Out of the 54 endemic bird species found on the islands, 22 are land birds. Of those 22 endemic land birds, 13 are the famous Darwin finches.
*endemic at the subspecies level
- Galápagos short-eared owl*
- Galápagos barn owl*
- Galápagos flycatcher
- Vermilion flycatcher*
- Galápagos mockingbird
- Floreana mockingbird
- Española mockingbird
- San Cristóbal mockingbird
Between two and three million years ago a single species of finch colonized the Galápagos islands. The 13 species that exist today are classified largely by the habitat they live in (on the ground or in the trees) and the shape of their beaks, which are specialized based their food (fruits, seeds, insects, or cactus).
Rice rats hold the world record for ocean distance traveled by a terrestrial mammal after probably floating to the islands on rafts of vegetation from mainland South America. Only two of the seven endemic species of rice rats now exist on the islands living only on the non-inhabited islands, Fernandina and Sante Fé. The other five species were killed off by predation and disease after humans introduced black rats, cats, and dogs.
Bats are historically the most successful mammalian colonizers. There are two bat species on the islands, one of which is endemic. Galápagos red bats are most closely related to the South American red bat with a more restricted range that the more widespread hoary bat. The Hoary bat originated from North America and is not endemic to the islands.
There are over 2200 species of invertebrates on the islands, and new species are being discovered. Of these species 51.7% are considered endemic. Land snails alone account for 60 different, endemic species. Invertebrates (slime molds, worms, beetles, grasshoppers, bees, butterflies, winged insects, etc.) play a vital role in the ecosystem including pollination, decomposition, and are prey for many other species. Introduced species including two species of fire ants, two species of wasps, and a parasitic fly have devastated native flora and fauna.
Due to their long life span and ability to go up to a year without water the Galápagos giant tortoises are well adapted to the environment of the volcanic islands, but these adaptations, large size (up to 600lbs), and their slow movement made them easy targets for explorers, sealers, and whalers. As a result of intense harvesting for use as food and oil throughout the 19th century only 9 of the 14 identified species remain. Today the giant tortoises can be found on the ten largest islands but continue to face pressure from introduced species, especially goats and rats. The Galápagos National Park and conservationists are hopeful that invasive species removal and prevention programs will help protect giant tortoises.
There are three species of land iguanas on the Galápagos, two yellow iguanas, and the pink iguana. The yellow iguana Conolophus subcristatis is native to six of the islands while the other yellow iguana, C. pallidus, is limited to only Santa Fe. The pink iguana was found in 1984 but not classified as its own species until 2009, and is only found at Volcán Wolf on Isabela, where their may be about 500 individuals. The land iguanas on Santa Cruz Island were decimated by wild dogs brought to the island by people. The Galápagos National Park responded and implemented a captive breeding and rearing program with help from the Charles Darwin Station. The population is again considered stable and the program ended in 2008. The famous marine iguanas, endemic the Galápagos Islands, are considered a marine species.
While the giant tortoises and iguanas are the endemic reptiles most people know from the Galápagos Islands. Other endemic reptiles include: five species of snakes; nine species of lava lizards; seven species of geckos, six are endemic; and one tree frog that was introduced.
Darwin Foundation Species Checklist: http://www.darwinfoundation.org/datazone/checklists/
Thornton, Ian. Darwin’s Islands: A Natural History of the Galápagos. N.p.: American Museum of Natural History, 1971. Print.