Few people know that the leatherback turtle (lut) is emblazoned on all the official papers of the maritime department belonging to the Republic of Fiji. For the inhabitants of the archipelago, the sea turtle represents speed and excellent navigational skills.
Description of the leatherback sea turtle
The only modern species in the leatherback turtle family provides not only the largest but also the heaviest reptiles. The Dermochelys coriacea (leatherback turtle) weighs between 400 and 600 kg, rarely gaining twice that weight (900-plus kg).
The lute has a special shell structure: it consists of thick skin rather than horny plates like other sea turtles.
Appearance
The pseudocarapax of the leatherback turtle is represented by connective tissue (4 cm thick), over which there are thousands of small shields. The largest of them form 7 strong ridges, resembling tight ropes, stretching along the carapace from head to tail. Softness and some flexibility are also characteristic of the thoracic (not fully ossified) part of the tortoise shell equipped with five longitudinal ribs. Despite the lightness of the carapace, it reliably protects the lute from enemies, and also contributes to better maneuvering in the thick sea.
The head, neck, and limbs of juvenile tortoises display shields that disappear as they grow older (they only remain on the head). The older the animal is, the smoother its skin is. The turtle’s jaws have no teeth, but they have powerful and sharp horny edges on the outside, reinforced by the jaw muscles.
The leatherback tortoise’s head is quite large and is not able to retract under the shell. The front limbs are almost twice as large as the hind limbs, reaching a wavelength of 5 meters. On land, the leatherback turtle looks dark brown (almost black), but the main color background is diluted with light yellow spots.
Lifestyle of the lute
Were it not for their impressive size, the lute would not be so easy to spot – the reptiles do not bunch up in herds and behave like typical solitary individuals, cautious and secretive. Leatherback Turtles are timid, which is odd for their huge size and immense physical strength. Lutus, like other turtles, is rather clumsy on land, but beautiful and swift at sea. Its gigantic size and weight do not hinder it here: in water, the leatherback turtle swims quickly, maneuvers dashingly, dives deeply and stays there for a long time.
High speed (up to 35 km/h) is provided by the developed pectoral muscles and four limbs, similar to flippers. The back ones replace the rudder and the front ones work as a real engine. The leatherback turtle is reminiscent of a penguin – it seems to be floating in the water, smoothly rotating large front flippers.
Life span
All great turtles (thanks to their slow metabolism) live very long, and some species can live up to 300 years or more. Behind the wrinkled skin and sluggish movements can hide both a young and an elderly reptile, whose internal organs hardly change with time. In addition, turtles are able to go months or even years without food and drink (up to 2 years) and are able to stop and start their heart.
If it were not for predators, humans and infectious diseases, all turtles would live up to the age limit programmed in their genes. The lute is known to live about half a century in the wild, and slightly less (30-40) in captivity. Some scientists call another life span of the leatherback turtle – 100 years.
Habitat, habitat
The leatherback turtle lives in three oceans (Pacific, Atlantic and Indian), swimming up to the Mediterranean Sea, but it is not often seen. The lute was also seen in Russian (then Soviet) waters of the Far East, where 13 animals were found between 1936 and 1984. Biometric parameters of the tortoise are 240-314 kg in weight, 1.16-1.57 m in length and 0.77-1.12 m in width.
Important: As fishermen assure, the figure of 13 does not reflect the real picture: near the southern Kurils leatherback turtles are found much more often. Herpetologists believe that the reptiles are attracted here by the warm Soya Current.
Geographically these and more recent finds are distributed as follows:
Peter the Great Bay (Sea of Japan) – 5 specimens;
Sea of Okhotsk (Iturup, Shikotan and Kunashir) – 6 specimens;
South-western shore of Sakhalin Island – 1 specimen;
South Kuril Islands – 3 specimens;
Bering Sea – 1 specimen;
Bering Sea – 1 specimen; Barents Sea – 1 specimen.
Scientists hypothesized that leatherback turtles began to swim into the seas of the Far East due to the cyclical warming of water and climate. This is confirmed by the catch dynamics of pelagic marine fish and the discovery of other southern species of marine fauna.
