regularly nests on the U. S. Atlantic Coast, on beaches from New Jersey to Texas. This reddish-brown turtle averages 3 feet (.9 m) in length and weighs 300 pounds (136 kg). Both the loggerhead sea turtle and the Atlantic ridley sea turtle have five or more large lateral plates on each side between the vertebral and marginal plates. The loggerhead sea turtle has two pairs of prefrontal plates on the conspicuously large, block-like head. The loggerhead sea turtle's powerful jaws are well suited to eating hard-shelled prey. It feeds on crabs and other crustaceans, mollusks, jellyfish and sometimes fish and eelgrass.
Life History
Most nesting occurs north of the Gulf of Mexico and Caribbean Sea in temperate waters, although some individuals nest in the western Caribbean. Loggerhead sea turtles also nest along the southeastern U. S. coast, with 90 percent of nests occurring in Florida. Females come out of the water to lay their eggs on beaches at night. An individual may nest up to 7 times in a single season, laying 100-125 eggs every 14+ days. The eggs hatch in 55-65 days; the hatchlings emerge at night to spend their first year among mats of sargassum weed and other flotsam. Sexual maturity is reached in 10-15 years, and the estimated maximum lifespan is 30 years.
Distribution and Habitat
Loggerhead sea turtles are found globally, preferring temperate and subtropical waters. In the western Atlantic, they range from the Canadian Maritime Provinces south to Argentina. Within its range, this species inhabits warm waters on continental shelves and areas among islands. Estuaries, coastal streams and salt marshes are preferred habitats.
Status
Loggerhead sea turtles and eggs are hunted extensively in many parts of the world. In the U. S., however, the main threat is from raccoons and wild boar which eat the eggs. On some nesting beaches, raccoons may destroy more than 95 percent of the nests. Encroaching human populations are also a threat. In Florida, almost the entire coastline is developed, under development, or subject to development. The introduction of exotic vegetation by humans may form dense root mats along shores, inhibiting egg-laying and trapping hatchlings. Beds of sargassum weed, where the early part of the life cycle is spent, accumulate pollutants such as oils, styrofoam and other plastics.
Management and Research Needs
Since 1978, the Endangered Species Act has prohibited commercial exploitation of loggerhead sea turtles in the U. S. Exploitation still occurs in other places around the world.
In order to aid turtles that may become stranded during migrations in the summer months, a Stranding Network was established in 1980 through the cooperation of the New York Department of Environmental Conservation, National Marine Fisheries Service and the Riverhead Foundation. Through this system, Riverhead is notified of strandings through a telephone number (631-369-9829). Marine biologists there handle stranded and dead specimens to collect biological information.
In response to sea turtle mortality in trawl nets, the U. S. Fish and Wildlife Service has issued regulations requiring shrimp trawlers of the southeastern and Gulf coasts to have a turtle excluder device (TED) on their nets. This device allows turtles and other large marine life to escape should they enter a net.
Additional References
Bjorndal, K. A., Ed. 1981. Biology and Conservation of Sea Turtles. Smithsonian Institution Press, Washington, DC
Carr, A. 1953. Handbook of Turtles. Cornell University Press, Ithaca and London.
Conant, R. and J. T. Collins. 1998. A Field Guide to Reptiles and Amphibians of Eastern and Central North America. Third Edition Expanded. Houghton Mifflin Co., Boston.
Hopkins, S. R. and J. Richardson. 1984. Recovery Plan for Marine Turtles. National Marine Fisheries Service.
Sternberg, J. 1981. Sea Turtles. Center for Environmental Education, Washington, DC
Drawing by Carol Decker
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