Species-saving Tortoise will be Released Back into the Wild
Wed, April 21, 2021

Species-saving Tortoise will be Released Back into the Wild

Tortoises are particularly distinguished from other turtles by being land-dwelling, while many other turtle species are at least partly aquatic / Photo Credit: Magda Ehlers via Pexels

 

Diego, the giant tortoise, is going back into the wild after single-handedly saving his species from extinction—thanks to his unstoppable libido.

After about 40 years of breeding, Diego is going back to his native island of Española in March with 14 other adult tortoises. The 100-year-old tortoise was part of a breeding program that sought to boost the population of their species on Santa Cruz Island in the Galapagos, Ecuador.

Authorities commended Diego, saying the womanizing tortoise was responsible for a significant percentage of the island's new tortoise population.


Saving his species

The Galapagos National Parks service (GNPD) believes Diego originated from the Galapagos in the first half of the 20th century during a scientific expedition. After this, the tortoise was brought to the San Diego Zoo and lived there for several decades before joining the breeding program in the mid-1960s.

At the time, the total global population of the species was only 15 known mature adults of Diego's species (Chelonoidis hoodensis), 12 females and three males, according to the International Union for Conservation of Nature (IUCN). Those tortoises were also too spread out to reproduce, with one being at the San Diego Zoo.

But since the breeding program, the island saw an immense boost in population of up to over 2,000—about 40% of which are because of Diego. The 100-year-old tortoise is said to be the father of over 800 tortoises from the breeding program.

"About 1,800 tortoises have been returned to Española and now with natural reproduction, we have approximately 2,000 tortoises," Jorge Carrion, the park's director, told AFP. "This shows that they are able to grow, they are able to reproduce, they are able to develop."

 

Tortoises are reptile species of the family Testudinidae of the order Testudines / Photo Credit via Pixnio

 

The GNPD said Diego will now return to his original home after nearly eight decades. Carrion said, "there's a feeling of happiness" to be able to return the tortoise to his natural habitat.

However, Diego must first undergo a quarantine period before going back to Española to avoid carrying seeds from plants that are native to Galapagos' land.


Maintaining the population

The Chelonoidis hoodensis has come a long way since the breeding program to save the species began. In 2014, there were already 1,900 that were returned to their original habitat—out of which 50% have survived. Since 1975, the IUCN said a total of 1,837 have been returned to Española and reproduction was first observed in 1990.

According to the IUCN, the current population varies from 11-20% of on-site recruitment—meaning repatriated tortoises comprise 80-90% of the population.

"The success of this program is also demonstrated by genetic analyses, which indicate that while none of the tortoises sampled in 1994 had hatched on the island, of those tested in 2004 and 2007, 3% and 24% were [on site] hatchlings, respectively" the conservation organization added.

Washington Tapia, director of the Giant Tortoise Restoration Initiative (GTRI) in Galapagos, said the island can maintain the tortoise population as per mathematical models with different possible scenarios for the next hundred years. He noted that the population will continue to grow normally even without any returning new hatchlings.

 

 

Meanwhile, Carrion said the GNPD has implemented actions for the ecological restoration of the island on top of increasing the giant tortoise population. These actions include the eradication of introduced species and the regeneration of cacti through the Galapagos Verde 2050 project—both of which have helped uphold the island's ecosystem to have the proper conditions to support the growing Chelonoidis hoodensis population.


Lonesome George

The story of Diego's contribution to his species' population growth is truly remarkable. However, not all tortoises held the same fate as him.

For the Chelonoidis abingdoni species, their hope of being saved from extinction faded when a giant tortoise known as Lonesome George refused to breed while in captivity.

Lonesome George was the last known member of his species and was also part of the breeding program to restore their population. Decades of mating attempts bore nothing for his kind as he failed to produce any descendants and died in 2012.

"Only when George had died did an autopsy reveal it wasn’t lack of potency that impeded his reproduction, but a more anatomical ailment affecting his reproductive organ," the New York Times reported in 2017, as per the Washington Post.

The complete and near-extinction of the Chelonoidis hoodensis and Chelonoidis abingdoni came about when whalers, colonists, and other travelers began hunting them for food as they passed through the islands. Their numbers continued to dwindle when settlers introduced goats, which the Washington Post said lessened the cacti that giant turtles need for food, water, and shade.

 

 

Scientists began the restoration of the tortoise population in 1965 through the GTRI back to their historical numbers—the program that brought Diego to popularity not only to his species but also among tourists.

"It’s not just that he has a name and a story," James P. Gibbs, a professor of environmental and forest biology at the State University of New York in Syracuse, told the Washington Post.

"He is a very distinctive tortoise. He has this very bold personality, kind of broken scutes, a big yellow neck. He’s just an out and about the tortoise," added Gibbs, who also assisted in the breeding program.