Aldabra Giant Tortoise ("Seychelles giant tortoise")

Aldabrachelys gigantea gigantea
 The Aldabra giant tortoise (Aldabrachelys gigantea, Syn .: including Geochelone gigantea, Dipsochelys elephantina and Dipsochelys dussumieri) is the only recent representative in the genus of the Seychelles giant tortoises (Aldabrachelys) from the family of real tortoises (Testudinidae).

The most striking feature of the Aldabra giant tortoise is its relatively small head, which only slightly protrudes from the diameter of the neck. Other distinguishing features from the Galápagos giant tortoise are large scales of the head, the presence of a neck shield, vertically slit nostrils and the ability to drink through the nose.

Like the smaller tortoise species, giant tortoises have a pronounced sexual dimorphism. Males have a longer tail, are larger, and have a concave (inwardly curved) belly armor and a flatter back armor than females. Usually they also have longer toenails on their hind legs. These secondary characteristics only appear in the run-up to sexual maturity from a shell length of about 60 cm. Sexual maturity is reached between 15 and 30 years of age.

The largest carapace lengths are given for males with 100–122 cm and for females with 87 cm, including maximum weights of 250 kg for males and 167 kg for females. The average weights of the populations, depending on the age structure and food availability, are, however, significantly lower at 20–50 kg.

Some captive individuals with an unusually shaped, saddle-shaped shell were called "Arnold's giant tortoise" for some time. Based on genetic investigations, Gerlach (1996) initially believed that they were remnants of an extinct species and assigned them their own species status. However, this was refuted in 2003 by renewed investigations by Austin and Palkovacs. This species is not included in the current listing for CITES.

98% of the natural populations live on the main island of the Aldabra Atoll, Grande Terre, in the Indian Ocean, preferring its coastal areas and open grass and scrubland with low vegetation. The temperatures fluctuate between mean minimum values ​​of 22 ° C and mean maximum values ​​of 31 ° C. In these semi-arid areas, through the thousands of years of browsing by turtles, a vegetation of genetically dwarfed grasses and sedges has developed, the so-called tortoise turf, which is the main source of food for the animals. It consists of grasses, herbs and flowers. In addition, fruits, occasionally carrion and droppings are eaten.

Source: Wikipedia

Aldabra giant tortoises can easily live to be over 100 years old. The male Adwaita, born in the first half of the 18th century, presumably lived a life span of 256 years in captivity. The oldest living specimens are Jonathan on St. Helena (* approx. 1834) and Esmeralda on Bird Island, possibly over 200 years old.

The main mating season is in the rainy season from October to April, while the egg-laying time is in the cooler months of June to September. One to two, occasionally up to three clutches with 5 to 25 eggs per clutch are laid. The eggs are the size of a tennis ball and weigh between 40 g and 75 g. The nest holes are preferably created in areas with five hours of sun exposure. Temperatures between 27 ° C and 31 ° C are around 25 cm deep. The young animals hatch with a size of 6 to 7 cm shell length in a sex ratio of approx. 1: 1. They can stay in the nest cavity for up to a month until they usually dig to the surface together after a rain.

The total free-living population is around 100,000 animals (Bourn 1999), and around 5,000 specimens are kept in zoos and in private hands (Swingland 1985). Thus, it is the only giant tortoise whose survival is considered to be reasonably assured according to the current status. However, due to the small area of distribution, natural disasters, epidemics, introduced species and human impact could have far-reaching effects. The Aldabra giant tortoise is listed in Appendix B of the European Species Protection Ordinance. It is therefore subject to official reporting, but may be bought or sold without a marketing permit.

In 1985 the Seychelles Post issued a separate issue for the Outer Islands with a 10 rupee pad with a picture of two giant tortoises.

In 1998 the Post of the Kingdom of Cambodia issued a postage stamp depicting a giant Aldabra tortoise with a face value of 1,500 riels.

In 2008 the Indian Post honored Adwaita, who died in Calcutta Zoo after more than 256 years of life, with two hexagonal stamps with a face value of 5 rupees and 15 rupees.

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