Of the Galapagos: HOW SELECTIVE BREEDING IS HELPING BRING EXTINCT GIANT TORTOISES BACK from the DEAD
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GHOSTS of the Galapagos: HOW SELECTIVE BREEDING IS HELPING BRING EXTINCT GIANT TORTOISES BACK FROM THE DEAD. WORDS AND PICTURES BY: n January 2020, TUI DE ROY / naturepl.com the Giant Tortoise Restoration Initiative mounted I the most ambitious giant tortoise expedition to date. The mission: to find descendants of the long-extinct Floreana and Pinta tortoises, and breed them to help restore these lost bloodlines to their original Galápagos islands. Given the long lifespans of the reptiles in question, only our kids and grandkids will be there to witness the results. ECHOES OF THE PAST Whalers of old collected giant tortoises for food and left a legacy of feral goats and rats that Within the Galápagos archipelago, further depleted tortoise populations. 15 species of giant tortoise have been recognised, although only 11 survive to this day. Which four species are thought to have FLOREANA TORTOISE suffered extinction? already extinct and two But wait! What nobody (Chelonoidis niger) more were reduced to a realized is that sometime mere handful of survivors, during that great tortoise SANTA FE TORTOISE most notably a single male slaughter of the late Pinta tortoise who became 1800s, amid the whalers’ (Chelonoidis nov sp.) known affectionately as shenanigans around Banks About 200 years ago, delicious fresh meat to Lonesome George. Since Bay at the western foot of something really odd hungry sailors. Thus, tens his discovery in 1971, every Wolf Volcano on Isabela happened in Galápagos. - or possibly hundreds - effort was made worldwide Island (where sperm whales It was the heyday of of thousands of tortoises to find him a mate, and tended to congregate), far-ranging whaling met their ignominious to collect his sperm for some captured tortoises enterprises which saw demise. As a side venture, potential breeding with managed to escape. In 1835, Darwin predicted sailing ships venturing Galápagos giant tortoise his nearest kin, but to no Whether they succeeded avail. When Lonesome in crawling over the this species would soon go from both sides of the meat even made it onto to extinct Atlantic to “harvest” vast menus of fancy West Coast George died of natural gunwales, or were tossed numbers of sperm whales restaurants that sprang up causes in June 2012, after overboard (they can swim Known only from bone and frequenting Galápagos in response to the great 40 years in captivity, the pretty well) when the ships egg fragments collected world mourned the passing became overloaded, we in 1905-6 by the California waters. At sea for months California Gold Rush. of an iconic Galápagos will never know. But those Academy of Sciences (CAS) on end, these rugged By the time the plunder emblem. The Pinta tortoise fugitives began cross men soon discovered that abated, of the fifteen FERNANDINA TORTOISE giant tortoises could be species of Galápagos had joined the ranks of its breeding with the natives, stored alive more or less giant tortoises known to extinct Galápagos brethren Chelonoidis becki. (Chelonoidis phantasticus) indefinitely, providing have existed, three were (see sidebars). PINTA TORTOISE (Geochelone abingdonensis) Apparently decimated by volcanic eruptions and known from a single large male also collected by the Lonesome George was the CAS in 1905-6. We know last Pinta tortoise. Despite that whalers had nothing to immense efforts to get do with this species’ demise him to breed, he died because Fernandina’s in 2012 after 40 years in notoriously vast and rugged captivity, without leaving lava fields were simply too descendants. His embalmed much of a barrier for hungry remains are on display in sailors. the Fuasto Llerena Tortoise Breeding Centre, Santa Cruz. ABOVE : The recently rediscovered Fernandina tortoise, believed extinct for decades, brings new hope for the survival of the species. LEFT: Past interbreeding of Wolf Volcano tortoises with extinct ABOVE: Galápagos National Park team takes blood Floreana and Pinta bloodlines led sample from Wolf Volcano giant tortoise. to hybrids which now have the potential to save their species. DNA analysis is used to trace descendants BELOW: Thanks to genetic testing of extinct species, which are then bred for this male was identified as a reintroduction to their original islands. Floreana hybrid — a species thought to be extinct since shortly after Darwin’s visit to the Galápagos — now part of a new breeding Fast forward to 2008, when established rule. Instead program to repopulate the island. I joined an expedition of the mainly domed organized by the carapaces typical of their Galápagos National Park environment, the Wolf tortoise, and a smaller sub- the conservation news: Directorate, tasked with tortoises displayed both group had strong Pinta a wizened little female collecting blood samples shell types, suggesting a tortoise parentage. Fernandina tortoise was from as many tortoises as very unusual admixture Armed with this discovered, surviving