The Galapagos Island Tortoises represent the natural biodiversity of this charming Archipelago.
Galapagos tortoises (Geochelone species) are among the largest on Earth. They can reach weights of over 250 Kg and its shells can measure up to 60 inches.
These land-based turtles are slow moving and known for their long life span of more than 150 years, sometimes even more.
There are 11 sub-species of Galapagos giant tortoises (There were 15 sub-species before). In Epanola and Pinta Islands you can find the smallest tortoises with saddle-shaped backs.
The largest tortoises can be found in the surroundings of Alcedo Volcano on Isabela Island. These tortoises have dome backs.
In this isolated habitat these giant tortoises fill the niche occupied by larger vegetarian mammals in continental regions.
Find Cheap Galapagos Islands Flights here
The giant tortoise was one of the most devastated of all species in the Galapagos Islands. Humans first exploited giant tortoises as a food source. In later years, they were harvested for oil.
Some introduced species like rats, pigs and dogs prey on eggs and young tortoises, others species like goats damage or destroy tortoise habitat.
Fortunately with the establishment of the Galapagos National Park and the CDF in 1959, a systematic review of the status of the tortoise populations began. Only 11 of the 15 original populations remained and most of these were endangered.
The breeding and rearing program for giant tortoises began in response to the conditions of the tortoise population on Pinzon Island, where fewer than 200 old adults were found.
With the eradication of introduced mammals, many of the giant tortoise populations are nearing the point when the breeding and rearing center will no longer be required.
Monitoring their populations and restoring their habitat will now be part of larger Island restoration programs.
Tortoises are vegetarian and eat a wide variety of plants, including Opuntia cacti.
They eat grass and cactus fruit, flowers and stems.
Soon after the rainy season the tortoises descend the mountain slopes to feed on the grass covered flats.
After that grass withers during the dry season they climb the mountain to feed on grasses of the moist meadows.
The different carapaces have probably evolved as adaptations to the different environments on each Island.
Saddle-back types are raised at the front to allow the tortoises' long necks to reach for higher vegetation on drier Islands.
Dome-shaped tortoises do not need to reach for food on moist Islands where lower vegetation is available; however the shape of their shell helps them push through dense growth.
In highland areas, tortoises can be seen wallowing in shallow pools formed by rain or dew dripping from leaves.
Galapagos Island tortoises stand and stretch their necks to give birds access to remove parasites.
When frightened, tortoises retract their heads and legs into the protective shell.
It is said that the Galapagos Island tortoises played an important role in Darwin's Theory of Evolution.
When Charles Darwin visited the Galapagos Islands, he was told by the vice governor of the Archipelago that he could identify what Island the tortoise was from simply by looking at its shape and characteristics.
See a Gallery of Stunning Galapagos Island Pictures
The last remaining male tortoise of Pinta Island known as Solitary George was brought back to the Charles Darwin Research Station, where he is housed in a corral with two females from Wolf Volcano, on Isabela Island. But all the efforts has failed to breed successfully with these females.
Working with communities and establishing protected areas is crucial for the restoration and repatriation of young tortoises close to towns, such as Puerto Villamil on Isabela.
By working together with the Island's inhabitants, the Charles Darwin Research Station is optimistic that the giant Galapagos Island tortoises will continue to be part of the unique Galapagos wildlife.
Ecuador & Galapagos (Insight Guides)
Birds, Mammals, and Reptiles of the Galapagos Islands
Galapagos: The Islands That Changed the World
Moon Spotlight Galapagos Islands
Galapagos: Islands Born of Fire