June 28, 2015
A group of 201 tortoises were repopulated to Santa Fe Island, marking
the first time tortoises have roamed the island in more than 150 years..
On the morning of Saturday, June 27, 2015, the Galapagos National Park Directorate (GNPD) of the Ministry of the Environment and personnel of Galapagos Conservancy initiated the repopulation of Santa Fe Island with giant tortoises. The original tortoises of Santa Fe, Chelonoidis sp., went extinct more than 150 years ago due to exploitation by humans. The return of giant tortoises to Santa Fe is a milestone in conservation, using a new methodology for the ecological restoration of the archipelago.
The GNPD carried out this project in collaboration with Galapagos Conservancy as part of the bi-institutional Giant Tortoise Restoration Initiative. To achieve the project goal of establishing a reproductive tortoise population to fill the historical role of ecosystem engineer on Santa Fe, 201 juvenile Española tortoises (Chelonoidis hoodensis), with similar morphology and genetically similar to the extinct Santa Fe tortoise, were released.
The tortoises, reared in the Fausto Llerena Tortoise Center on Santa Cruz, range between 4 and 10 years of age. In preparation for their release on Santa Fe, the tortoises were measured, weighed, and marked with a microchip, which will facilitate future monitoring. Radio-telemetry transmitters were attached to 30 of the larger tortoises; this will provide dispersal data over the next approximately two years.
The day’s work began at 4 AM when a group of Park rangers and scientists transported 201 tortoises from the Tortoise Center to the Sierra Negra, the GNPD’s research vessel. The Sierra Negra left port at 5 AM, and traveled from Academy Bay in Puerto Ayora to Santa Fe in an hour and a half.
“More than twenty-five park rangers transported the tortoises from the coast to the central zone of the island where they were released, approximately three kilometers from the coast,” said Danny Rueda, Director of Ecosystems of the GNPD. Watch video of the release.
An important part of the Project, added Rueda, is the evaluation over time of ecosystem changes due to the presence of the tortoises, as well as the interaction between tortoises and land iguanas, especially for shared resources such as food.
“The use of an analog species (the Española tortoise) that can replace the original extinct species (the Santa Fe tortoise) is a new approach for ecosystem restoration in Galapagos and can provide a model for the world,” said Dr. Linda Cayot, Science Advisor for Galapagos Conservancy.
During the 18th and 19th centuries, the population of giant tortoises on Santa Fe were devastated by pirates and whalers. Located in the center of the archipelago, Santa Fe covers 9.5 mi2 (24.7 km2). In 1971, the GNPD eradicated the introduced goats. A survey of the island in 2011 indicated an Opuntia cactus population of approximately 250,000, mostly adults, and some 6,500 land iguanas (Conolophus pallidus).