Galapagos Tortoise

These giants are the largest tortoises in the world. The biggest one ever recorded, measured across its shell, was five feet (1.5 meters) long and weighed about 550 pounds (249 kilograms). These tortoises can live to be 100 years old or older. The oldest known Galápagos tortoise lived to be 152. These slow-moving reptiles graze on grass, leaves, fruits, vines, cactuses, and other vegetation.

Giant Galápagos tortoises are endangered. They live in the wild only in parts of the Galápagos Islands, a group of islands in the Pacific Ocean about 600 miles (966 kilometers) off the coast of Ecuador in South America. Approximately 3,000 to 5,000 of these animals still survive there. Up until the 19th century, they were often hunted by sailors who needed fresh meat to eat.

Pirates, whale hunters, and merchant sailors made stops in the Galápagos to restock their supplies of food and water. They quickly added Galápagos tortoises to their diet because these giants can survive for a year without eating or drinking. This meant the sailors could keep the reptiles onboard on long journeys without having to care for them.

More than 100,000 tortoises are thought to have been killed during that time. The ones that survive today are now protected by laws. The biggest threat to these tortoises now is animals who are not native to the Galápagos Islands.

 Dogs, cats, rats, and pigs eat tortoise eggs as well as young tortoises. Goats and cattle eat the same vegetation that the tortoises eat, causing shortages of food. Galápagos tortoises are quiet, peaceful animals that sleep nearly 16 hours per day. 

Like all reptiles, they are cold-blooded, which means their body temperature stays about the same as the environment around them. They need the warmth of the sun to keep from freezing, so they are often seen out in the open, basking in the sunlight.

FAST FACTS
The scientific name of the giant Galápagos tortoise is Geochelone elephantophus.

An adult giant Galápagos tortoise is generally about four feet (1.2 meters) long and weighs some 475 pounds (215 kilograms).

There used to be 15 subspecies of Galápagos tortoises; now there are only 11. The different subspecies live in different habitats and have physical characteristics and behaviors shaped by where they live.

The populations of Galápagos tortoises that live on the hotter and drier islands of the Galápagos have developed shells that are saddle-shaped with a high notch above the neck. This allows them to stretch their necks higher to reach vegetation that grows above the ground.

The populations of tortoises that live on the islands that are generally cooler and wetter have dome-shaped shells. They feed on vegetation that grows at ground level, so they don't need to reach high for food the way the saddle-backed tortoises do.

The Charles Darwin Research Station in the Galápagos raises captive Galápagos tortoises. This conservation organization reintroduces many tortoises back into the wild once they've grown big enough that predators don't pose a danger.

In 1959, the government of Ecuador designated all unsettled areas in the Galápagos as a national park. Since then, all the wildlife of the islands, including the Galápagos tortoises, have been protected by law, and people could no longer hunt or take the tortoises off the islands.

The only native natural predator of the Galápagos tortoise is the Galápagos hawk. The hawk preys on eggs and newly hatched tortoises. The main threats to adult tortoises are habitat destruction and illegal hunting.

The top shell of a tortoise is called the carapace. The shell that covers a tortoise's belly is called the plastron.

The Galápagos Islands, discovered by Spanish sailors in 1535, were named after the giant tortoises discovered there. Galápago means tortoise in Spanish.

Tortoises lay eggs. Females lay their eggs in nest holes, which they cover and leave. Babies hatch in four to eight months. They are on their own from the beginning.