Scientific Name: Geochelone gigantea
The Aldabra tortoise may be the longest-lived animal on Earth.
The Aldabra is the second largest species of tortoise, being only slightly smaller than the tortoise found on the Galapagos Islands, and comprises the world’s largest population of giant tortoises.
STATUS: Thanks to renowned naturalist Charles Darwin, who successfully petitioned for the protection of these shy, slow-moving creatures, the Aldabra tortoise still survives in its Indian Ocean home. However, the species is listed as Vulnerable by the International Union for Conservation of Nature (IUCN) because its small home islands are at risk of natural disasters and human development.
HABITAT: The Aldabra tortoises’ home territory is on the Aldabra Atoll (a group of coral islands surrounding a lagoon) in the Seychelles Islands of the Indian Ocean. There are several different habitats for the tortoises on the Atoll, including mangrove swamps, scrub and coastal dunes. The largest numbers of tortoises, however, are found in the islands’ grasslands. The animals hide from the hot tropical sun in freshwater or saline pools and mudholes and take shelter under trees or bushes. The Aldabra tortoises used to share their islands with other gigantic tortoises, but by the early 1800s the other species were wiped out by visiting sailors and by introduced animals such as cats, pigs and rats that ate the tortoises or competed with them for food.
DIET: The finely-serrated jaws of the tortoise are used to browse and graze on grasses, small herbs and sedges. Although primarily herbivorous, the animals also eat dead land crabs and even other tortoises. Because water is scarce on the Aldabra Atoll, except during the rainy season, the tortoises obtain most of their water from their food. Since the tortoise is able to stretch its long neck quite far, it is able to reach food about a meter above the ground.
PHYSICAL CHARACTERISTICS: In case of danger, the tortoise is able to retract its snake-like head and legs into its thick, brownish-gray or black shell called a carapace. Adult males have an average carapace length of four feet while adult females average three feet. Mature males can weigh 550 pounds or even more (one in captivity weighs over 800 pounds) and females average 350 pounds. Male Aldabra tortoises have larger and longer tails than the females. The animals’ hind legs are cylindrical and columnar and resemble an elephant’s legs. Their heads and legs are covered in scales.
In order to get food, tortoises have been known to knock over small trees and shrubs. This creates pathways and clearings for other animals. Male tortoises also show their strength during courtship when the animal will hit his shell against the female about a dozen times and then make a deep trumpeting call when mating.