A hunter who died during the opening of the "roar" was Gordon Douglas Leech, 57, of Katikati.

Detective Senior Sergeant Stephen Ambler said Leech died from a single gunshot wound to the chest while hunting deer in dense and remote bush off Wairakau Rd, about 15km south of Te Aroha on Monday morning.

The shooter was unknown to Leech, Ambler said, but likely to face charges.

"It is a fairly simple inquiry and we will come to that decision quickly, but the appropriate charges haven't been decided, but it's likely that charges will follow."

The Auckland Westpac Rescue Helicopter was sent to the remote spot and a paramedic winched down to work on Leech, however he had suffered an unsurvivable injury.

Ambler said Leech's death was a timely reminder for hunters.

"The cardinal rules around firearms, primarily identifying your target, are key to safety in the bush. It's a fairly dense bit of bush, too. The whole Kaimais are particularly dense and those rules are more important in this bush."

The roar is when stags are at their most vocal, calling to attract the attention of females. They are less cautious during the roar than other times.

Mountain Safety Council chief executive Mike Daisley urged all hunters to follow the Firearms Safety Code.

The "vast majority of firearms-related hunting incidents can be traced back to a firearms safety rule not being followed".

"It's critical to reducing incident numbers that hunters follow these rules," he said.