Before their release, the juvenile whio had been busy building confidence at the hardening facility at Tongariro National Trout Centre.
Whio are river specialists living on fast-flowing rivers.
Hardening facility coordinator Karen Ardin says staff and volunteers noticed the birds acting differently on arrival.
"Two were stand-outs when they arrived as they just didn't want to get in the water. Not wanting to swim is like not knowing how to be a duck!'
Fortunately, the whio picked up a few tricks from their Pukaha cousin and hit the water like pros when released into the wild, she says.
"We released them to the Tongariro River, where we know they have a high chance of survival thanks to the trapping efforts of local community group the Blue Duck Trust."
Whio are a taonga species found nowhere else in the world.
The Tongariro River is a great place for people to spot whio in the wild, even within the township of Tūrangi, Karen Ardin says.
"They're fun to watch, just make sure you give them space to be wild."
