Penalties for poaching fish during winter spawning season range from a maximum of two years' jail or fines of up to $100,000.
Mr van Dorp believes the 29 trout recovered are only a portion of the true numbers taken recently, with his team and police working to identify several other suspects caught in covert video footage.
Fish & Game officers are hoping more fish will move into the stream to carry on the important wild spawning needed to keep Lake Rotoiti stocks up.
Eastern Fish & Game staff have ramped up their monitoring of local streams and lakes during the spawning season, using both high-visibility patrolling and sophisticated surveillance equipment.
Yesterday's bust saw police officers assisting Eastern Fish & Game staff, with two separate lots of fish located after Fish & Game officers spotted a suspicious vehicle parked off the main road.
"Wild spawning trout are very important to the fishery and need to be protected - it's not just the damage done when poachers take spawning trout but the massive damage they do to the trout spawning grounds and trout eggs in the streams," Mr van Dorp said.
"While we're working hard to limit the damage these poachers can do to our fish stocks, we're also keen to hear from any members of the public who see suspicious behaviour near closed areas or spawning streams."
A toll-free number, 0800-poaching (762-244), can be used to call in sightings.
The two men will appear in the Rotorua District Court on July 31 charged with a variety of offences.