For the first time in 20 years, olive ridley turtles have come to lay their eggs on Mumbai's Versova Beach.

Eyewitnesses of the unique event were passers-by and everyone who ended up on Versova Beach in Mumbai early Thursday morning. Here, for the first time in twenty years, little turtles hatched. Due to deteriorating human-caused environmental conditions, turtles left these places more than two decades ago and chose their nesting sites in other states, where environment not as polluted as in Mumbai. The most "popular" among turtles today is the coast of Orissa, where they regularly appear and have become already calling card region. But in Mubai, on the Versova beach, especially after the last sensational case, when the Okhi cyclone brought tons of garbage to the shores of Maharashtra and Versova was then one of the most affected beaches.

The olive turtle, or ridley turtle, gets its name from the olive color of its shell. The average length of an adult individual can reach 80 centimeters, and weight - up to 50 kilograms. The male and female of this species are outwardly well distinguishable. The former are much larger in size, they have more massive jaws. In addition, the male's tail protrudes from under the shell, while the female does not. The flipper-like limbs of the Ridley are excellently adapted for an aquatic lifestyle.

Ridley leads a calm, measured lifestyle. She spends the morning in search of food, and during the day she calmly drifts on the surface of the water. The olive turtle feeds mainly on algae, crabs, jellyfish, mollusks and fry. various kinds fish. She shows great curiosity for new types of food. It happened that in the stomach of an olive skull, scientists even found plastic bags!

Olive turtles on the beaches of Orissa

Every year the olive turtles return to the beaches where they once were born. As a rule, this happens in the spring. On these beaches, turtles start breeding, during which each female produces several clutches of eggs. Today, the largest nesting place for these turtles is the already mentioned Indian state of Orissa. Since this species is endangered and listed in the Red Book, local zoologists watch this process with awe and love, protecting turtles from their natural enemies and especially from people. Nevertheless, crowds of tourists come to see this bewitching spectacle. Perhaps such a tradition will now appear in Mumbai.

Olive sea turtles are also called ridleys. The species is considered vulnerable due to a number of threats. You can most often meet representatives of the Ridley genus near the coastal part of the subtropical and tropical sea or ocean.

Description

The olive turtle can grow up to 70 cm in length. Her body weight does not exceed 45 kg. The shape of the shell is heart-shaped, the color is gray-olive. Turtles are born black, they brighten over time. They have a triangular head shape with shallow concavities. The anterior part of the carapace is curved upwards. Males differ from females in a more massive jaw, a depressed plastron and a thick tail.

Habitat

Comfortable places for the olive ridley are the shores of the Indian and Pacific Oceans, South Australia, New Zealand, Micronesia, Japan and the northern regions. Saudi Arabia. Less common in caribbean and in Puerto Rico. In water, the animal can dive to a depth of no more than 160 m.

and food

The behavior of olive turtles is characterized by constant calmness. In the morning they are in search of food, and the rest of the day is spent in measured swimming on the surface of the water. They prefer to be in the company of their own kind all the time. From the sharp cooling of the water, they are saved by the fact that they huddle into a large livestock, thereby retaining heat. In moments of imminent danger, they prefer to avoid it in any way. On land, their lives are threatened by wild pigs, opossums and snakes that ruin the masonry.

The olive turtle can be called an omnivore, but more often it prefers animal food. Its usual diet includes various invertebrates (shrimp, crabs, snails and jellyfish). It also feeds on algae. Sometimes swallows inedible objects, including garbage thrown out by people (fragments of plastic bags, polystyrene, etc.). While in captivity, it can eat members of its own species.

reproduction

Every spring or early summer (the onset of the mating season depends on the place of mating), an adult olive turtle, the photo of which is presented below, returns to the beach where it first saw the light, to continue its kind. Moreover, the breeding site throughout life cycle remains unchanged. This phenomenon was called "arribida" (Spanish for "coming"). Turtles determine the place of their birth accurately, despite the fact that they can experience the period of growing up in other territories. According to biologists, olive ridleys use the Earth's magnetic field as a guide.

An animal is considered sexually mature when its body length is at least 60 cm. Mating of the male and female takes place in the water, and the eggs are laid on land. First, a female individual rakes a hole about 35 cm deep with her hind legs. Then the female lays about a hundred eggs, after which she backfills it with sand and tramples it, thereby making the place inconspicuous for natural enemies. This completes the maternal mission of the turtle - she returns to the lands of her permanent residence. The offspring is left to itself or to chance.

