Will Last Galapagos Giant Tortoise Reproduce?

Lonesome George Mates Again as Home Island of Pinta is Restored

Aug 10, 2009

The famous surviving giant tortoise of the Galapagos has mated again but reintroduction plans for Pinta Island, once damage is repaired, may involve another subspecies.

2009 is the 50th anniversary of the establishment of the Charles Darwin Foundation and Galapagos National Park. The successful hatching of eggs sired by the last Pinta Island tortoise (Geochelone nigra abingdoni) would be the perfect gift. But scientists from the Giant Tortoise Center for Reproduction and Captive Breeding won’t know whether this year’s eggs are fertile until November.

Galapagos National Park Attempting to Save Giant Tortoise Subspecies From Extinction

The Giant Tortoise Center for Reproduction and Captive Breeding is a program of the Galapagos National Park. At the Center, Lonesome George, the Pinta Island giant tortoise is housed with two female Isabela Island tortoises (Geochelone nigra becki) in hopes that he will reproduce.

Until last year, Lonesome George had not shown any interest in breeding. Then, in 2008, the Galapagos giant tortoise, believed to be between 90 and 110 years old, mated. Unfortunately, the eggs proved to be infertile. And that is the worry for this year as well. In the meantime the five precious eggs have been removed from the nest and taken to the Center for Reproduction and Captive Breeding where they are being kept in an incubator at 29.5ºC to ensure that any eggs that hatch will be female.

Restoring Pinta Island’s Biodiversity Includes Galapagos Tortoises

Whalers harvested the giant tortoises from Pinta Island until Lonesome George was the last Galapagos tortoise left on that island. He was taken into captivity in 1972. Once the tortoises were gone, fishermen introduced goats, whose grazing caused serious damage to the island’s ecosystem. In 1999 the goats were eradicated from the island and the vegetation has begun to recover.

It seems, however, that the Galapagos giant tortoise played a valuable role as a seed disperser on the island, as well as grazing in a way that allowed Pinta’s native vegetation to flourish. In the absence of other members of the Pinta Island subspecies, the Galapagos National Park has decided that the Espanola island tortoise (Geochelone nigra hoodensis) may be the best choice for repopulating Pinta.

Being the most closely related to Lonesome George and having been successfully bred and reared in captivity by the Park and the Charles Darwin Foundation, this Galapagos island tortoise subspecies are a good choice for protecting the now restored Pinta Island’s natural vegetation.

The Future of Galapagos Island Tortoises

While hopes may be dimming for saving the Lonesome George's subspecies of Galapagos island tortoise, the remaining eleven other subspecies, separated for many years on different islands, are likely to benefit from what has been learned through the work of the Charles Darwin Foundation over the last 50 years. And there has been some suggestion that Lonesome George be moved home to Pinta. The results of this year’s breeding attempt will likely have an effect on that decision.

The copyright of the article Will Last Galapagos Giant Tortoise Reproduce? in Endangered Species is owned by Dawn M. Smith. Permission to republish Will Last Galapagos Giant Tortoise Reproduce? in print or online must be granted by the author in writing.

Sep 8, 2009 7:00 PM

Guest :

I saw some of the giant tortoises a few years ago on St. Helena Island, where Darwin had dropped them off. Amazing to think of the connection to Darwin right there wandering on the lawn, slowly, of course. The last of the original ones, I think, recently died. Would they be a source of DNA?
Pauline Dolinski