The Department of Primary Industries and Regional Development has launched a new surveillance program to monitor remote fishing activity and protect fish stocks.
Operation Shadowedge started with surveillance activities in Collie, targeting commercial and recreational fishers by using drones and long range cameras.
Department compliance manager Brad Tilley said fishers should prepare to have their catch checked at any place, at any time, after recent surveillance identified evidence of marron fishing out of season.
"I encourage all fishers to keep up-to-date with the current rules to make sure they are fishing within the rules," Mr Tilley said.
"The focus is on surveillance activities and encouraging voluntary compliance through various education campaigns.
"In Collie, fisheries officers targeted dams fished for marron and partnered with other government agencies to cover a large area over the two-day operation."
If you witness fishing activity that doesn't look quite right, contact FishWatch on 1800 815 507.