Kakapo low. Supplementary feeding affects the sex ratio of kakapo offspring, and can be used to increase the number of female chicks by deliberately manipulating maternal condition. During the winter of 1981, only females lighter than were given supplementary feeding to avoid raising their body condition, and the sex ratio results in 1982 were close to parity, eliminating the male-biased sex ratios in the unrestricted feeding. Today commercial parrot food is supplied to all individuals of breeding age on Whenua Hou and Anchor. The amount eaten and individual weights are carefully monitored to ensure that optimum body condition is maintained. Kakapo
Flightless bird more species of flightless birds (including the kiwi, several species of penguins, the takahe, the weka, the moa, and several other extinct species) than any other such location. One reason is that until the arrival of humans roughly a thousand years ago, there were no large land predators in New Zealand; the main predators of flightless birds were larger birds. Ratites belong to the superorder Palaeognathae birds, which include the volant tinamou, and are believed to have evolved flightlessness independently multiple times within their own group. Some birds evolved flightlessness in response to the absence of predators, for example on