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Caretta caretta
Status Threatened
Listed July 28, 1978
Class Reptilia
Order Testudines
Family Cheloniidae (Sea Turtle)
Range Oceanic
Region 4 Florida, Georgia, North Carolina, South Carolina
The loggerhead turtle (Caretta caretta) is a threatened species under the U.S. Endangered Species Act. It is also listed as threatened by the state of South Carolina and is our state reptile. The numbers of loggerhead nests deposited on beaches in South Carolina have declined significantly during the last two decades. Because loggerhead turtles require more than 20 years to reach maturity, recovery of the population depends to a great extent on the survival of breeding age animals from one nesting season to the next
Description
The loggerhead is a large sea turtle, weighing as much as 227 kilograms at maturity. The reddish brown carapace (shell) is oval, up to 114 centimeters long, and divided into five or more shields that in juveniles sometimes overlap. The broad, scaly head is yellowish to olive brown. Limbs are modified as flippers. In the Atlantic Ocean population, the front flippers possess two claws.
Behavior
Loggerheads are primarily carnivores, feeding on large variety of oceanic creatures, including mollusks, sponges, and horseshoe crabs. The turtle's powerful jaws are adapted for crushing hard-shelled mollusks. Raccoons, lizards and dogs prey on the eggs, while many species of birds feed on hatchlings as they make their way to the sea.The life cycle consists of a brief terrestrial stage when eggs are deposited on beaches and hatch, and a pelagic stage that begins when hatchlings return to the ocean. The nesting of the loggerhead is seasonal and generally takes place from late spring to summer - for instance, from May to August in Florida and South Carolina in the United States, and from November to January in Tongaland, South Africa. From May through August, adult females appear on the nesting beaches. There they lay an average of two clutches of eggs at 13-day intervals. Each clutch contains about 120 eggs. The eggs incubate for two month. Then hatchlings emerge as a group, usually during the night, and make their way to the water and eventually to the open ocean. When they reach sexual maturity - when the shell is longer than about 50 centimeters females return to shore to lay their eggs, often migrating long distances. Mature females return to the same "home" beaches at two- or three-year
intervals.
Habitat
This ocean dwelling turtle requires well-drained dunes, clean sand, and grassy vegetation for nesting. Nestling beaches should be relatively undisturbed by humans or by predators. Stable temperatures and moisture are required for at least 60 days so that eggs can develop properly. In the ocean, loggerheads migrate, following vegetation-laden ocean currents.
Historic Range
The loggerhead turtle is widely distributed throughout the world's temperate and subtropic oceans with Atlantic, Mediterranean, and Pacific populations. The largest population in the world nests on the beaches of the Sultanate of Oman and numbers about 30,000 individuals. The Fish and Wildlife Service (FWS) is primarily concerned with the stock that nests on the eastern seaboard of the U.S. and in the Greater Antilles.
Current Distribution
The loggerhead nesting population of the U.S. is thought to number about 15,000 individuals each year, 90 percent of the nesting occurs in Florida.
Conservation and Recovery
Like most other marine turtles, the loggerhead's historic nesting beaches have suffered degradation from residential and recreational coastal development, dune stabilization, beach sand mining, and erosion. The profusion of beachfront lighting tends to disorient hatchlings, causing them to move toward the lights rather than toward the sea. Predation of eggs by raccoons and dogs has been identified as a serious problem on some beaches.
Many organizations, universities, and wildlife agencies are working together to protect and rehabilitate nesting habitat. For example, the National Park Service, Merritt Island National Wildlife Refuge, and the Air Force are cooperating to protect 68 kilometers of nesting beaches at Cape Canaveral, Florida. Their predation control efforts have resulted in successful hatching of 60 percent of nearly 5,000 clutches deposited annually there.
In South Carolina, efforts to protect habitat are underway at Cape Island. Turtle nests are fenced to prevent predation or human disturbance. Clutches are relocated from eroding beaches.
At sea, the loggerhead turtle is incidentally trapped in the trawling nets of commercial shrimp fishermen. Recently, the National Marine Fisheries Service (NMFS) has developed regulations that require large shrimp boats to use turtle excluder devices (TEDs), which are fitted at the mouth of shrimp nets.
Below is one of several migration monitoring maps developed by the South Carolina Department of Natural Resources and Sea Turtle Survival League. The loggerhead being monitored in this map has been named Virginia.
Updates courtesy of Sally Murphy, South Carolina Department of Natural Resources.
This map is updated with new points as soon as they are received by the Sea Turtle Survival League. The red location point is the most recent location received for this turtle. If the red point is more than two months old, then the transmitter is most likely no longer working.
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