Stratford, who works for Peter Lyon Shearing, added to his many titles which included one win at the event before.
He did not finish first, so assumed he had made up the points on quality.
His win was met by a haka from children in the audience.
After a tiring few days he "just wanted to hang out with the family".
Karauria said the feeling of winning again was "amazing".
"There was heaps of support from the audience. I had some really tough competition."
On Saturday night she said she was "too full of adrenaline" to feel tired.
She was also fifth in the senior shearing, once again achieving the rare feat of entering both events.
She works for her father, shearing contractor Dion Morrell.
"There are three shearers that have really helped me out this week by shearing for me, so I'll shout them a few tonight."
The event attracted a combined 150 entrants for the individual shearing and woolhandling events.
Co-organiser Graeme Bell said it was great to have the title back in New Zealand hands.
"Aussies set the benchmark tonight and the New Zealanders lifted their game. The group of Australians here are all very good merino shearers."
The senior shearing was won by Jack Glover, of Tasmania, the senior woolhandling by Emily Turipa of Gore and the junior woolhandling was claimed by Autumn Waihape, also of Gore.