Species of Sea Turtles on Alabama’s Beaches

LoggerheadLoggerhead: Caretta caretta

Loggerhead sea turtles have large heads and blunt, powerful jaws. The turtle’s carapace and flippers are reddish-brown in color and the plastron is yellow. These nesting neighbors can grow to an average weight of 200 pounds and an average length of three feet. Although sea turtles are subject to predation throughout their life cycle, predation is particularly high during the first two years of life. Highest predation occurs during incubation and during the race of the hatchlings to the sea. The eggs are eaten by ghost crabs, raccoons, skunks, foxes, and dogs. Hatchlings are preyed upon by mammals, sea birds, crabs, and carnivorous fishes. Predation continues to be high until the 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 sea turtles, although larger turtles can often avoid a shark attack by presenting the flat side of the plastron or carapace to prevent biting.

Date of Listing: Threatened, July 28, 1978. However, on Sept. 11, 2011, the listing was revised from a single global threatened species to a listing of nine Distinct Population Segments (DPS).

Reason for Concern: There are numerous reasons for concern, including the loss of nesting habitats due to coastal development, nest predation and marine pollution. In addition, hatchlings become disoriented by beachfront lighting, preventing them from reaching the water. Strikes from watercraft is also a cause for concern. Because of their feeding behavior and their habit of wintering in shallow waters, Loggerheads, along with Kemp’s Ridley Sea Turtles, are more likely to be caught in large shrimp trawl nets and drown. Today, Turtle Excluder Devices (TED’s) pulled by shrimp boats help reduce mortality from net entanglement by allowing many turtles to escape from the nets.

Size: Adults weigh 170 to 500 lbs. and have a carapace up to 45 inches in length.

Diet: Although feeding behavior may change with age, this species is carnivorous throughout its life. Loggerheads eat small sea animals, including mollusks, crustaceans and fish. During migration through the open sea, Loggerheads eat jellyfish, pteropods, floating mollusks, floating egg clusters, squids and flying fish.

Habitat (where it lives): Loggerheads are capable of living in a variety of environments. They can be found hundreds of miles offshore or in inshore areas including bays, lagoons, salt marshes and even creeks. Eighty-eight nesting beaches make up the loggerhead’s terrestrial critical habitat. These includes beaches in Alabama, Mississippi, Georgia, Florida, South Carolina and North Carolina.

Life Span: Thirty to 50 years or more.

Reproduction: As with other sea turtles, females return to lay their eggs on or near the same beach where they hatched. Unlike other sea turtles, courtship and mating usually do not take place near the nesting beach, but rather along the migration routes between feeding and breeding grounds. Females may nest one to seven times during a breeding season (April to September in the U.S.) at intervals of about 14 days, laying as many as 126 soft, round white eggs per nest along the southeastern U.S. coast. The eggs incubate in the sand for 42 to 75 days. Hatchlings emerge from the nest primarily at night. After the majority of the hatchlings appear at the surface of the nest, they start a frenzied race toward the surf and out to sea. The loggerheads age of sexual maturity is believed to be between 32 to 35 years of age.

Population Numbers: Most reliable counts are of documented nests. Total estimated nesting in the U.S. fluctuated between 47,000-90,000 nests annually over the past two decades.

Interesting Fact: Loggerhead hatchlings and juveniles are frequently associated with sea fronts (areas where ocean currents converge), downwellings, and eddies, where floating open ocean animals gather. The time that young turtles remain in these places feeding and growing is called the “lost year.” During this period, young turtles float on rafts of seaweed with the currents, feeding on organisms associated with sargassum mats.

KeKempsSeaTurtlemps Ridley: Lepidochelys kempii

Female turtles lay the majority of their eggs on beaches along the east coast of Mexico. It is the only known major nesting beach in the world for this turtle. Females nest in large groups called “arribazones.” Groups of females move onto the beach to lay their eggs over a period of a few days. Each turtle digs a hole in the sand, deposits her eggs and returns to the sea. In 50 to 55 days, the eggs hatch and the baby turtles (hatchlings) rush to the water and out to sea. After at least 10 years at sea, adult females return to nest at the same beach where they hatched. Male turtles never leave the water. They appear in waters near the nesting beach during the breeding season to mate with the females.

