Loggerhead Sea Turtle

  Loggerhead Sea Turtle 

Loggerhead sea turtle is a species of oceanic turtle belongs to the family Cheloniidae. This marine reptile gets its name for its massive head and strong jaw. This hard-shelled turtle is the largest sea turtle species of all hard-shelled turtles. The scientific name of is Caretta caretta. The loggerhead sea turtles evolved around 110 million years ago. In 1988, South Carolina named the loggerhead sea turtle (Carreta carreta) as the official state reptile and it is also the state saltwater reptile of Florida. 

Description of Loggerhead Sea Turtle 

Loggerhead sea turtle is the second largest turtle species after Leatherback sea turtle. Adult loggerhead sea turtle’s weight is around 75kg and the length of its carapace is 80cm to 110cm. Color of its carapace is reddish-brown and the plastron is light yellow. The upper side of the loggerhead sea turtle’s neck is brown in color but the bottom is yellow. Light and dark lines of star shapes may be present on the carapace. On the middle of the carapace, five scutes run down vertically and the five pairs of costal scutes run down both side of vertical middle scutes. Its carapace acts as an armor and protects the turtle but the turtle cannot withdraw its head or flippers inside its carapace. Male has longer tail and claws than the female but the plastron is shorter. Their front flippers are larger than hind flippers and approximately half the length of their carapace. 

As the loggerhead sea turtle is a reptile so their kidneys cannot excrete large volume of salt via urine. They have special lachrymal glands which are located in the corner of each eyes. These glands remove the excess salt which gives an appearance of tears. This glandular secretion also protects the female turtle’s eyes from the sand when it digging the sand to make nest. The salty solution or glandular secretion also helps to keep the female turtle’s eyes moist when they spent their time on the beach for making their nests.  

Where Do Loggerhead Sea Turtles Live? 

The Loggerhead turtles is a wide-ranging species. Loggerhead turtles live all over the temperate subtropical and tropical regions of the Atlantic Oceans, Pacific Oceans and Indian Oceans and also in the Mediterranean Sea. They live in open oceans and in shallow coastal waters. 

Loggerhead turtles live in sea or in inshore waters like salt marshes, lagoons, bays, ship channels and also in rocky place and coral reefs where they get plenty of preys. 

 In the Atlantic Ocean, Loggerhead turtles are found in along the south-eastern coast of North America and in the Gulf of Mexico and their range extends from Newfoundland to Argentina. Along the European and African coastlines, a few Loggerhead turtles are found. Florida is one of the major nesting sites of Loggerhead turtles, where the loggerhead turtles built over 67,000 nests per year. 

Their nesting is found in Virginia, Brazil and Cape Verde Islands. On the eastern side of the Atlantic, their significant nesting site is found only on the Cape Verde Islands. In Atlantic, the Loggerhead turtle’s range extends from Canada to Brazil. In Pacific Ocean, Loggerhead turtles live in temperate to tropical regions. In the Eastern Pacific, Loggerhead turtles are found from Alaska to Chile. East China Sea, Baja California Peninsula are rich feeding grounds for juvenile turtles. In US, they are occasionally found from the coast of Washington and Oregon. In Pacific Ocean, the major nesting areas are Eastern Australia and Japan and also Great Barrier Reef. Three most important nesting grounds are found in Yakushima Islands, where 40% of all leatherhead turtles visited. A study suggests that 95% of Loggerhead turtle population along the coast of Americas hatch on Japanese Islands. 

Most loggerhead nesting are found in the western rims of Atlantic Ocean and Indian Ocean, mainly in Oman, Australia, US and also occur on the beaches from North California through south west Florida; a few nesting extends westward into Gulf of Mexico to Texas and also southern Virginia. 

 In the Indian Ocean, Loggerhead turtles are found to feed along the coastline of Africa, the Arabian Peninsula and in the Arabian Sea. In African coastline, they are found from Mozambique’s Bazaruto Archipelago to St Lucia estuary. Their major nesting site Oman, with 15000 nests, making the site the second largest nesting population of Loggerhead in the world. Western Australia is another main nesting ground. 

What Do Loggerhead Turtles Eat? 

Loggerhead Turtles are mainly carnivores. They have strong jaws that help them to crush the conches, bivalves, horseshoe crabs and other hard-shelled preys, which are their favourite food items. They also catch jellyfish, shrimps, fish, sponges etc. to eat. Although, sometimes the loggerhead turtles eat seaweed and sargassum. 

Most researchers believe that sea turtles have a strong sense of smell. They noticed that hatchlings reacted to the smell of shrimp. This adaptation helps sea turtles detect food in the ocean water. 

