Ninety kākāpō chicks were officially added to the population of the critically endangered birds on 1 September, pushing the total to 325 – a record high since recovery efforts began. The world's heaviest parrot, which is also the only nocturnal and flightless parrot, has not had a population exceeding 300 birds in an estimated 75 years.
Record breeding season triggered by rimu berry bounty
This year's record breeding season was triggered by the mass fruiting of the native rimu tree, which produces large numbers of berries every two to four years. After a four-year gap, a bountiful harvest prompted the birds to breed and produce a record number of chicks.
Deidre Vercoe, the conservation department's kākāpō recovery operations manager, said: “The last time the population is thought to have exceeded 300 birds may have been as long as 75 years ago.” She added: “We had a four-year gap between breeding seasons, so it's fantastic to finally see the population increase after all that time.”
Recovery programme battles genetic and breeding challenges
Kākāpō were once abundant across New Zealand, but their population plummeted after the introduction of predators such as cats and stoats. By the 1900s, they were nearly extinct. A recovery programme was established in 1995 with a population of just 51 birds and has battled challenges with genetic diversity, infertility and poor chick hatching rates.
There are three kākāpō breeding populations, all based on predator-free islands off the South Island. Kākāpō breed only every two to four years when the rimu trees produce large numbers of berries, so repopulation is slow. Vercoe noted: “In the early years of recovery, it took 16 years to produce that many chicks.”
Chicks reach independence and join the population
At 150 days of age, the chicks are fledged and considered independent enough to be added to the total population. The youngest chick of the 2026 breeding season was female Awarua-A3, who hatched on 30 March.
Kākāpō are thought to live between 60 and 80 years, can weigh up to 4kg and are famously entertaining. More than 100,000 people tuned in to watch a live stream of a kākāpō sleeping, eating and attending to her nest and chicks during breeding season.
The parrots have unusual mating rituals. Male birds gather in a “lek” to produce a distinctive booming sound, emitted from air sacs in their chests while sitting in a dugout bowl in the ground. The deep boom, which can travel up to 5km, sounds similar to a softly plucked cello string. After choosing a partner and mating, females typically lay one to four eggs. The females become solely responsible for their eggs and hatched chicks for roughly six months.
Looking ahead to 2028 breeding season
Modelling indicated the next breeding season could occur as soon as 2028, Vercoe said. “So, while we'll take a moment to stop and reflect on this remarkable year, we're already looking ahead to 2028 and preparing for what could come next.”
