 Goat eradication on islands, including Pinta, was achieved by the technique of using "Judas" goats with radio location collars to find the herds.Marksmen then shot all the goats except the Judas, and then returned weeks later to find the "Judas" and shoot the herd to which it had relocated.Goats were removed from Pinta Island after a 30-year eradication campaign, the largest removal of an insular goat population using ground-based methods.