The duck-hunting season began at dawn on Saturday and quickly notched up its first human injury.
The police said a 44-year-old man has been flown to Wellington Hospital after being shot in the elbow.
The man was shooting at Bideford north of Masterton when the incident occured at half past eleven on opening morning.
The police initially said it was unclear whether the lead shot richocheted off another object or if he was shot at close range.
A Fish & Game executive said the organisation - which sells hunting licences and advocates for shooters - was disappointed there had been an accidental shooting on the first day of the season.
Otago chief executive Niall Watson said it was an unfortunate way to start the season.
"It's never good to have a firearms accident, and hunters do need to take particular care when handling firearms," he said. "It's disappointing to have an accident."