The GALAPAGOS TORTOISE is the largest living species of tortoise and the 13th heaviest living reptile, reaching weights of over 400kg and lengths of over 1.8 mts, with life spans, in the wild, over 100yrs. A captive individual lived at least 170 yrs.
It is native to 7 of the GALAPAGOS ISLANDS, a volcanic archipelago, about 1000 km west of the Ecuadorian mainland. Spanish explorers, who discovered the islands in the 16th century, named them after the Spanish GALAPAGO, meaning TORTOISE. The number of tortoises declined from over 250,000, in the 16th century, to a low of around3000 in the 1970s. This decline was caused by exploitation of the species for meat, oil, habitat clearance, agriculture and introduction of non-native animals, to the island, such as rats, goats and pigs. Ten sub-species of the original 15 survive in the wild; and an eleventh sub-species had only a single known living individual, kept in captivity and nicknamed LONESOME GEORGE, until his death in June 2012. The specie, as a whole, is classified as VULNERABLE by the International Union for Conservation of Nature (IUCN).
Tortoises are ECTOTHERMIC (cold-blooded), and therefore bask for 1-2hrs, before dawn to absorb the sun’s heat through their dark shells, before actually foraging for 8-9hrs a day. They have been observed to walk at a speed of 0.3km per hour. They are herbivores. They consume cacti, grasses, leaves, lichens and berries. A tortoise eats an average of 32-36 kilos per day, with a digestive efficiency roughly equal to that of hindgut fermenting herbivorous mammals such as horses and rhinos. They acquire most of their moisture from the dew and sap in vegetation and can, therefore, survive long periods without water. They can endure 18mths, when deprived of all fat and water, surviving by breaking down their body-fat to produce water as a by-product. When thirsty, they may drink large quantities of water very quickly, storing it in their bladders and the “root of the neck” (the pericardium) both of which serve to make them useful water sources on ships.