 Another aspect of the kakapo 's breeding system is that a female can alter the sex ratio of her offspring depending on her condition . A female who eats protein @-@ rich foods produces more male offspring ( males have 30 % – 40 % more body weight than females ) . Females produce offspring biased towards the <unk> sex when competition for resources ( such as food ) is high and towards the non @-@ <unk> sex when food is plentiful . A female kakapo will likely be able to produce eggs even when there are few resources , while a male kakapo will be more capable of perpetuating the species when there are plenty , by mating with several females . This supports the <unk> – Willard hypothesis . The relationship between clutch sex ratio and maternal diet has conservation implications , because a captive population maintained on a high quality diet will produce fewer females and therefore fewer individuals valuable to the recovery of the species . 
