Olive ridged turtle

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Olive ridged turtle
Olive ridged turtle near Mahabalipuram in the Indian state of Tamil Nadu

Olive ridged turtle near Mahabalipuram in the Indian state of Tamil Nadu

Systematics
Order : Turtles (Testudinata)
Subordination : Halsberger tortoises (Cryptodira)
Family : Sea turtles (Cheloniidae)
Subfamily : Carettinae
Genre : Ridged tortoises ( Lepidochelys )
Type : Olive ridged turtle
Scientific name
Lepidochelys olivacea
( Eschscholtz , 1829)

The olive ridged turtle ( Lepidochelys olivacea ) or Pacific ridged turtle (Pacific ridged turtle) is a species from the family of sea ​​turtles , which belongs to the genus of ridged turtles . The hybrid turtles got their names because they used to be considered a hybrid between the green turtle and the loggerhead turtle .

Appearance

With a body length of around 70 cm and a maximum weight of 50 kg, the olive hybrid turtle is one of the smallest species among sea ​​turtles . It bears its name because of the olive-green color with the greenish drawing elements of the heart-shaped shell. The color of the belly armor is yellowish green. Young animals, on the other hand, are gray-black on the upper side and cream-colored on the underside.

The sexes can be differentiated by the fact that males have a concave plastron and a longer tail. They also have a longer, curved claw on their front feet. This helps the male to cling to the female's carapace during mating.

The olive ridged turtle is similar to the Atlantic ridged turtle in appearance and behavior, but that species has a gray-green shell and the shell is shorter and flatter.

Distribution area and diet

Distribution map of the species: important nesting sites in red, less important ones in yellow.

The olive ridged turtle lives primarily in the Indian and Pacific Oceans and is found on the Asian and American coasts of these oceans. It prefers to stay in shallow coastal waters and prefers those with a high proportion of suspended matter and a low salinity .

The olive ridged turtle feeds on sea ​​snakes , crabs , cephalopods , jellyfish , sea ​​urchins and other marine animals. The assumption that the animals also feed on plants is not supported by documented observations. They can dive at least 150 meters in search of food.

Reproduction

Olive ridged turtle laying eggs
Every year, thousands of females arrive to lay their eggs in the protected area of Playa de Escobilla on the Mexican Pacific coast
Olive ridged turtle embryo

A total of 47 areas are known where olive ridged turtles lay eggs.

The two species of ridged turtle are the only species that have seen massive landings on breeding beaches. Occasionally several thousand females can be seen on a short stretch of beach. The largest Indian nesting colony, for example, is located at Gatirmatha on the Krishna-Godavari basin (between the Godavari and Krishna rivers ). Long-term studies carried out from 1976 to 1993 showed that 130,000 to 610,000 female olive ridged turtles lay their eggs here every year. The time of day is also unusual because, unlike other sea turtles, they prefer the bright day to land, especially on very windy days. However, the eggs are laid at night.

The clutch size is between 80 and 160 eggs. The incubation time of the eggs is 45 to 60 days. The hatchlings are 4 centimeters tall and weigh 18 to 20 grams.

Endangerment and existence

Olive ridged tortoise, presumably killed by a ship's propeller

Because of their meat and eggs, the olive ridged turtles were hunted intensively like all other sea turtles and are now under international protection under the Washington Convention on Endangered Species . While the population in the Atlantic continues to decline, the number of animals in the peripheral areas of the Pacific appears to be increasing again. However, animals of the species are the most common bycatch in longline fisheries off the coast of Costa Rica.

supporting documents

literature

  • Indraneil Das: The turtles of the Indian subcontinent. Edition Chimaira, Frankfurt am Main 2001, ISBN 3-930612-35-6 .

Individual evidence

  1. ↑ Lepidochelys olivacea . In: Klaus Kabisch: Dictionary of Herpetology. Gustav Fischer Verlag , Jena 1990, p. 267.
  2. ↑ a b Das, p. 51
  3. ↑ a b Das, p. 52
  4. ↑ Das, p. 53
  5. ↑ eurekalert.org  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. from October 2, 2013: Longline fishery in Costa Rica kills thousands of sea turtles and sharks.@1@ 2Template: Dead Link / www.eurekalert.org  

Web links

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