 A key part of the Recovery Plan is the supplementary feeding of females . The kakapo breeds only once every two to five years , when a certain type of plant species , primarily <unk> <unk> ( rimu ) , produces protein @-@ rich fruit and seeds . Observations of the relationship between intermittent breeding and the plant 's mast year help biologists choose which suitable supplementary foods to increase kakapo breeding frequency . In 1989 , six preferred foods ( apples , sweet potatoes , <unk> , Brazil nuts , <unk> seeds and <unk> ) were supplied ad <unk> each night to 12 feeding stations . Males and females ate the supplied foods , and females <unk> on Little Barrier Island in the summers of 1989 – 91 for the first time since 1982 , although nesting success was low . 
