There are two subspecies of the Galapagos giant tortoise (Chelonoidis nigra) – not just one, as had been long believed – living on the island of Santa Cruz in the Galapagos Archipelago, says a team of scientists led by Dr Gisella Caccone of Yale University.
The Eastern Santa Cruz Tortoise (Chelonoidis nigra ssp. donfaustoi). Image credit: Washington Tapia.
Two main populations of giant tortoises are known to inhabit the island: a large population on the west side in an area known as the ‘Reserve’ and another on the lower eastern slopes around a hill named ‘Cerro Fatal.’
A new genetic and morphological study, published in the journal PLoS ONE, has revealed that the two populations are much more distinct from each other than previously thought, and should be recognized as separate subspecies: the Western Santa Cruz Tortoise (C. n. ssp. porteri) and the Eastern Santa Cruz Tortoise (C. n. ssp. donfaustoi).
“This is a small and isolated group of tortoises (Eastern Santa Cruz Tortoises) that never attracted much attention from biologists previously,” said Dr James Gibbs of the SUNY College of Environmental Science and Forestry, a team member and a co-author on the study.
He added: “but we now know that they are as distinct as any” subspecies of the Galapagos giant tortoise.
“Their discovery and formal description will help these tortoises receive the scientific and management attention they need to fully recover.”
The scientists named the new subspecies of tortoise in honor of longtime Galapagos National Park ranger Fausto Llerena Sánchez, known to his friends and colleagues as Don Fausto.
“Don Fausto dedicated 43 years to giant tortoise conservation as a park ranger for the Galapagos National Park Directorate,” Dr Gibbs said.
“He was the primary caretaker at the Tortoise Breeding and Rearing Center on Santa Cruz, which now bears his name. The restoration of several tortoise populations is due in part to Don Fausto’s dedication and efforts.”
“It’s to honor Don Fausto for all his dedication and hard work,” Dr Gibbs said.
“He devoted his life to saving many critically endangered tortoises through captive breeding. It isn’t easy to breed tortoises in captivity. He didn’t have many resources or much guidance. He figured it out through patient observation, great creativity and intelligence, and tremendous resourcefulness.”
“Don Fausto successfully bred tortoises in Galapagos while many of the best zoos around the world have failed in their efforts to do so.”
“I recall many times seeing Don Fausto early on a Sunday morning, when most everybody else was still asleep, riding his bike to the captive rearing center to tend to the tortoises. His dedication to his work has been inspirational,” Dr Gibbs said.
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Poulakakis N. et al. 2015. Description of a New Galapagos Giant Tortoise Species (Chelonoidis; Testudines: Testudinidae) from Cerro Fatal on Santa Cruz Island. PLoS ONE 10 (10): e0138779; doi: 10.1371/journal.pone.0138779