Date of Listing: Endangered, Dec. 2, 1970

Reason for Concern: Kemp’s Ridley sea turtles are endangered primarily because of human activities, including harvesting of adults and eggs, as well as incidental capture in commercial fishing operations.

Size: Adults reach 24 inches in length and weigh up to 100 pounds

Diet: Mostly crabs; also shrimp, snails, clams, jellyfish, sea stars, fish

Habitat (where it lives): Adults inhabit nearshore and inshore waters of the northern Gulf of Mexico that contain muddy of sandy bottoms where prey is found. However, hatchlings and small juveniles swim to the open ocean where they drift with floating Sargassum seaweed. This can last up to two years, or until the turtles reach a carapace length of approximately eight inches.

Life Span: Individuals surviving to adulthood may live 30 years and possibly up to 50 years.

Reproduction: Kemp’s Ridley sea turtles nest from April to July. Females nest primarily during daylight hours and the clutch size averages 100 soft, white eggs. Some females nest 2.5 times a season at 14 to 28-day intervals. This turtle reaches sexual maturity at about 12 years.

Population Numbers: Most reliable counts are of documented nests. In 1985, there were only 702 nests reported. However, that number has risen significantly. In 2011, 20,570 nests were reported in Mexico and 199 nests were recorded in the U.S., primarily in Texas.

Interesting Fact: Scientists think baby sea turtles may remember or “imprint” on the particular smell, chemical make-up, or magnetic location of the beach where they hatched.

GreenSeaTurtleGreen: Chelonia mydas

While adult green sea turtles have a smooth, keelless carapace with dark mottling, hatchlings have a black carapace, white plastron and white margins on the shells and limbs. Green sea turtles have a worldwide distribution, primarily in tropical and subtropical waters, including the Atlantic, Pacific and Indian Oceans. During the day, Green sea turtles feed in the sea grass beds that grow in shallow waters. At night, they sleep on the shallow bottom and sometimes out of the water on rocky ledges. Although sea turtles are subject to predation throughout their life cycle, predation is particularly high during the first two years of life. The eggs are eaten by raccoons, skunks, opossums, mongooses, coatis and dogs. Hatchlings are preyed upon by mammals, sea birds, crabs and carnivorous fish. Predation continues to be high until the turtles are big enough to avoid being swallowed. Sharks are a formidable predator throughout the life cycle of the Green Sea Turtle.

Date of Listing: Threatened, July 28, 1978

Reason for Concern: The meat and eggs of the Green Sea Turtle have long been a source of food for people. Although international trade of wild Green Sea Turtles is against the law, capturing turtles for local consumption still persists in many central Pacific Islands, Southeast Asia and Indonesia, Indian Ocean islands, east coasts of Africa and Arabian peninsula, in Central and South America, and in Mexico. Exploitation of the nesting grounds either by human interference or pollution poses the greatest threat to these turtles. In the past, Green Sea Turtles were often killed in large shrimp trawl nets. Today, Turtle Excluder Devices (TED’s) pulled by shrimp boats help reduce mortality from net entanglement.

Size: Maximum size of 4 feet in length, weighing up to 440 pounds.

Diet: Adults feeds mostly on sea grasses and algae, while hatchlings eat a variety of plants and animals, including sponges, crustaceans, sea urchins and mollusks.

Habitat (where it lives): Green Sea Turtles feed in shallow water areas with abundant sea grasses or algae. The turtles migrate from nesting areas to feeding grounds, which are sometimes several thousand miles away.

Life Span: At least 30 years and up to 50 years or more.

Reproduction: Adults reach sexual maturity between 25 to 50 years of age. Nocturnal nesting occurs at intervals of 2, 3 or 4 years. Incubation for eggs ranges from 45 to 75 days and clutch size varies from 75 to 200 eggs. Hatchlings emerge at night.

Population Numbers: It is estimated that 5,000 females nested in 2010 in Florida. In 2005, more than 10,000 females are estimated to have nested on beaches lining the Indian Ocean resulting in approximately 44,000 nests.

Interesting Fact: The color of the hatchlings, black above and white below, is probably an adaptation to life near the surface in the open ocean, making them less conspicuous to fish and bird predators.

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