Project Isabela — Galápagos Archipelago-Wide Goat & Pig Eradication

Introduced feral goats had devastated native vegetation on several of the Galápagos Islands' largest islands since the 19th century, out-competing giant tortoises and land iguanas and threatening endemic flora. Project Isabela (1997-2006), led by the Galápagos National Park Directorate and the Charles Darwin Foundation, was funded through a six-year, US$13.3 million Global Environment Facility (GEF/UNDP) invasive-species initiative, with additional support from Galápagos Conservancy and the Frankfurt Zoological Society.

Teams eradicated goats from Pinta (5,940 ha), Santiago (58,465 ha, where more than 18,000 feral pigs were also removed) and northern Isabela (approximately 250,000 ha), combining helicopter-based aerial hunting with radio-collared 'Judas goats' that led hunters to remaining herds, backed by ground teams. Small numbers of goats were deliberately retained short-term as radio-collared Judas animals to locate stragglers before final removal.

A peer-reviewed cost-effectiveness analysis published in PLOS ONE (2011) put the total eradication cost at approximately US$10.5 million across more than 500,000 ha for more than 140,000 goats removed, finding the aerial-based Isabela campaign cost approximately US$9/ha versus approximately US$110/ha for the largely ground-based Santiago campaign. Post-eradication monitoring documented rapid ecological recovery: regenerating tree stumps, expanding highland shrub species, forest tree seedlings and Opuntia cactus populations, and a marked return of Galápagos rails to highland areas in abundance.