In the Tararua District, a 55-year-old man was shot in the eye with a shotgun pellet.
A rescue helicopter was sent from Palmerston North to Akitio to collect the man shortly after 8am.
A helicopter spokesman said the man had been taken to Palmerston North Hospital in a stable condition.
About 15 minutes earlier in Lismore, near Ashburton, a man in his 30s was shot in the wrist in a duck hunting incident.
He was flown to Christchurch Hospital.
Mr Coleman said there had been numerous complaints relating to duck hunting this morning.
These included shotgun pellets reportedly hitting the roof and windows of a Waipara house, and shots being fired near a property in Whitford in southeast Auckland.
Northern police communications said they had several similar calls, including from a woman who was concerned about gunshots near her house in Parakai, north of Auckland.
Meanwhile, a post was added to the Russell Noticeboard Facebook page showing two Caspian Terns thought to have been shot by duck hunters.
"How dare people shoot them out of the sky & leave them floating in the water. Very sad," Mandy Cleland said.
Mountain Safety Council chief executive Mike Daisley said it was "unfortunate but not uncommon" to have so many incidents at the start of the duck hunting season.
"The kick off to the duck shooting season often brings a real a festive season, a bit of a celebration, almost a bit of a boys' weekend feel to it and that combined with a lot of individuals in very cramped spaces - maimais don't have a lot of room in them - accidents can happen."
Almost all incidents were related to people breaking one or more of the Firearms Safety Code, with duck hunting incidents generally the result of people not checking their shooting zones or poor muzzle control.
Drinking was also a tradition at the start of the duck hunting season, he said.
"We're encouraging people to have celebration drinks after they've finished their duck hunting," he said.
Last season a teenage boy was killed in the North Island. His death was the fourth duck hunting fatality since 1992.
Senior Sergeant Steve Crawford said these incidents were a timely reminder for all hunters to remind themselves of the seven basic rules of firearms safety.
"On occasions when hunters momentarily drop their guard, the consequences can be absolutely tragic."
The Firearms Safety Code:
1. Treat every firearm as loaded
Check every firearm yourself.
Pass or accept only an open or unloaded firearm.
2. Always point firearms in a safe direction
Loaded or unloaded, always point the muzzle in a safe direction.
3. Load a firearm only when ready to fire
Load the magazine only when you reach your shooting area.
Load the chamber only when ready to shoot.
Completely unload before leaving the shooting area.
4. Identify your target beyond all doubt
Movement, colour, sound and shape can all deceive you.
Assume colour, shape, sound, and shape to be human until proven otherwise.
5. Check your firing zone
THINK: What may happen if you miss your target?
What might you hit between you and the target or beyond?
Do not fire when you know others are in your firing zone.
6. Store firearms and ammunition safely
When not in use, lock away the bolt, firearm and ammunition separately.
Never leave firearms in a vehicle that is unattended.
7. Avoid alcohol or drugs when handling firearms
Good judgement is the key to safe use of firearms.