The job of the Galpagos tortoise in an ecosystem is the same as the niche of the large herbivores such as sheep, cows, and horse. During the dry seasons they climb the mountain to feed on the moist grass, during the other season they go down the mountain slopes to feed on grass. Although the population of Galapagos tortoises are extinct and are not in there natural habitat due to it. When they were plentiful young tortoises and eggs were preyed upon. This form of mutualism between tortoises and small birds, allow for the birds to prey on the parasites and the tortoises are rid of them.