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The Native Habitat for the Dome-Shaped Tortoise

Galapagos giant tortoises, known by the Latin name Geochelone elephantopus, or Geochelone nigra, are found only on the Galapagos Islands. Before being depleted by 19th century whalers and pirates, the tortoises lived on most of the islands. The terrestrial, or land-dwelling, turtles have two general shell morphologies. They are known as the dome-shaped and saddleback types. An intermediate form also exists. The dome-shaped tortoises are the largest type, with males reaching 700 pounds and females up to 400 pounds.

Geographical Distribution
- The dome-shaped giant Galapagos tortoise is endemic, or native to the Galapagos Islands. The turtles' habitat is restricted to about a half dozen of the 50 islands situated directly on the equator. Officially known as the Archipielago de Colon, the archipelago of volcanic islands are located in the eastern Pacific Ocean, approximately 620 miles west of the Ecuadorian coast. The islands occupy an area covering 2,796 square miles and are a province of Ecuador.
Feeding Habits
- The dome-shaped varieties of the Galapagos giant tortoise evolved a tall profile with a domed carapace, or shell, in response to available food sources present in their natural habitat. The front bony plates of the shell angle slightly downward, preventing the tortoises from stretching their necks upward to graze on tall vegetation. They feed on fallen manzanello tree fruits, cactus pads, vines and grasses. A large population of dome-shaped tortoises live on the vegetated slopes of Alcedo Volcano on Isabela Island.
Elevation
- The dome-shaped tortoises live on parts of the larger islands with plentiful vegetation to support their large body mass. This is generally the humid highlands above 2,625 feet, though they may migrate to lower elevations below 2,000 during the wet season. The tortoises move from the drier coastal regions to the higher, wetter elevations following the changing rainfall patterns of the island. Males and females meet up in the highlands to breed, with the females moving to the lower, drier areas to nest.
Micro-Environments
- Dome-shaped Galapagos tortoises spend the day feeding in the highlands, then follow established trails and well-worn paths through the brush to the lowlands where water accumulates in pools. They prefer to rest in mud-wallows or half submerged in small ponds and water holes. Sometimes they relax under heavy brush. The tortoises can be found sharing the habitat of Darwin's finches. They stretch out their necks to allow the birds to eat insects and seeds stuck in their wrinkly skin. They sometimes are found floating in the islands' coastal waters.

Animals & Science