was practically possible of genes. A whopping information, park rangers on scant vegetation from the western slope 1,700 blood samples and scientists returned surrounded by impassable, of Wolf Volcano. This - which would take years to Wolf in 2015 to locate barren lava fields on followed a serendipitous to process - were brought and extract some hybrid the western slope of discovery by a team of Yale back from the expedition breeders. A new Floreana Fernandina island. What’s scientists, led by Dr. Gisella for DNA analysis. tortoise captive breeding more, some tracks and Caccone. The team knew When the results were program was initiated in droppings were spotted in that Galápagos tortoises finally tallied, the news 2017, cross breeding those other quasi-inaccessible living in humid climes have shocked and elated the individuals with the highest regions, indicating that dome-shaped shells, while conservation world: a percentage of Floreana she may not be alone. those living in drier habitat substantial number of genes. But Pinta and None had been have ‘saddleback’ shells. ‘saddleback’ type tortoises Fernandina tortoises still seen alive since the But there was something on Wolf Volcano were remained officially extinct. single male collected a unique about the Wolf direct descendants of Then, in February 2019, century beforehand by the tortoises that broke the the long-extinct Floreana another bombshell hit CAS team. This new female had just thrown her species a lifeline. WOLF VOLCANO TORTOISE (Chelonoidis becki) The carapace morphology of tortoises on Wolf Volcano is quite variable, due - as it turns out - to past mating events with individuals from other islands. Hybrids are now scattered far and wide on the rugged western slope of Wolf Volcano. Here, an aggressive display between two males is settled by he whose neck can reach the highest. This often gives the advantage to the more saddlebacked shaped individual, even if he is smaller. a monumental one, each smooth operations. team hiking transects But nature had other through dense tangles ideas. Just 36 hours before of thorny vegetation departure, Fernandina overlaying steep, fractured – which had erupted lava flows in searing heat just three weeks prior – with no locally available registered three major water source. But this seismic events that foretold time, instead of the of another possible near-impossible task of outburst, so this leg of In January 2020 I joined the to scour the forbidding knew that tracking down carrying all equipment and the expedition had to be most ambitious expedition western and northern these rare individuals supplies on our backs, a cancelled at the eleventh ever devised in Galápagos, slopes of Wolf Volcano. wasn’t going to be easy – helicopter was brought in hour for safety reasons (as organized by the Giant The job was to find the but we had an ace up our from mainland Ecuador, it was, no eruption ensued). Tortoise Restoration nearly 100 ‘desirable’ sleeve: on the previous so that boots would hit And when the mother Initiative (GTRI), a joint tortoises that had tested expedition, we’d left the ground ready to work ship (the National Park enterprise between the positive for Floreana and electronic PIT tags in each with no time wasted on launch boat ‘Sierra Negra’) Galápagos National Pinta genes (out of the tortoise’s leg. Scanning logistics. Three more teams approached Banks Bay, Park Directorate and the 1,700 sampled in 2008). these unique ‘barcodes’ would simultaneously laden down with helicopter Galápagos Conservancy, a These individuals would would tell us instantly if a tackle nearby Fernandina and pilot, plus 36 eager US-based NGO. Thirty-six be collected for a captive tortoise had the genes we in hopes of finding a mate expeditioners and gear park wardens, equipped breeding program, helping were looking for. for the recently rescued for 12 far-flung camps, with GPS, satellite phones to restore the lost Floreana Even so, anyone familiar ‘Fantastic tortoise’. The the mountain appeared and electronic tag readers, and Pinta bloodlines to with the terrain on Wolf driest time of year was shrouded in veils of mist were deployed in 12 teams their original islands. We would realize the job was chosen to guarantee and sheets of rain. Undaunted, operations and in the following five but one look at some of the Wolf tortoises, which proceeded in almost days, out of a total of the magnificent males, the we now know subsist in comic chaos. Plans had 2,453 tortoises examined, largest of all saddleback far greater numbers than to be readjusted by the an amazing 29 desirable types, with their incredibly previously estimated. In minute in response to ‘Floreana’ tortoises were long necks and almost addition, careful ever-changing weather identified, recaptured and comically flared shells, is further genetic patterns. As a result, some subsequently airlifted to proof enough of some sort analysis of the teams had to be dropped the waiting Sierra Negra, of Phoenix risen from the CAS Fernandina miles from their intended along with — yes — one ashes of time.