Loggerhead Turtle

At hatching, the newborns measure on average 45 mm with a weight of about 20 g. Adults measure between 90 and 115 cm and weigh between 120 and 160 kg, but much larger and heavier specimens have been recorded. Males are larger than females and, once fully grown, the male's tail extends more than 20 cm beyond the back of its shell. The longevity of the Loggerhead sea turtle is estimated to be over 65 years.

It has a very wide area of distribution and is found in both temperate and subtropical parts of the Atlantic, Indian and Pacific oceans, as well as in the Mediterranean sea.  It is the most geographically widespread of all sea turtles in terms of distribution and nesting. It is the only one that  lays its eggs in temperate zones.

Due to its migratory lifestyle, the Loggerhead turtle lives in a wide variety of habitats.  It travels thousands of km between feeding, mating and egg-laying areas.  The hatchlings' early years are called their ghost years because there is little data on how they live and move. They drift with the currents and use floating objects for shelter, adopting a pelagic (open sea) feeding behaviour. After several years spent offshore, they move closer to the coast, become loyal to a spawning site and adopt a benthic (seabed) feeding behaviour.

The sea turtle lives all its life in the water except for the female, which goes up on the beach during the nesting period to lay its eggs above the high tide line.  At night or very early in the morning, she digs a nest in the sand using its hind legs.  She lays between 70 and 100 eggs, depending on her size, which she then covers with sand before returning to the water.  She can repeat this scenario up to 7 times in one laying season but after that she will not lay eggs for 2 or 3 years.  Although protected by the sand, the eggs can be heavily preyed upon by dogs, insects, etc.  Hatching takes place about 60 days after laying, depending on the incubation temperature.  It often takes place at sunset or during the night. The climb out of the nest can last between 24 and 48 hours, with the collective movement facilitating the ascent, i.e. the emergence.  This laborious journey allows the hatchlings to build up strength in their flippers, giving them a better chance of making it to the water quickly.  Indeed, during the race to the sea, the hatchlings are particularly vulnerable, often falling prey to crabs, stray dogs, birds, etc.  The waves propel the young turtles out to sea where other numerous marine predators further reduce their chances of survival. It is estimated that only one in a thousand hatchlings will reach sexual maturity.

The Loggerhead sea turtle is omnivorous.  During the first two weeks of their life at sea, hatchlings draw on what remains of their yolk reserves (nutritional reserves). Carried by the currents, they feed on jellyfish and small crustacean larvae. During migration and, therefore, in the open sea, the adult turtle feeds mainly on jellyfish and squid. When it is near the coast, it feeds on bivalves, crabs, sea urchins and fish on the seabed.

Eggs and young turtles fall victim to a huge number of predators. But once the turtles reach adulthood, their large size and shell protect them from marine predators. The main predators of the adult turtle are the killer whale and the great white shark.

Because turtles are migratory, the threats to them are cumulative, including accidental capture in fishing nets, intense poaching of eggs and adults, development of tourist infrastructure and industrial fishing in the vicinity of egg-laying sites, pollution from hydrocarbons and heavy metals , ingesting plastic bags,which they mistake for jellyfish, etc.  

Equip fishing trawlers with turtle excluder devices.  This system reduces their mortality by providing an escape route out of the net.

Strengthen the protection of egg-laying areas from predators and tourist activities.

Improve recycling, recovery and management of waste to prevent it from ending up at sea...

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