Temperature is the main factor influencing the sex of a reptile. In a cold environment, males are formed, and in a warm environment (more than 30 degrees Celsius) - females. The incubation period lasts about 45-50 days. At the end of this period, the hatched turtles get to sea or ocean water. They do this exclusively at night, thereby reducing the risk of collision with predators. A special egg tooth allows turtles to deftly break through the shell.

population

In the water and on land there are many creatures that strive to feast on olive ridleys. The embryos are eaten by coyotes, crows, dogs, vultures, and others. Hatched young turtles are fed by the above predators, as well as frigatebirds and snakes. In the sea and ocean main danger represent sharks. Most turtles do not have time to live to puberty, which is why the number of individuals is rapidly declining.

There are other reasons why the species is listed in the Red Book. The olive turtle is a constant victim of illegal capture. For poachers, both adults and egg embryos are valuable. Further, ridleys end up in the kitchens of trendy restaurants, among whose visitors dishes from turtle meat are in demand.

The number of broods also depends on the environmental factor and natural disasters. Garbage drifting in the world's oceans, a curious turtle loves to swallow, thereby causing irreparable harm to his body. Reptiles often get caught in fishing nets. This threatens animals with rapid death. However Lately fishermen use modern nets in which it is impossible for a large turtle to get entangled.

Many people in India and Mexico, both in voluntary, so on state level they use the incubation method, after which they release the born olive turtles into the long-awaited expanse of water. As for life expectancy, the age of the most dexterous individuals can reach 70 years.

olive sea ​​turtle Ridley - Lepidochelys olivacea- lives in southern waters Atlantic, as well as in the tropical and subtropical regions of the Pacific and Indian Oceans between 40 degrees north and south latitude. In North America, it is found in the waters of the Caribbean Sea and in the Gulf of California. The most famous turtle beach is located in the Bhitar Kanika Reserve in the Bay of Bengal (Orissa, India).

Ridley's olive turtle belongs to large sea turtles weighing 45 kg and with a shell length of up to 55-75 cm, which is not considered for sea turtles large sizes. The soft parts of the body are olive-gray in color. The head is narrow. The tail of the male protrudes from under the shell, while that of the female is under the shell. The thickness of the shell is relatively thin, has a heart-shaped outline, olive color. The paws have two claws. It is primarily a carnivorous turtle, feeding on invertebrates as well as jellyfish, snails, and crabs. It readily tries new foods, and plastic bags and other debris have been found in the stomachs of some turtles. In conditions of detention, they are prone to cannibalism, that is, eating their own kind. Turtles feed in shallow water on soft-bottomed shallows. It feeds on benthos in the absence of other food resources.

Although the exact age at which the turtle begins to produce offspring is not known, this does not occur until it reaches a length of 60 cm. Mating occurs on the beaches in spring and early summer in North America, and turtles do not adhere to monogamy. Sperm is stored in the female to fertilize the eggs throughout the season. Females return to the places where they were born, finding their way by smell. They lay their eggs at night in the first or last quarter of the moon. The clutch contains 300 or more eggs, but on average 107, which the female buries at a depth of 35 cm, after which she returns to the sea. The entire laying process takes the female less than an hour. The female can repeat such clutches monthly. The eggs resemble ping-pong balls and have an incubation period of 45-51 days, with ground temperature determining the sex of the young turtles.

Little is known about social life Ridley tortoises, except that they migrate each year to the beaches to lay their eggs. At other times, the turtle feeds in the morning hours, and during the day it drifts on the surface of the water, exposing its shell to the sun's rays. At such a time, they can gather a lot in one place. This takes place in cool waters. When the turtle gets into warm water shallow, she doesn't need the sun to tan. In the event of a collision with natural enemy(including with a person), the turtle prefers to dive deep to get away from persecution. On land, turtles are threatened by possums, feral pigs, and snakes that hunt for eggs. Adult males, once on land, defend themselves by waving their front paws.
The Ridley tortoise spends almost all its life in coastal waters, not moving further than 15 km from it, preferring to feed on the shallows and lie in the sun. Recorded encounters with turtles in the open ocean.

Since the extraction of turtle eggs became legal in Costa Rica in 1987, local residents have sold 3 million eggs every season. This number included only eggs laid in the first 36 hours, since the next clutches destroyed the previous ones - approximately 27 million eggs.

Along with other sea turtles, the olive Ridley turtle is considered marine predator, as fishermen often find them in their nets. Over the past 30 years, turtle populations have declined significantly as a result of hunting for females that come to the beach to lay their eggs, which serve as a source of meat and skin. The number of turtles is also limited by the space on which they can lay their eggs - worldwide, only five beaches are suitable for their purposes. The governments of some countries are preparing laws to protect or restrict the extraction of turtles, in the United States, the extraction of turtles is also limited.

Atlantic ridley turtle - Lepidochelys kempii lives in the Caribbean Atlantic coasts France, Spain, England, in the southeast of Mexico (Yucatan), in the Gulf of Mexico, Colombia. The length of the shell is 70 cm, weight up to 45 kg. For a long time these turtles were classified as loggerhead hybrids ( caretta) and bisses ( Eretmochelys) or green turtle ( Chelonia), but today it is considered a separate species.

