This grassland was once covered by thick forest.
Between Man and Goat
We know from the Galápagos Conservation Trust that there are 13 introduced species of mammals in the Galápagos.✻ The one that has caused the most damage is the goat. Whalers, pirates, and fishers, who were looking for a steady source of meat, introduced goats to the islands in the 1850s. With no island predators and the ability to breed twice a year, the goats grew quickly on Floreana,Santa Fe, Española, San Cristóbal, Isabela, Pinta, and Marchena. By the late 1990s, the total goat population had reached six figures.
Goats are known for their appetites. Over time, they ate their way through large swaths of land on many of the islands. The goats ate the same things the tortoises ate, right down to the tortoise’s go‑to food, the prickly pear cactus.
✻ Bats and rice rats are the only mammals native to the Galápagos Islands.
Taking Back the Islands
Once an invasive species takes over, how do you get rid of it? There’s no single, direct method. Galápagos farmers fight the blackberry one plant at a time. They rip them out by hand.
Tackling the goat problem was another matter. The danger was clear: The goats had grazed the islands mercilessly. Their presence was causing erosion and threatening the survival of rare plants and trees. Key endemic species, like the giant tortoise, were at risk. The goats had to go. Project Isabela was enacted in 2004. Tens of thousands of goats were killed on Isabela. It was an extreme solution, but one deemed necessary to protect the islands. As the goats disappeared, plant and animal life on the islands rebounded.
a herd of goats on Isabela Island
Invasive species pose a real threat to the islands. Each introduced species must be monitored and managed to protect the islands.
Goats eat plants like prickly pear cactus, which is food for giant tortoises, land iguanas, doves, cactus finches, and mockingbirds.