In a land renowned for unusual creatures, New Zealand’s "owl parrot" or kakapo is surely a candidate for the most outrageous. The size of a small dog but with stature of a penguin, this large, rotund bird has an owl shaped head and cat-like whiskers.

Being the heavyweight of the parrot world means the kakapo is flightless, and preferring its own nocturnal company makes it pretty antisocial too. One aspect the kakapo has in common with some of its airborne cousins is extreme longevity, with certain individuals known to live for 120 years.

Befitting a bird that is in it for the long haul they are also notoriously picky breeders, only attempting to reproduce once every three to five years and coinciding with when their favourite food, the fruit of the rimu tree, is in plentiful supply.

We’re thrilled that Richard Henry’s incredibly important genes have been passed on to the next generation

When this painfully slow reproductive rate is coupled with an inability to escape the jaws and claws of a whole host of introduced predators, it is perhaps no surprise that just 25 years ago, the kakapo (Strigops habroptilus) was being earmarked for extinction.

With numbers dipping to fewer than 50 in 1990, the conservation klaxon was sounded and a recovery programme was quickly launched. Since then a small and dedicated team using artificial insemination, artificial incubation, and careful nest management of wild birds has slowly but surely increased their population to 123 adults, all contained within three small, predator-free islands.

Following a bumper rimu fruit crop, conservationists predicted this year to be a record-breaking breeding year for kakapo, but the numbers have exceeded all expectations with 36 chicks surviving the perilous first few months of life and delighting the team. To put this figure into context, only six chicks were raised during 2014, making the "Class of 2016" all the more significant.

Deidre Vercoe, operations manager of Kakapo Recovery explains that she has been waiting 18 years for a breeding season like this.

"In 1990, only one bird survived from mainland New Zealand to join the recovery programme, whilst the other 50 kakapo originated from Stewart Island. This mainland bird, named Richard Henry, was genetically distinct, and bore three offspring in 1998."

After a long and anxious wait, this year Richard’s only daughter produced four chicks of her own.

“We’re thrilled that Richard Henry’s incredibly important genes have been passed on to the next generation," Deidre adds.

Now is the time to keep up the momentum with recovery efforts

The coming weeks will be crucial, since the young kakapo are still not out of the woods. Back in March, for example, a flash flood killed three individuals. As each egg hatches, Deirdre’s team regularly check and weigh the chicks until the point they fledge at around 10 weeks. Each chick is so crucial to the survival of its species, that if it is found to be struggling in the wild, it will be swiftly brought in for hand rearing.

And although they are now four months old, their delicate nature means the chicks won’t be added to the total kakapo head count until October. DNA analysis is also being undertaking to confirm sex and parentage of all the chicks, which will allow the team to constantly assess the genetic diversity of the population, in addition to gauging whether artificial insemination was successful.

Given the birds' rarity status and charismatic nature all the adults are named. Sirocco, a hand-raised kakapo, even possesses his own Facebook page.

"Now is the time to keep up the momentum with recovery efforts to ensure the Kakapo continues to strengthen," adds Maggie Barry, New Zealand’s Minister for Conservation.

UK viewers can watch the final programme from the series New Zealand: Earth's Mythical Islands on Tuesday 2 August at 20:00 BST.

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