Based on materials from the site http://animaldiversity.ummz.umich.edu/.

  • Class: Reptilia = Reptiles
  • Order: Testudines Fitzinger, 1836 = Turtles
  • Family: Cheloniidae Gray, 1825 = Sea turtles

Genus: Lepidochelys Fitzinger, 1843 = Ridleys, olive turtles

There are two species of sea turtles in the genus, distributed in tropical and subtropical seas, excluding the Mediterranean Sea.

In the IUCN Red List and Appendix I of the Convention on international trade both species are included: the Atlantic ridley L. kempii and the olive turtle L. olivacea.

Ridley's olive sea turtle - Lepidochelys olivacea- lives in the southern waters of the Atlantic, as well as in the tropical and subtropical regions of the Pacific and Indian oceans between 40 degrees north and south latitude. In North America, it is found in the waters of the Caribbean Sea and in the Gulf of California. The most famous turtle beach is located in the Bhitar Kanika Reserve in the Bay of Bengal (Orissa, India).

Ridley's olive turtle belongs to the large sea turtles weighing 45 kg and with a shell length of up to 55-75 cm, which is not considered large for sea turtles. The soft parts of the body are olive-gray in color. The head is narrow. The tail of the male protrudes from under the shell, while that of the female is under the shell. The thickness of the shell is relatively thin, has a heart-shaped outline, olive color. The paws have two claws. It is primarily a carnivorous turtle, feeding on invertebrates as well as jellyfish, snails, and crabs. It readily tries new foods, and plastic bags and other debris have been found in the stomachs of some turtles. In conditions of detention, they are prone to cannibalism, that is, eating their own kind. Turtles feed in shallow water on soft-bottomed shallows. It feeds on benthos in the absence of other food resources.

Although the exact age at which the turtle begins to produce offspring is not known, this does not occur until it reaches a length of 60 cm. Mating occurs on the beaches in spring and early summer in North America, and turtles do not adhere to monogamy. Sperm is stored in the female to fertilize the eggs throughout the season. Females return to the places where they were born, finding their way by smell. They lay their eggs at night in the first or last quarter of the moon. The clutch contains 300 or more eggs, but on average 107, which the female buries at a depth of 35 cm, after which she returns to the sea. The entire laying process takes the female less than an hour. The female can repeat such clutches monthly. The eggs resemble ping-pong balls and have an incubation period of 45-51 days, with ground temperature determining the sex of the young turtles.

Little is known about the social life of the Ridley tortoises, except that they migrate each year to the beaches to lay their eggs. At other times, the turtle feeds in the morning hours, and during the day it drifts on the surface of the water, exposing its shell to the sun's rays. At such a time, they can gather a lot in one place. This takes place in cool waters. When a turtle hits the warm water on a shallow, it doesn't need the sun to tan. In the event of a collision with a natural enemy (including humans), the turtle prefers to dive deep to escape pursuit. On land, turtles are threatened by possums, feral pigs, and snakes that hunt for eggs. Adult males, once on land, defend themselves by waving their front paws.

The Ridley tortoise spends almost all its life in coastal waters, not moving further than 15 km from it, preferring to feed on the shallows and lie in the sun. Recorded encounters with turtles in the open ocean.

Since the extraction of turtle eggs became legal in Costa Rica in 1987, local residents have sold 3 million eggs every season. This number included only eggs laid in the first 36 hours, since the next clutches destroyed the previous ones - approximately 27 million eggs.

Along with other sea turtles, the Ridley's olive turtle is considered a marine predator as fishermen often find them in their nets. Over the past 30 years, turtle populations have declined significantly as a result of hunting for females that come to the beach to lay their eggs, which serve as a source of meat and skin. The number of turtles is also limited by the space on which they can lay their eggs - worldwide, only five beaches are suitable for their purposes. The governments of some countries are preparing laws to protect or restrict the extraction of turtles, in the United States, the extraction of turtles is also limited.

Atlantic ridley tortoise - Lepidochelys kempii lives in the Caribbean Sea, on the Atlantic coasts of France, Spain, England, in the southeast of Mexico (Yucatan), in the Gulf of Mexico, Colombia. The length of the shell is 70 cm, weight up to 45 kg. For a long time, these turtles were classified as loggerhead (Caretta) and hawksbill (Eretmochelys) or green turtle (Chelonia) hybrids, but today it is considered a separate species.

Based on materials from the site http://animaldiversity.ummz.umich.edu/.

