For some time, it was believed that the kea was a polygynous species, with a single male mating with multiple females. That same study, however, noted that there were far more females than males in that particular area. In reality, the kea is monogamous, with couples forming lifelong bonds. These parrots nest in burrows beneath rocks or the roots of trees, digging tunnels up to six metres long leading down to the nest chamber. The female is solely responsible for incubating the eggs and caring for the young chicks, while the male will bring food back for her. The chicks become independent at around four months of age.