Rangers from Kurow, Omarama and Twizel, along with officers from Temuka, have been keeping a close watch on anglers for about a month, and about half a dozen prosecutions are pending for breaches of fishing regulations.
The charges include taking more salmon than an angler is entitled to.
Anglers can fish in Lake Benmore and the canals year-round and recent salmon releases at both locations - of more than 18,000 fish up to weighing 2kg each - had attracted an unseasonal number of anglers, Kurow-based fish and game officer Graeme Hughes said yesterday.
But during "these times of plenty" there had been "times of greed" and Temuka fish and game officer Mark Webb said yesterday that had prompted increased ranging of the areas.
"Ranging trips have been quite extensive for such a small area over the past month, and will continue," he warned.
Mr Hughes said released salmon from salmon farms had the same status as wild salmon, with a daily limit of two.
"Sadly, there are people who think they deserve more than two a day and Fish and Game has had to deploy law enforcement operations to dissuade the pot hunters," he said.
Offenders liked to think they were smarter than enforcement officers and were trying to get around the law.
"For example, they resort to making more than one trip a day to their favourite fishing spot, taking away a limit bag, returning some time later for their second and even third for the day.
"Using the same vehicle each trip is not fooling anyone and now that law-abiding anglers are aware of it, the perpetrators have resorted to using different motor vehicles on their second or third visit," Mr Hughes said.
Despite their efforts, bona fide anglers were not being fooled and information was soon in the hands of enforcement officers.
Since the release of the salmon in Upper Waitaki waters, infringement notices had been issued for fishing for sports fish without a current fishing licence, failing to produce a current licence on demand and exceeding the daily bag limit of salmon.
The pressure increased by the release last week of 2000 large salmon at Ohau C donated by Richard and Margaret Logan, owners of High Country Salmon. The 2-year-old fish averaged 2kg.
"Releases of large salmon in such numbers are a first for the region - in fact, a first for New Zealand - and will certainly be appreciated by the many anglers who fish the Lake Benmore," Mr Hughes said.
A percentage of the released salmon had been tagged and anglers were asked to record the numbers on the yellow tags, along with when and where they were caught, and send the information to Fish and Game.
