Expedition to Wolf Volcano to Search for Tortoises

January 12, 2015

Home of the hybrid tortoises with lineages from Pinta and Floreana Islands 

By Wacho Tapia, Director of the Giant Tortoise Restoration Initiative (GTRI)

Wolf volcanoWolf is the highest volcano in the Galapagos Archipelago, and one of the most challenging for field work due to its complex and capricious topography. My first experience with this beautiful and difficult volcano was in December 2008 when, as part of the technical team of the Galapagos National Park, I organized and led one of the largest scientific expeditions in Galapagos in recent years. Approximately 50 people participated in it, distributed in 10 separate camps, including park rangers, scientists, and logistical support staff. Those in logistical support — people who are normally invisible to the outside world — displayed tremendous physical capacity as they constantly transported food and water to the remote camps. In spite of the hostile terrain, huge and painful blisters on their feet, thirst, fatigue, and the inclement equatorial sun, they fulfilled their mission to ensure the safety and well-being of the rest of the team.

So before recounting tales of this most recent trip, I want to thank Novarino Castillo and his team, without whom we would never have collected blood samples from more than 1,600 tortoises in 2008. Genetic analyses of those samples at Yale University identified 17 hybrid individuals with genes of the recently extinct Pinta Island tortoise, and more than 80 individuals with genes from the Floreana Island tortoise — an island where tortoises have been extinct for 150 years. This provided us with the opportunity to recover these two lineages and repopulate their islands.

This past December, I returned to Wolf Volcano accompanied only by Dr. James Gibbs of SUNY-ESF and two Galapagos National Park rangers, Jeffreys Málaga and Carlos Vera. Camping at the coast this time, we had to cross a 4-km stretch of rough a’a lava each morning to start the climb to tortoises. Working in teams of two, we searched for tortoises, guided by GPS points of where hybrid individuals were encountered in 2008.

Cactus on Wolf Volcano

One delight of this trip was to witness the recovery of the vegetation resulting from Project Isabela and the successful eradication of goats from northern Isabela Island. In 2008, only a couple of years after the eradication, the area remained completely open and poorly vegetated. In 2014, we found a dense forest covering the slopes. In spite of the difficulty of making a path through the forest with our machetes, it was gratifying to see that ecological restoration is occurring — not only on Wolf Volcano, but throughout the entirety of Isabela Island.

Our first day searching for tortoises was frustrating. Despite having covered a large area, we only found a few individuals; perhaps because the vegetation was dry and there was little available food. On the second day, we climbed to the highlands in search of better habitat. After passing 200 m in elevation, the vegetation began to change from dry shrubs to trees, with green herbaceous plants growing in the understory beneath the canopy.

Around 11 AM, just above 400 m, a light rain began to fall. As we climbed on, the rain intensified and soon small streams flowed down the steep slope. Then something spectacular happened: we began to see traces of tortoises heading downslope. But we only saw footprints; no actual tortoises. We climbed another two hours to 800 m, where several hybrid Pinta and Floreana tortoises had been tagged in 2008. We still found none.

With persistent rain and no tortoises in sight, we began the long hike back down the mountain. This time we followed the fresh tortoise tracks, which helped us unravel the mystery. The tortoises had indeed gone to the highlands during the drought in search of food, but with the first sign of rain, they began their migration down the mountain to an area where rainwater temporarily accumulates.

Tortoises on Wolf

At approximately 300 m, we found a gully where, even with little precipitation, the water collects in pools where tortoises can drink. Dozens of them were spread out all along the gully taking advantage of the water source, from 300 m down to 28 m, near their nesting zone. We were running out of daylight, so we quickly tagged and sampled those with semi- and full-saddleback shells — the typical form of Floreana and Pinta tortoises — and then hurried back to camp with the last vestiges of light.

Returning to the same area the next day, we were thrilled to discover many tortoises, several of them strongly saddlebacked, suggesting high percentages of genes from Pinta or Floreana tortoises. We collected more blood samples and must now wait for the genetic analysis to provide results.

A tortoise drinking water on wolf.

After only a few days of very hard work with long hikes over rough lava, both Jeffreys’ and my boots were destroyed. Exhausted, we all experienced intense pain from blisters. But the trip had been successful. We could re-locate hybrid tortoises identified in 2008, and had found many previously unmarked tortoises with a shell-shape similar to the Pinta and Floreana lineage. We are now ready to plan the major expedition to Wolf Volcano later this year to expand the blood sampling work even further, and to collect as many of the Pinta and Floreana hybrids as possible to begin the breeding programs for the two islands.

Wolf Volcano is spectacular, especially for people like James, Jeffreys, Carlos and myself, who love nature. Each day back at camp, we were greeted with such wonders as flightless cormorants in a courtship dance, marine iguanas, and penguins — all sharing a patch of lava close to the sea. And every day ended with a spectacular sunset and with our cameras we were able to  capture the sun in our hands. 

Wolf sunset, marine iguana, and penguin.

 All photos © W. Tapia and J. Gibbs

 

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  1. Heartening and inspiring! The photo of the tortoise drinking from the mud puddle reminds me of the Isla Isabela road to the Wall of Tears, which, because it is made of mixed clay and sand, will hold rain water. If you stand on the road and rain begins, you hear a constant rustling in the woods, drawing ever nearer. Then tortoises appear from the brush, and contend with one another to drink from the mud puddles. It is a great sight, seeing these released animals from the local tortoise rearing station, encountered in the wild, making good use of a human-imposed intrusion.

  2. Thank you for this exciting work. I really admire your persistence and commitment to tortoise conservation in Galápagos.

  3. As genetic based scientific discoveries continue to unfold, perhaps it is prudent to avoid populating islands with tortoises that are not of the genetics of that specific island. There have been many scientists who argued against releasing non-Pinta tortoises onto Pinta, and other islands.
    And now that genetically closer Pinta tortoises have been found to exist, what will be done with the tortoises already released onto Pinta island? It is not like they can be quickly rounded up…and then what?

    • Hi Heidi- Hopefully this will help clear things up. The potential for partial Pinta tortoises was known at the time of the release of the 39 tortoises onto Pinta in May 2010. For that reason, those tortoises were sterilized prior to release. This served several purposes – all approved by the Galapagos National Park Directorate: 1) It allowed hybrid tortoises from relatively healthy tortoise populations, tortoises that had been in captivity since birth, to live their lives out in the wild instead of in captivity; 2) it eliminated the cost to the GNPD of maintaining those tortoises in captivity for perhaps another 100 years or more, and 3) it placed adult tortoises onto Pinta only a few years after the removal of the last goat so that they could have a positive, natural impact on the recovery of the vegetation, while the Galapagos National Park Directorate and its collaborators moved forward with plans to eventually release tortoises with genetics closer to the original Pinta tortoise. The sterilizations eliminated the problem of potential reproduction between those tortoises released in 2010 with tortoises with Pinta genes to be released in the future.

  4. Pingback: Galapagos and Beyond: April 2015 Roundup | Galapagos Conservancy

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