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the Legacy continues…………………….
Gregory R. Mann, Ph.D. {ret.}

Loggerhead Sea Turtle

“Caretta caretta”

The Loggerhead Sea Turtle is the largest hard-shelled turtle in the world and is the largest of all turtles. The Loggerhead is named for its exceptionally large head. Loggerhead Sea Turtles are found in coastal tropical and subtropical waters often extending to temperate waters in search of food. Found in the Atlantic Ocean from Argentina to Nova Scotia. The highest populations in North America are found on barrier islands from North Carolina to the Florida Keys. The Loggerheads migrate to the Bahamas in the winter. Small populations of the Atlantic Loggerhead are also found on barrier islands off of the Texas coast. Primary habitat is in southeastern United States ranging southward to South America and extending eastward to Africa and the Mediterranean as well as areas of the western Pacific and Indian Oceans. Hatchling habitat is primarily in warm ocean currents among flotsam such as Sargasso mats. Adult habitat includes rock outcroppings and reefs near shore as well as in brackish lagoons and the mouths of inlets. Long migrations often occur, especially to return to nesting beaches. Primarily carnivorous during most of their lives. Hatchlings often eat sponges, sea jellies, Sargasso weed, small gastropods crustaceans. Juveniles, sub-adults and adults feed upon Conch, Clams, Horseshoe Crabs as well as other crustaceans.

They have powerful jaws that enable them to easily crush the hard shells of their prey. During migration through the open sea, Loggerhead Sea Turtles eat sea jellies, pteropods, floating mollusks, floating egg clusters, squids and flying fishes. Nesting can take between 1 and 3 hours. After a female Loggerhead Sea Turtle drags herself up the beach, she hollows out a pit with her back legs and deposits from 50 to 200 eggs the size of golf balls. When the last egg is laid, the turtle covers the eggs with sand, tamps down the sand with her plastron and flings more sand about with her flippers to erase any signs of the nest. After about 2 months, the hatchling Loggerhead Sea Turtles emerge at night. The light reflected off the water from the sky guides them to the sea. These days, car headlights, street lamps or lights on buildings near the beach cause some hatchlings to travel in the wrong direction. Waiting birds make fast meals of other hatchlings. Any babies still on the beach in the morning are easily picked off by predators or die in the hot sun. It is thought that when the surviving hatchlings reach maturity, they return to the beach where they hatched to lay their eggs. Loggerhead Sea Turtles reach sexual maturity when adults and their shells are longer than 90 cm in length and thought to occur when they are from 12-30 years of age. In the United States, the southeastern region from North Carolina to Florida hosts the majority of the nesting. In Florida, Brevard County beaches receive the most nesting females per year than generally any other county in Florida. Nesting also occurs in some areas of the northeastern coasts of Mexico and minor beaches in the Caribbean. In the Mediterranean nesting is reported in Greece, Turkey, Israel as well as Italy. The Indian Ocean’s major nesting sites are in South Africa as well as large nesting colonies on the Arabian Peninsula on Masirah Island, Sultanate of Oman.

Nesting occurs during late spring and summer. Females re-nest approximately every two weeks during the nesting season laying between two and fives times a season with an average clutch size of 100 eggs. Egg diameter is from 34.7-55.2 millimeters. Incubation period varies, but 49 days at the least and 69 days at the most dependent upon the location of nesting. Sex determination is dependent upon the incubation temperature, therefore there is an optimal incubation temperature that ranges between 26 °C to 32 °C. The male sex is determined at cooler temperatures. Nests are often lost to predators such as raccoon, dogs, ghost crabs, seabirds and ants as well as to shoreline erosion and human predation. Hatchlings are preyed upon by mammals, seabirds, crabs and carnivorous fishes. Predation continues to be high until the Loggerhead Sea Turtles are big enough to avoid being swallowed by large carnivorous fishes such as Groupers, Snappers and Jacks. Sharks are a formidable predator throughout the life cycle of Loggerhead Sea Turtles, although larger turtles can often avoid a shark attack by presenting the flat side of the plastron or carapace to prevent biting. Their life expectancy is at least 30 years and up to 50 years or more. 

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