 By the early 1970s , it was uncertain whether the kakapo was still an extant species . At the end of 1974 , scientists located several more male kakapo and made the first scientific observations of kakapo booming . These observations led Don Merton to speculate for the first time that the kakapo had a lek breeding system . From 1974 to 1976 , 14 kakapo were discovered but all appeared to be males . This raised the possibility that the species would become extinct , because there might be no surviving females . One male bird was captured in the Milford area in 1975 , christened " Richard Henry " , and transferred to Maud Island . All the birds the Wildlife Service discovered from 1951 to 1976 were in U @-@ shaped <unk> valleys flanked by almost @-@ vertical cliffs and surrounded by high mountains . Such extreme terrain had slowed colonisation by browsing mammals , leaving islands of virtually <unk> native vegetation . However , even here , stoats were present and by 1976 the kakapo was gone from the valley floors and only a few males survived high on the most inaccessible parts of the cliffs . 
