The last member of the Pinta Island tortoise subspecies (Chelonoidis nigra abingdonii) died on June 24, 2012. Known as "Lonesome George" by his keepers at the Charles Darwin Research Station on the Galápagos Island of Santa Cruz, this giant tortoise was estimated to be 100 years old. Weighing 200 pounds and measuring 5 feet in length, George was a healthy representative of his kind, but repeated attempts to breed him with biologically similar female tortoises proved unsuccessful.
Scientists at the research station plan to save tissue samples and DNA from George's body in hopes of reproducing his genetic material in the future. For now, though, Lonesome George will bepreserved via taxidermy to be displayed at the Galápagos National Park.
Characteristics of the now-extinct Pinta Island tortoise resemble those ofother members of the Galapagos giant tortoise species (Chelonoidis nigra), which is the largest living species of tortoise and one of the heaviest living reptiles in the world.
- Dark brownish-gray shell and skin
- Large, bony plates on carapace (upper shell)
- Saddleback-shaped shell
- Thick, stumpy limbs with dry, scaly skin
- Toothless mouth shaped much like a beak
- Long neck
Males could reach 400 pounds, 6 feet in length, and 5 feet in height (with necks fully extended).
Like other saddleback tortoises, the Pinta Island subspecies primarily inhabited arid lowlands but likely made seasonal migrations to more moist areas at higher elevations.
The Pinta Island tortoise's diet consisted of vegetation, including grasses, leaves, cacti, lichens and berries. It could go for long periods without drinking water (up to 18 months), and is thought to have stored water in its bladder and pericardium.
Galápagos giant tortoises reach sexual maturity between 20 and 25 years.
Peak mating season occurs between February and June.
Females travel to sandy coastlines where they dig nest holes for their eggs (saddlebacks like Pinta tortoises typically dig 4 to 5 nests a year with an average of 6 eggs each).
The female retains sperm from one copulation to fertilize all of her eggs.
Incubation spans 3 to 8 months, depending upon temperature.
Nest temperature also determines the sex of hatchlings (warmer nests result in more females).
Hatching and emergence occur between December and April.
Galápagos giant tortoises can live up to 150 years in the wild. The oldest known tortoise was Harriet, who was approximately 175 years old when she died at Australia Zoo in 2006.
The Pinta Island tortoise is extinct (other subspecies of Galápagos tortoise are listed as "Vulnerable" by the IUCN).
Causes of Population Decline
During the 19th century, whalers and fishermen killed Pinta Island tortoises for food, driving the subspecies to the brink of extinction by the mid-1900s.
After exhausting the tortoise population, seasonal seafarers introduced goats to Pinta in 1959 to ensure they would have a food source upon landing. The goat population grew to more than 40,000 during the 1960s and 1970s, decimating the island's vegetation, which was the remaining tortoises' food.
Pinta tortoises were considered extinct until visitors spotted Lonesome George in 1971. George was taken into captivity the following year.
Starting in the 1970s, varied techniques were employed to eradicate Pinta Island's goat population in order to discover the most effective method for later use on larger Galápagos islands. After almost 30 years of only moderately successful extermination attempts, an intensive program of radio-collaring and aerial hunting aided by GPS and GIS technology resulted in complete eradication of goats from Pinta.
Monitoring projects have since shown that Pinta's native vegetation has recovered in the absence of goats, but the vegetation requires grazing to keep the ecosystem properly balanced, so the Galápagos Conservancy launched Project Pinta, a multi-phase effort to introduce tortoises from other islands to Pinta.
How You Can Help
Donate to the Lonesome George Memorial Fund, established by the Galápagos Conservancy to fund large-scale tortoise restoration programs in Galápagos over the next 10 years.