At least seven of the nocturnal parrots have died in recent weeks, suffering from a respiratory infection caused by a common airborne fungus.
With just 142 adult kakapos alive in the wild, scientists have asked for donations to help move the surviving birds to a safer area.
The birds have to be helicoptered out of their remote island homes for treatment on the mainland.
"Kakapo need our urgent support. We are currently managing an aspergillosis outbreak affecting many of the kakapo on Whenua hou," the Department of Conservation said in a statement.
"Detecting and treating birds with this potentially fatal disease is extremely difficult. Birds are flown by helicopter to mainland New Zealand for CT scans, and if affected face several months or more of intensive treatment."
Scientists have shared their upset over the outbreak on Twitter.
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Outpouring of donationsKakapo supporters have donated at least NZ$100,000 ($66,000 or €58,000) to help their recovery, with more than half of donations coming from overseas.
At least 36 have been sent to veterinary hospitals with suspected cases, local media reported. Nine of those have reportedly been given the all clear. Seventeen are being treated for aspergillosis, Radio NZ reported.
More than 100 scientists helped ensure the successful breeding season, with the remaining 50 females producing 249 eggs, of which 77 successfully hatched.
The population reached a nadir last century when numbers of living parrots hit just 50, thanks to predation by introduced species. They have bounced back due to isolated, predator-free islands.
The birds typically only mate every two to four years when the native rimu trees are full of fruit.
aw/msh (dpa, AFP)
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