Two Bay of Plenty kiwi chicks were transported from Rainbow Springs in Rotorua to Warrenheip Creche over the weekend.
The pair of North Island brown kiwis will mature in the enclosed forest until they are ready for their forever home in the Otanewainuku Forest near Oropi.
Kopakopa hatched on October 8 last year, and weighed in at 349g. When she left her birth place yesterday, she weighed 1124g. Granite was hatched on October 2 and weighed just 351g. She left there weighing 1098g.
In the wild, kiwi eggs have a 50 per cent chance of successfully hatching. Their survival rate after that is just 5 per cent, which is why eggs are collected from the wild by groups like the Otanewainuku Kiwi Trust to be hatched in captivity.
Kopakopa and Granite will spend about two years in the Warrenheip Creche, which is used by the Kiwi Trust to raise juvenile kiwi to the safer release age of about 2. The site is fully predator-proof.
Kiwi husbandry manager Claire Travers said kiwi chick Granite had to be partially assisted getting out of her egg when she hatched but was fit and healthy when she left Rotorua yesterday.
When the two eggs first arrived they were incubated on site for about a week, then hatched, she said.
Kiwi chicks are usually cared for until they are three to four weeks old, and are then taken to a creche like Warrenheip and left on their own to grow.
Otherwise, like Granite and Kopakopa, they stay at Rainbow Springs in specially created pens and are artificially fed until they are 1kg in weight - a more stoat-proof size.
When kiwis first hatch they have an internalised yolk that they are able to use as a food source in the first seven to 10 days of their lives, before they have to find their own food including insects and worms.
At Rainbow Springs, kiwis start on an artificial diet of ox-heart, mince, vegetables and cat biscuits.
Mr Travers said they could not find enough insects to feed the birds because they could have up to 80 birds on site eating 200g of insects a day.
Mrs Travers said you could not tell the sex of a bird when it was first hatched.
"You have to take feather samples. Male and female chicks look exactly the same, there's nothing definitive about them."
Mature females are bigger than males and have longer bills.
Kiwi populations would not survive if not for the great work done by groups like the Otanewainuku Kiwi Trust, she said.
Volunteers at Otanewainuku Kiwi Trust:
* In or out of the bush, volunteers are the life blood of the trust.