Aldabrachelys gigantea hololissa
Giant tortoises are among the longest-lived animals on the planet. Some individual Aldabra giant tortoises are thought to be over 200 years of age, but this is difficult to verify because they tend to outlive their human observers. Adwaita was reputedly one of four brought by British seamen from the Seychelles Islands as gifts to Robert Clive of the British East India Company in the 18th century, and came to Calcutta Zoo in 1875. At his death in March 2006 at the Kolkata (formerly Calcutta) Zoo in India, Adwaita is reputed to have reached the longest ever measured life span of 255 years (birth year 1750). Today, Jonathan, a -year-old, Saint Helena-dwelling Seychelles giant tortoise, is thought to be the oldest living terrestrial animal on Earth since the 2006 death of Harriet; a 176 year old Galapagos giant tortoise who lived at Australia Zoo. Coming in second to Jonathan is Esmeralda, at years old. Esmeralda is an Aldabra giant tortoise that lives in the Galapagos Islands.
Galápagos Islands
Non-native goats, pigs, dogs, rats, cats, mice, sheep, horses, donkeys, cows, poultry, ants, cockroaches, and some parasites inhabit the islands today. Dogs and cats attack the tame birds and destroy the nests of birds, land tortoises, and marine turtles. They sometimes kill small Galápagos tortoises and iguanas. Pigs are even more harmful, covering larger areas and destroying the nests of tortoises, turtles and iguanas, as well as eating the animals' native food. Pigs also knock down vegetation in their search for roots and insects. This problem abounds in Cerro Azul volcano and Isabela, and in Santiago, pigs may be the cause of the disappearance of the land iguanas that were so abundant when Darwin visited. The black rat ("Rattus rattus") attacks small Galápagos tortoises when they leave the nest, so in Pinzón they stopped the reproduction for a period of more than 50 years; only adults were found on that island. Also, where the black rat is found, the endemic rat has disappeared. Cattle and donkeys eat all the available vegetation and compete with native species for the scarce water. In 1959, fishermen introduced one male and two female goats to Pinta island; by 1973, the National Park service estimated the population of goats to be over 30,000 individuals. Goats were also introduced to Marchena in 1967 and to Rabida in 1971. A goat eradication program, however, cleared the goats from Pinta and Santiago and most of the goat population from Isabela.
In fact, by 2006 all feral pigs, donkeys and non-sterile goats had been eliminated from Santiago and Isabela, the largest islands with the worst problems due to non-native mammals.