WorldWide Tech & Science. Francisco De Jesùs.
Ecuador: The Galapagos lslands, the great refuge of Giants.
Despite the Galapagos Lonesome George the last of the Galapagos Geochelone abigdoni species died last week, still survive another ten species of giant Galapagos that need attention to prevent its disappearance. The records also mention one other species, which inhabit the Aldabra island in the Seychelles archipelago, located in the Indian Ocean.
The Galapagos National Park (PNG) recognizes fourteen species originate. Three of which were extinct before the death of George. Of those three, two were eliminated due to human action and volcanic eruptions.
Now there are five species in the volcanoes of Isabela Island and the other five are spread over the whole archipelago, which owes its name to these giants, known as Galapagos. There are an estimated 15,000 to 20,000 turtles.
Scientists who study these giants believe that, over a century ago, there were about 200,000 turtles. The turtles were part of the studies of Charles Darwin in the nineteenth century, when verified his theory of evolution of species through natural selection. At that time identified that the shells of these reptiles were variations from one island to another.
The Buccaneer (known as pirates) and the whalers were in the beginning, the main predators of giant tortoises (and other native species) during the seventeenth and eighteenth centuries, according to the writings of the time, which reflect part of the letters of travelers.
At that time, most of the turtles were used for food during the long trips were the buccaneers and whalers. They were uploaded (taken from the wild) and carried live on boats and provisions, and that turtles could be twelve months without eating and without drinking six months.
The size and weight of giant also influenced to consider them human food. Their size reached up to 1.50 meters and its weight was over 200 kilos. Others used them to collection (trim) or as trophies.
Through the diaries of the past century whaling is estimated that between 100,000 and 200,000 turtles were captured in less than 50 years. Most food served.
On these trips, some turtles were moved from one island to another. And in those same crossings were introduced several species of animals such as goats, rats, ants, pigs, donkeys, dogs, which later ended up with multiple numbers of giants, with their young and to the environment.
Estimated population of turtles: (1995-2009)
It was a second predation, also caused by man. Some animals, eg pigs or swine, destroyed turtle nests and ate the eggs and the young ones.
Along with the consumption of the giant animals entering the habitat destroyed, then competing for the same territory as the goats. They obliterated the existing plants and vegetation, which were the food of turtles.
The land of George, the Pinta, is an example of this destruction. One example will suffice. There, in 1959 introduced two goats and ten years later the number reached 5,000. That meant that the land would be left deserted. It was the survival time among animals.
George managed to survive. The American biologist Joseph Vágvölgyi saw the December 1, 1971, says the official information from the Galapagos National Park (PNG). Thus was organized the rescue. In 1972 it moved from its desert land to the Charles Darwin Research Station on Santa Cruz Island.
From then intensified studies and projects that were to save the turtles. Earlier in 1960, became operational programs and breeding in captivity. This, after Ecuador declared in 1959 to 97% of the archipelago's land area as National Park.
George was always the inspiration of local and foreign community in the 40 years of its existence was known. It was international image. His story has inspired writers, scientists, literary and film ...
And while this was happening, repopulated their relatives on other islands. For example, the Spanish were only two males and twelve females in 1960, after razing goats with existing vegetation and change the type of soil.
These survivors were taken to captivity for breeding. They were joined by another male, Diego, of the same species, which was in a U.S. zoo Half a century later see results. In Spanish there are about 1,000 turtles.
How are you giants live between 100 and 150 years, the results are long term, because reproduction is slow, says Linda Cayot, American scientific organization Galapagos Conservancy, dedicated to the study and conservation. She came to the islands in 1981 for a doctorate (PHD) on turtles of Santa Cruz and Pinzon.
Cayot met George in that year and had direct contact with this giant from 1988 to 1997. It was part of the team that tried to play the survivor of Pinta.
The researcher says that now the giant turtle populations are in better condition than when it started the National Park, but there is still "much to do." One achievement was the eradication of some species such as goats and pigs, and the restocking of certain species.
Consider that there are now between 10% and 20% of the original number of giants. But the problem is not just copies. But the reconstruction of the countryside.
For example, in the Spanish island still have problems with the recruitment of vegetation such as cacti, the main food of giant, which was exterminated by the goats.
On the island Pinzon, however, introduced black rats still do not allow the repopulation of the turtles.
On Isabela Island, in the area of Wolf volcano was discovered that there are many hybrids, after the blood of more than 1,600 turtles. It is believed that the whalers took the turtle from one island to another. There were species with "some genes" Pinta Island. And about 80 turtles lineage (nearly 50%) of the species from Floreana, believed had disappeared completely in 1850. Scientists still hope to find pure turtles in Wolf volcano, because hybrids are an average of 20 years. That is, there is the possibility that their parents "pure" are still alive.
It is difficult to know the exact age of each turtle, as the case of George. Estimates can be made with the plates (the lines on the plates) to ten years indicates Cayot. "More than ten years can tell if young, adult or old. Turtles probably live to 150, perhaps 200 years. But we will not know it for sure until the turtles die in captivity, not produced in our lifetime, "he adds.
Timeline: Rescue of species
1960 to present
They start breeding programs for captive giant tortoises. Just as the extermination of introduced species. The first island including Pinzon was devastated by black rats. In 1978, the islands were declared a Natural Patrimony of Humanity.
1993 - 2012
Two females arrive on the island Isabela George to keep him company. The aim was to play. Were fifteen years. The eggs were infertile were achieved. In 2011 changed the companions of George. They were from the Spanish island. There was also no offspring.
2007-2008
The researchers identified a tortoise on Isabela Island had 50% of the genes of the Pinta tortoise. It was a first-generation offspring.
January 2012
A study from Yale University, USA, announces the discovery of genes Chelonoidis elephantopus, thought to be extinct. This after finding genetic traces of the species into the DNA of their hybrid offspring.
