"Enforcement of the regulations and laws is required to provide a motivation for people to comply with the rules," van Dorp said.
"Our trout fisheries are funded solely by income from licence sales.
"Other regulations are set to ensure sustainability of the fisheries into the future and that the fisheries are managed and maintained for the enjoyment of all who wish to fish legally."
Van Dorp said the figures were in line with previous years but within the past month there had been an increase.
"We have had an increase in offending in the Rotorua area, with five people dealt with for fishing without a licence or fishing in closed waters," he said.
"We've had 10 youths dealt with for poaching or attempting to poach trout in spawning streams."
He said fishing in spawning streams had unseen consequences.
"If walking in a spawning stream they are tramping on eggs ... It's hundreds or thousands of potential fish."
The most common offence in the 2017/18 season was fishing without a licence. It made up 24 of the 73 offences.
That was followed by fishing in closed waters which had 10 recorded offences. There were seven offences of having an unpinned shotgun and six of using a lead shot and for using illegal tackle.
Fewer than five offences were recorded for disturbing spawning gravels, being unlawfully on property, fishing during closed hours, giving false details, fishing with or possessing illegal tackle, fishing with more than one rod, obstruction of rangers, possession of a net/spear/implement, taking spawning fish with a net/spear/implement and exceeding the fish limit.
Van Dorp said illegal tackle offences were down last season. It was usually one of the most common offences.
Breaching Fish & Game regulations carry a broad range of punishments.
The maximum penalty for fishing without a licence or using illegal method or fishing in closed waters is $5000 or community work.
Offences involving poaching spawning trout or obstructing a ranger are punishable by up to two years' imprisonment or a $100,000 fine.
"We continue to have rangers checking streams and lakes around the region. People tempted to fish illegally need to be aware that the penalties can be significant," van Dorp said.
The Eastern Region covers centres like Rotorua, Taupō, Tauranga and Gisborne, and van Dorp said officers checked up to 3500 people for fishing and hunting licences each year and only a handful were found to be breaching regulations.
"It's not worth taking the risk and when people are caught, unless it's a genuine error, we hold those people accountable.
"We do take it seriously we've got a lot at stake in our region."
Most common offences
- Fishing without a licence: 24 offences
- Fishing closed waters: 10 offences
- Unpinned shotgun: 7 offences
- Lead shot: 6 offences
- Illegal tackle: 6 offences