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 trees or on the ground during the day and moves around its territories at night. Though the kakapo cannot fly, it is an excellent climber, ascending to the crowns of the tallest trees. It can also "parachute" – descending by leaping and spreading its wings. In this way it may travel a few metres at an angle of less than 45 degrees. With only 3.3% of its mass made up of pectoral muscle, it is no surprise that the kakapo cannot use its wings to lift its heavy body off the ground. Because of its flightlessness, it has very low