Rule-breakers risk compliance action and having their fishing gear seized.
Otago Fish & Game staff and honorary rangers have been active in the Queenstown Lakes district over summer break. Senior officer Paul van Klink, of Central Otago, said 11 offence notices had been issued by yesterday.
"Some thought they could get away with it.
"Others just couldn’t be bothered," he said.
Six offences had been detected in one day at Lake Hawea.
All of the non-compliant anglers faced action, Mr van Klink said.
"Most of the non-compliant anglers have had licences in past seasons, so they all know the system, which is both disappointing and frustrating for Fish & Game staff," Mr van Klink said.
"If you drive a car, you have a driver licence.
"If you go fishing in freshwater, you have a fishing licence."
He said that considering the price of boats and equipment, and that anglers could spend $50 to $100 on fuel, it was "a no-brainer" to pay $137 for a full-season licence.