Galapagos Islands animals Facts
The famous fable of the race between the tortoise and the hare has seen the tortoise winning. The fable is poignant here; the once extinct Galápagos tortoises are making a comeback on the picturesque Spanish-speaking islands.
A new study released late last month by PLOS One, Demographic Outcomes and Ecosystem Implications of Giant Tortoise Reintroduction to Española Island, Galapagos, mentioned that the Galápagos tortoises are slowly making a return. The islands' ecosystem is so fragile that seeing a tortoise has been considered nearly impossible.
According to the study, in order to save the tortoises from the brink of extinction, groups had to be created. Fourteen Galápagos tortoise populations were started all across the archipelago, but only 11 survived and lived long enough to be rescued by the Galápagos National Park's breeding program and the Charles Darwin Foundation, created in 1959, Nature World News reported.
"We saved a species from the brink of extinction and now can step back out of the process. The tortoises can care for themselves, " James Gibbs, the study's leader at the State University of New York, said.
In the beginning, the giant tortoise (Chelonoidis nigra) once existed in the thousands, between 5, 000 and 10, 000. The tortoises can live for over a century. But by the 1960s the numbers had dropped rapidly, to 15 in total, Time reported. The reason for the tortoises' rapid decline was human exploitation: poaching, and hunting of the tortoises; and, shrinking habitats.
During the 1960s that the giant tortoise became a threatened species. Between 1963 and 1974, conservationists brought over 12 female and three male surviving giant tortoises into captivity. As a result, 1, 500 of their offspring were released into the wild and thrived on their own.
It was not an easy road back from the brink of extinction.
"They were so rare at that point, they couldn't find one another. Many of the females had lichens growing on their backs, and fungi, that indicated they hadn't been mated in a very long time, " Gibbs said according to Nature World News.
The study deemed that the tortoises' recovery has been so successful that humans can step back and let nature take over.
Another factor in the near extinction of the giant tortoises was goats. Almost 100 years ago, goats were introduced into the Galápagos by fishermen as an alternative to meat, Newsweek reported. The problem was that the goats ate everything, including much of the food that sustained the life of the tortoises. The goats turned the islands into dust bowls, but by the 1970s the Galápagos National Park Service staff had killed off all of the goats.
The only thing that thrived were plants such as cacti and woody plants which recolonized the barren land. These types of plants had grown more quickly than grass did.
By trampling woody plants and spreading cacti, tortoises will shift the ecosystem back to its original state, before the goats ever existed, Gibbs predicts. The ecosystem will come back to its more food producing and water efficient cacti - thanks to the tortoises - but it could take another century, Newsweek reported.
Giant tortoises used to live all around the world, but today they only survive in the Galápagos and a group of islands east of Tanzania in the Indian Ocean known as the Aldabra Atoll.