Ghost Gear Project

I am putting in a proposal to locate and retrieve lost "ghost" fishing gear for DFO (government of Canada) previous programs have failed due to the fuel consumption being out of control. I am looking into the feasibility into using drones or submersibles, fitted with infrared sounding, to locate the gear. Thank you for any and all help you can provide. The budget is there to use the newest and best tech I just need expertise.