Kakapo than females. Twenty-eight males were found to average in one study, and 39 males were found to average in another. In the same studies, 28 females were found to average and 18 females were found to average , respectively. Kakapo are the heaviest living species of parrot and on average weigh about more than the largest flying parrot, the hyacinth macaw. The kakapo cannot fly, having relatively short wings for its size and lacking the keel on the sternum (breastbone), where the flight muscles of other birds attach. It uses its wings for balance and to break its fall when
Kakapo at approximately 10 to 12 weeks of age. As they gain greater independence, their mothers may feed the chicks sporadically for up to 6 months. Because the kakapo is long-lived, with an average life expectancy of 60 (plus or minus 20) years, it tends to have an adolescence before it starts breeding. Males start booming at about 5 years of age. It was thought that females reached sexual maturity at 9 years of age, but four five-year-old females have now been recorded reproducing. The kakapo does not breed every year and has one of the lowest rates of reproduction among