Isla Bertolomé, Galapagos Islands, Ecuador Photograph by John Lamoreux   Galápagos Islands, off the coast of Ecuador Deserts and Xeric Shrublands   3,100 square miles (8,000 square kilometers) -- about half the size of Hawaii Critical/Endangered

· Islands of Iguanas
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Islands of Iguanas

Near the south shore of Fernandina Island in the Galápagos, large groups of marine iguanas can be seen sunning themselves on the rocks among the tube-like cactuses. They soon plunge into the water to feed on algae that clings to the rocks along the shore and under water. In the higher elevations, you might see land iguanas, which are similar yet distinct from their marine counterparts. These iguanas, which can be seen munching on terrestrial plants, are just a few of the many animals that inhabit these isolated islands.

Special Features

The Galápagos consist of 13 large islands and 115 smaller ones, all of volcanic origin. This unique ecoregion lies 620 miles (1,000 km) west of Ecuador, where it straddles the equator. People are permitted to live on the four main islands: Isabela (the largest), Fernandina, Santiago, and Santa Cruz. This varied ecoregion is influenced by many different elevations, amounts of rainfall, and wind patterns. Three basic plant communities exist--a dry-arid-desert scrub, humid woodlands, and a transition zone between the two. These islands are most commonly known for their important role in the study of evolution. The islands’ isolation has created a natural laboratory in which animals have evolved without influence from mainland species. Charles Darwin studied evolution here, noting that the islands’ finches and mockingbirds are quite unlike their mainland relatives.

	The warm waters of the Galápagos are home to a kind of bird that most people associate with the icy world of Antarctica. The Galápagos penguin is found farther north than any other species of penguin on Earth.

Wild Side

The animals of this ecoregion often depend on each other. For example, when a ground finch is ready for a meal it will hop up and down in front of a land iguana or giant tortoise. The iguana or tortoise then allows the finch to pick ticks and other parasites off its body. Thus, the finch gets a meal and the reptile is freed of some pests. A different kind of relationship exists between the sharp-billed ground finch and the blue-footed booby. The sharp-billed ground finch pecks at a booby until it bleeds, then drinks its blood. No wonder the finch is also known as the "vampire finch." Another finch--the woodpecker finch--has evolved the ability to use a prickly pear cactus needle held in its beak to pry insect larvae from dead tree branches.

Cause for Concern

Overgrazing by livestock, predation by exotic species, human-induced fires, poaching, and over-harvesting of marine resources are serious threats to this ecoregion. Recently, an oil spill and difficulties enforcing conservation regulations have been issues of concern as well. Introduced species continue to pose a problem. In the 1800s, pirates and whalers introduced alien species such as goats to these islands. Today, the goats pose severe threats and currently number near 125,000 on Isabela Island.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.