Galapagos tortoise

Description

They are the largest tortoises that exist, along with tortoises in the Seychelles group in the Indian Ocean. The largest specimens can measure up to 1.8 metres long and weigh some 400 kg. Their longevity is also incredible and the oldest animal known of today, called ‘Solitary George’, is believed to be over 150 years old.
As the environment, landscape and climate vary greatly from one island to another, and even within a single island, the morphology, size and weight of the different tortoise populations also change, to the point that up to fifteen subspecies are recognised, of which only eleven survive today. Some authors separate even these subspecies into different species, although this is not the most commonly used criterion of specialists.
The scientific name of this impressive tortoise is Geochelone nigra, although it is also called Geochelone elephantopus and Chelonoides nigra.
Their diets are principally herbivorous, as they feed on grasses, leaves, marram grasses and fruits of different plant species, including cacti, although they can also eat carrion and other organic remains. Oviparous, the female lays from 4 to 10 eggs, which are placed in holes dug into the sand. During copulation, males bray loudly and this sound is audible at considerable distances.
During the rainy season, they spend a good part of their time in the mud or semi-submerged for heat regulation and protection against parasites. They form a very loose social structure based on a hierarchy defined basically by size. They often interact very aggressively, hitting their shells against each other and biting the extremities, both in fights between males and when courting.
The impressive abundance of tortoises that the first visitors to the islands found is now sadly a thing of the past, due to overhunting, particularly during the 19th century, by sailors who took them aboard ships for fresh meat during long sea crossings, using the animal to make up for water and food shortages.
Moreover, the introduction of exotic species like rats, dogs, cats and goats to the fragile ecosystem of the Galapagos Islands has also contributed to the great decrease in their populations.
 The Barcelona Zoo participates in the European Studbook (ESB) for this species in captivity.