The heaviest fish for the day, a 3-year old hatchery release from Lake Rotoiti, tipped the scales at 4.1kg.
Fish & Game rangers were at most of the boat ramps carrying out surveys and compliance checks.
"We talked with hundreds of anglers, but the weather did keep some people away in the end," Osborne said. All of the anglers Fish & Game spoke with were fully compliant.
Sunday's weather was much improved, and anglers made the most of it.
Osborne said while the opening day celebrations were a big event for Rotorua, some of the best trout fishing lay ahead over the summer period.
"Warmer spring conditions will bring fish on to the feed and the lakes fish really well in spring and summer when smelt are on the move," Osborne said.