"The final didn't pan out the way I thought it would," said Butler.
"I got a bit of a slow start, I wanted to catch the first wave of the final and get under way quickly.
"I am stoked to win because my goal is to win the New Zealand grommet series for both the under-16 and under-14 divisions and this result helps a lot," he said, with his sights set on the overall series which wraps up on the Waikato's west coast at Raglan in two weeks.
In the girls' under-14 final at Fitzroy Beach, the four finalists were from Mount Maunganui.
Kea Smith won with a score of 10.17, with Raiha Ensor second (9.0), Elin Tawharu third (7.77) and Maaia Reid-Bennett fourth (5.4).
It was Reid-Bennett's fourth consecutive final but that winning score still eludes her.
Smith followed up that victory with a strong showing in the girls' under-16 final, where she was just beaten into second place by Claudia Fraser from Auckland.
Iritana Butler rounded off a great day for Mount Maunganui surfing by claiming silver in the girls' under-12 final.
The surf conditions at Fitzroy Beach were described by Surfing New Zealand's Ben Kennings as "tricky, small waves that stayed around 0.5m all day with light onshore northwest winds", which suited the Mount Maunganui surfers, who are used to those conditions.
The Hareb Deken MotorGroms is a new event on the world-class New Zealand grommet series and was part of the TSB Bank New Zealand Surf Festival which began on Good Friday and continues through to April 7.