Between the Species of Galapagos that have disappeared There are 12 vertebrates and 3 plants. Among these species are the giant tortoise or the marine iguana.
The cause of the extinction of these species is due in large part to activities such as tourism, the introduction of other species into the ecosystem of the islands and climate changes .
Chelonoidis abingdonii, Galapagos giant tortoise extinct in 2012.
According to the Directorate of the Galapagos National Park or DPNG, the islands currently have lost 5% of the species that originally inhabited them.
This situation is alarming, since all species of reptiles, almost 80% of mammals, approximately 50% of insects and birds, and more than 40% of the plants are endemic to the islands (Quasar, 2017).
The species that inhabit the Galapagos Islands arrived there by a series of coincidences. Giant tortoise eggs are believed to have reached the island in logs or fragments of land. It is also said that most plants and animal species were driven to the island by wind and sea currents.
The most important species that has disappeared from the Galapagos Islands is the giant tortoise of Galapagos. A reptile that could be found only in this part of the world. The last living specimen was named George and died in 2012 on Santa Cruz Island (BLAKESLEE, 2015).
Missing Species of the Galapagos Islands
The ecosystem of the Galapagos Islands has been declared a World Heritage Site. In its archipelago converge four marine currents: Humboldt, Sur-Equatoriales, Panama and Cromwell. Each one of these currents differs in temperature and quantity of nutrients, providing unique conditions of habitability for the species that live in the islands.
Any affectation of these environmental conditions can lead to the extinction of the endemic species of the islands. Among the species that have become extinct in the Galapagos Islands, according to the DPNG can be found the following:
Vertebrates
In the Galapagos Islands there are 109 endemic and native species of vertebrate animals, of which 13 are believed to have been extinct. Seven of these species have been recorded in life, however, the remaining six have been recorded only as fossils. Some of them are:
1- Galapagos Giant Tortoise
Originally in the Galapagos, there were at least eight species of giant tortoises. Three of these species are extinct today, including the giant tortoise of Isla Pinta (Eaton, 2015).
The last specimen of this species was named George, and was discovered wandering only in 1972, so it was placed in custody.
His death was recorded in 2012, and it is believed that the extinction of his species was caused by the change of its ecosystem during the last 200 years, during which the population of this species went from having 250,000 copies during the sixteenth century To have only 3,000 copies in 1970 (Islagalapagos, 2017).
2- Marine iguana
The Galapagos marine iguana is the only reptile in the world that has the ability to live and seek food underwater. Phenomena such as El Niño, contamination And the introduction of predators within the islands has caused some species of marine iguanas to disappear and others to be at risk of extinction (IUCN, 2008).
3- Green turtle
The Galapagos green turtle feeds on algae and marine plants, thus helping the sea floor to stay healthy and more productive. This species is at high risk of extinction and few data have been found on its presence in the islands during the last years.
The cause of this situation is the human consumption of the eggs deposited by the turtles in the islands. The green turtle must sail kilometers before laying eggs, defending themselves against predators that may also endanger their existence.
4- Vermilion Robin
This species is the first bird registered as extinct in the Galapagos Islands. Since 1987 no specimens of this species have been sighted, which is why in 2016 it was officially declared extinct on the island of San Cristóbal (GARZÓN, 2016).
Darwin mouse
In the year 2000 the rat of Darwin's rice field in the Galapagos Islands was declared extinct.
Plants
In the Galapagos islands, 180 species of endemic plants were recorded some years ago. Today, nine of these species do not present record data and it is estimated that three have disappeared altogether. This is due to the arrival of tourists in a constant way to the island and to the climatic changes that affect the ecosystem of the islands.
Other species at risk
Historically, it is estimated that there are 45 species that are at risk of disappearing or have disappeared from the Galapagos Islands during the last centuries. This situation represents a high risk for the islands, since these are a space with little biodiversity and they are located to a great distance of the nearest island.
7% of vertebrate species in the Galapagos are in Danger of extinction . This includes three species of reptiles (two turtles and one snake), and four birds (Mangrove Finch, Galapagos Petrel, Floreana Thrush and Galapagos Albatross).
Apart from these species, there are others at lower risk but which must also be protected because they are in a state of vulnerability. These species include 17 types of reptiles, 9 types of birds, and 5 types of mammals.
Within invertebrate species, you can find the Galapagos land snail, along with different types of moths and butterflies.
Thus, of the 103 invertebrate species that inhabit the Islands, two are already extinct, 26 are at high risk, nine are in critical danger, 26 are in a state of vulnerability and 40 are out of danger .
In 2007 it was determined that within the species of plants inhabiting the Galapagos islands, there are 20 that are in critical condition, four of them are in the inhabited islands, where the tourism takes place.
In this way, the main threat to endemic species of freshwater turtles is the introduction of new invasive species of both plants and mammals.
On the other hand, the typical species of marine fauna of the islands are at risk due to the human activity. In this way, dolphins, fish, whales, pinnipeds, marine reptiles and sharks are at risk of disappearing due to activities related to tourism and climate change.
In 2007, it was determined that 6% of Galapagos marine species are at critical risk of extinction, 13% are at high risk and 31% are in a state of vulnerability (EEC, 2017).
References
- BLAKESLEE, S. (December 14, 2015). The New York Times . Retrieved from Scientists Hope to Bring a Galápagos Tortoise Species Back to Life: nytimes.com.
- Eaton, C. (April 7, 2015). Ecoventura . Obtained from Endangered Species in the Galapagos: ecoventura.com.
- (2017). Earth's Endangeres Creatures . Obtained from Endangered Species Search by Area Selection: earthsendangered.com.
- GARZÓN, H. (August 17, 2016). ABC Society . Obtained from First extinction of a bird in the Galapagos Islands: abc.es.
- (March 12, 2017). Species . Obtained from Tortuga Galapagos: islasgalapagos.co.
- (November 8, 2008). Animal in danger of extinction . Obtained from Marine iguana (Amblyrhynchus cristatus): animalesextincion.es.
- (2017). Quasar . Retrieved from"GALAPAGOS ANIMALS AND WILDLIFE: quasarex.com.