Bumper breeding season for kākāpō on the cards

University of Auckland Professor Jacqueline Beggs, who chairs the Kākāpō Recovery Group, says the team is currently hoping for chicks from all 84 breeding-age females.

This would significantly boost the population of the critically endangered, flightless native parrot, which currently sits at 237 birds.

“When the kākāpō recovery programme began in 1995, they were on the brink of extinction with only 51 birds, and just 20 of those were female.  

“Now, the stars are aligning for the best breeding season since records began in 1977,” says Beggs, who is co-director of the University’s Centre for Climate, Biodiversity and Society, Ngā Ara Whetū.

The prediction that plenty of eggs will be laid this summer is based on the amount of fruit on rimu trees and all the female parrots being in good breeding condition – a rare event.

The last big breeding season was in 2022, when 57 chicks fledged.

Waipapa Taumata Rau, University of Auckland contributes key research on kākāpō, supporting planning for the long-term recovery of the species.

Professor Mike Taylor’s lab produced the first detailed description of kākāpō gut microbiota, helping conservationists understand how diet, antibiotics, and environmental stressors influence their health.

Dr Caroline Lees has developed tools to help predict how different breeding and site-management scenarios would affect kākāpō population growth and extinction risk. These models are helping assess shifts in rimu fruiting due to climate change, and supporting the Department of Conservation’s planning for translocating the parrots to new sites.

Scientists don’t yet understand how, but kākāpō sense when rimu trees are about to fruit heavily and that signal triggers the start of a bumper breeding season, says Beggs.

“This year’s counts showed the amount of fruit setting on rimu branches is extraordinarily high.

“They need the fruit available for when their chicks hatch,” says Beggs.

If the parrots have detected the rimu fruit cue, the males will kick off an elaborate mating ritual this month.

Kākāpō are the only lek breeders among New Zealand’s native birds and the only known lek breeding parrots in the world. Lek breeding means the males put on displays for females, who choose one or more mates, then raise the chicks alone.

“The males congregate up high and send out booming calls that attract the females, who decide who does the best booming and who they want to do the deed with,” says Beggs.

Mating usually begins around Christmas and peaks in January, with eggs laid in February and March taking about a month to hatch.

By September or October 2026, the chicks sparked by this year’s rimu fruiting will reach independence and be officially added to the parrot’s population.

“It’s a long haul and lots can go wrong.

“Some years, the rimu fruit fails to ripen due to rogue weather or other factors and the kākāpō will then abandon their nests.”

While it’s great news that kākāpō numbers are likely to increase dramatically, finding new areas the population can expand into poses a challenge, says Beggs.

At present, the nocturnal parrots are in four predator-free sanctuaries, three of which are on offshore islands.

However, the island havens are reaching capacity, so now some of the ground-dwelling parrots will be relocated to areas where predators have been reduced, but not eliminated.

“We’re moving from a species in intensive care toward a future where kākāpō can establish natural populations in different areas. That’s scary and exciting.

“It’s something we could barely imagine when the kākāpō recovery programme began in the 1990s,” says Beggs.

Once kākāpō reach high numbers in small, predator-free areas, the risk of fighting between males and nest interference increases.

“We also don’t want all our eggs in one basket – we need to start spreading the population, so if disease gets into one island, it doesn’t wipe out the whole population.”

That’s particularly important, because the genetic bottleneck around 1995, when only 51 birds remained, has probably weakened their immunity.

Kākāpō might live for as long as 90 years and fossil records show they once lived throughout mainland New Zealand, says Beggs.

“There’s a presence about them that commands respect.

“Each one has its own personality and they’re so internationally unique – everything you think a parrot is going to do, kākāpō do differently,” she says.

With enough control of predators, such as stoats, feral cats and rats, hopes are high that these “cool birds” won’t become extinct after all.

“It’s one of the few critically endangered species in the world that has had its trajectory turned around.

“This is why I do this work – it’s a story of hope,” says Beggs.