The olive turtle, also known as the olive ridley, is a small sea turtle that is now under protection due to the threat of extinction due to extermination by humans and the influence of natural threats. She prefers tropical and subtropical waters of the seas and oceans, mainly the coastal part.

Description of the olive turtle

Appearance

The color of the shell - gray-olive - corresponds to the name of this species of turtles.. The color of newly hatched turtles is black, juveniles are dark gray. The shape of the carapace of turtles of this species resembles the shape of a heart, its front part is curved, and its length can reach 60 or even 70 centimeters. Along the lower edge of the olive turtle shell there are from four to six or more pairs of porous structure scutes on one side and the same number on the other side, about four in front, which is also distinctive feature this type of turtle.

This is interesting! Olive ridleys have flipper-like limbs, which they control perfectly in the water. The head of these turtles resembles the shape of a triangle when viewed from the front, the sides of the head are flattened. They can reach a body length of up to 80 centimeters, and a weight of up to 50 kilograms.

But males and females have differences by which they can be distinguished: males are more massive, unlike females, their jaws are larger, the plastron is concave, the tail is thicker and is visible from under the carapace. Females are inferior in size to males, and their tail is always hidden.

Behavior, lifestyle

The olive ridley, like all turtles, leads a calm measured mode of life, does not differ in constant activity and fussiness. Only in the morning she takes care of finding food for herself, and in the afternoon she calmly drifts on the surface of the water.. These turtles have developed a flocking instinct - straying into a large population, they retain heat so as not to be exposed to hypothermia in sea and ocean waters. They shy away from potential danger and are ready to avoid it at any moment.

Lifespan

On life path many dangers and threats arise for these reptiles, which only the most adapted individuals can overcome. But those dexterous, hardy lucky ones may be given the opportunity to live relatively long life— about 70 years old.

Range, habitats

Ridley can be found both at the edge of the ocean and in its open spaces. But the coastal zones of the tropical latitudes of the Pacific and Indian Ocean, the coast South Africa, New Zealand or Australia from the south, as well as Japan, Micronesia and Saudi Arabia from the north - its usual habitat.

This is interesting! IN pacific ocean this type of turtle can be found starting from the Galapagos Islands and ending with the coastal waters of California.

The Atlantic Ocean is not included in the territory of the olive turtle and is inhabited by its relative, the small Atlantic ridley, with the exception of the coastal waters of Venezuela, Guyana, Suriname, French Guiana and northern Brazil, as well as the Caribbean Sea, where the ridley can be found even near Puerto Rico. She lives in the deep ocean and sea ​​waters where it can descend to a distance of up to 160 m.

Olive turtle nutrition

The olive turtle is omnivorous, but prefers food of animal origin. The usual diet of the olive ridley consists of small representatives of the marine and ocean fauna, which it catches in shallow water (mollusks, fish fry, and others). She does not disdain jellyfish, crabs. But she can readily eat algae or other plant foods, or even try new types of food, up to waste thrown into the water by humans.

Reproduction and offspring

When the turtle reaches a body size of 60 centimeters, we can talk about reaching sexual maturity. The mating season of Ridley starts differently for all representatives of this species, depending on the place of mating. The mating process itself takes place in the expanses of water, but baby turtles are born on land.

For this on the coast North America, India, Australia, representatives of this species of turtles arrive in order to lay eggs - they themselves were born here at one time and now strive to give life to their own offspring. It is surprising, however, that olive tortoises come to breed in the same place during their entire life cycle, and all together on the same day.

This feature is called “arribida”, this term is translated from Spanish as “coming”. It is also noteworthy that the turtle unmistakably determines the beach - the place of its birth - even if it has never been here since its birth.

This is interesting! There is an assumption that they are guided by the Earth's magnetic field; by another guess

The female olive ridley rakes the sand with her hind legs to a depth of approximately 35 centimeters and lays about 100 eggs there, then makes this place inconspicuous for predators, throwing sand and trampling it down. After that, considering her mission to reproduce offspring completed, she goes to the ocean, on her way back to her permanent habitat. The offspring at the same time becomes left to itself and the will of fate.

This is interesting! A fact that affects the fate of small turtles is the ambient temperature, the level of which will determine the sex of the future reptile: most male cubs are born in cold sand, and female ones in warm (more than 30 C 0).

In the future, the cubs of the olive turtle themselves will have to, after the expiration of the incubation period, somewhere in 45-51 days, having hatched from the eggs and guided only by the instinct inherent in them by nature, get to the saving waters of the ocean - natural environment the habitat of these wonderful animals. Turtles do this under the cover of night, fearing predators.

They pierce the shell with a special egg tooth, and then make their way through the sand to the outside, rushing to the water. Both on land and in the ocean, many predators lie in wait for them, so olive turtles survive in very small numbers until adulthood, which prevents the rapid restoration of the population of this species.