Reproduction of Loggerhead Sea Turtle 

Loggerhead sea turtle becomes sexually mature at the age of 34 to 35 years. Male loggerhead sea turtles show their courtship by nuzzling, biting and head or flipper movements. Loggerhead sea turtles mate in shallow coastal waters every 2 to 3

years. One single female usually mate with many male turtles. In the Northern Hemisphere, their mating season is from late March to early June and nesting season occurs between May and August but in the Southern Hemisphere, nesting season occurs between October and March. Male leatherback turtles never leave the water but female turtles nest on land. Female loggerhead turtles reach the beach where once they were born, which is called “natal homing”. They use the magnetic field of the Earth to differentiate their global position by latitude and longitude. They use their internal compass to return to the specific location again. Another possibility is that a distinctive smell of their home beach, helps them to reach their natal beach or birth beach. 

After reaching its home beach, female loggerhead sea turtle first clears the area of any debris with her front flippers and throws sand backward and dig a pit by using its hind flippers.  Every two weeks, female turtle emerge onto the beach at night and lays two to five clutches of up to 130 eggs. 

After laying eggs, she fills the hole with sand by using their flipper, now it leaves the nesting ground. After incubate for around 80 days the eggs start to hatch. The temperature in the nest affects the sex-determination. The temperature of the nesting sites is above 30° Celsius favor the development of females and below 30° Celsius produce males. The hatchlings are about 4.6cm long and weight can be 20gm and range in color is from light brown to almost black. 

Threat to The Loggerhead Sea Turtle 

Loggerhead sea turtle population have reduced in the past few decades due to human’s demand for their meat, skin, eggs and shells, bycatch in commercial fishing gear, illegal trade, consumption, and climate change. Turtle eggs are a common food in Mexico. In 1978, under the Endangered Species Act, Loggerhead sea turtles were classified as threatened species. As loggerhead turtles are highly migratory, primary threat to sea turtles is accidental capture in fishing gear, primarily in trawls, longlines, and gillnets, hook and line of the world's fisheries, resulting in drowning or cause injuries that lead to death or debilitation.  

Vehicle traffic on beaches, uncontrolled coastal development and other human activities are the major causes of damage and destruction of sea turtle nesting beaches worldwide. Vehicle traffic on the beaches makes the sand harder which make it impossible for female leatherback turtles to dig nests.  

Hatchlings disoriented by lights from roads and buildings may not reach the water after emerging from their nests. Per year tens of thousands of hatchlings die due to artificial lights. 

 When loggerhead turtles are at or near the surface, various types of watercraft can collide with them, resulting in injury or death.  

Water pollution is one of the major threats to loggerhead sea turtles. They mistakenly eat fishing line, plastic bags and other plastic debris, floating oil and other materials discarded by humans which can cause their death. 

Loggerhead sea turtles face various dangers at every stage of their lives and only one out of a thousand leatherback hatchlings survive to adulthood. When the hatchlings start their journey from the nest to the sea, they are killed and eaten by the crabs, toads, lizards, snakes, seabirds, other mammals and also humans. Adults are killed by large sharks, seals, and killer whales while flesh flies, feral dogs, and humans also attack the female turtles when they are on nesting ground. 

Why is the loggerhead sea turtle important? 

sand does not hold nutrients very well so very little vegetation grows on the dune. Female loggerhead sea turtles lay their eggs on beaches and the lower dunes. All the unhatched nests, eggs, egg shells and trapped hatchlings provide important nutrients to the dune vegetation which reduces soil erosion. Hatchlings of Loggerhead sea turtles are killed by crabs, land mammals, sea birds, toads, lizards, snakes, seabirds and the adults are killed by large sharks, seals, and killer whales so the turtles make an integral part of food webs both on land and at the ocean. When the loggerhead sea turtles migrate a long distance, they also transport many species like barnacles and other small crustaceans, remoras, algae, and diatoms. More than 100 species of animals and plants have been recorded surviving on a single logger turtle. 

They play an important role of coastal economies and native communities because have cultural significance and tourism value as the flow of visitors who come to admire the turtles is an important source of income. 

How many loggerhead sea turtles are left? 

Loggerhead turtles are endangered species and listed this species under the Endangered Species Act. A recent estimate show that there are more than 60,000 nesting female loggerheads. the southeast USA is the second most important nesting region where 5,000 to 15,000 female loggerhead turtles nest annually. 

How big do loggerhead sea turtles get? 

Loggerhead sea turtle is the second largest turtle species after Leatherback sea turtle. Adult loggerhead sea turtle’s weight is around 75kg and the length of its carapace is 80cm to 110cm. The hatchlings are about 4.6cm long and weight can be 20gm and range in color is from light brown to almost black.