THE GENTLE GIANTS OF THE GALAPAGOS: TORTOISES, PART 2: RESURRECTION?

Last week’s post introduced my encounters with the Galápagos Islands eponymous tortoises.  Yet, without the intense efforts of scientists and conservationists, I as well as the rest of the modern world might not have even seen these iconic creatures other than in museums or books. As I noted, the first humans to land on the islands discovered that the tortoises have sweet meat, are easy to catch and can last for long periods without water, making them perfect food for long voyages. Sadly their uncontrolled rapacious and selfish exploitation killed almost 200,000  tortoises and ultimately caused the extinction of  3 separate species of long-necked saddlebacks.

In 1972 a sole member of a fourth saddleback species was discovered on the tiny Pinta Island:

This was Lonesome George.  Naturalists and scientists set up an expansive home for LG at the Charles Darwin Research Station in Puerto Ayora on the island of Santa Cruz (more about the center later) and for 40 years tried in vain to find him a mate.  LG was over 100 years old when he died, unfulfilled in June of 2012, and a fourth species of saddlebacks was thought to have joined the growing ranks of the extinct.

This is George:

Scientists were devastated when George died –  sometimes tortoises can live up to 150 years – they had hoped he would live long enough for them to find LG a mate. Yet, fantastically all hopes to propagate this species were not lost.

The Charles Darwin Research Station was established to protect the unique but precarious flora and fauna of the Galápagos Islands. One of the first campaigns of the center was a review of the tortoise population and it was determined that 11 out of 15 original species still remained on the islands and most of them were in danger if imminent extinction .  Fortunately the long life span of the tortoises gave the scientists some additional time to work on conservation and potential repopulation.

Within the vast research station is the Faust Llerena Tortoise Center which has a sole goal to save the giant tortoise population.  Its efforts have been phenomenal – over 4000 young tortoises from 8 species have been reintroduced to their origin island.  I was fortunate to see first hand the hatchlings, juveniles and full-grown adult tortoises thriving at the center.  The age of a tortoise can be determined, kind of in a reverse order than tree rings.  The younger tortoises have clearly defined circles on their shells:

The circles fade over time – so the oldest tortoises have barely recognizable circles:

I also learned a fascinating tortoise fact:  they have voracious sex lives. The next section may be a bit NFSW.

Sexual maturity for a tortoise is around 10-20 years of age – and remember they can live up to 150 years. They are polygamous lovers, mating with as many partners as possible.  Mating occurs throughout the year, although the tortoises prefer it when it is hot and humid. Males can take up to 20 minutes per encounter, and females can store sperm for over 4 years after copulation.  One fecund tortoise is said to have sired over 800 offspring.

And the males are quite vocal about it:

Unfortunately, poor Lonesome George did not have any females to sport with so the reintroduction of his species has to rely on science.  Recently, tortoises were discovered on Pinta Island with the same genes as George and were taken to the breeding center on Santa Cruz.   Scientists are now studying the DNA of these tortoises and hope in the near future to start breeding those with the purest “George Genes.”   If all goes well, a new saddleback tortoise population might be released back onto Pinta Island – as soon as within 5 to 10 years – and the species once lost can be revived.

Here’s hoping.

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