Years ago, we noticed bullheads in our pond. We cut, off center, eight inch holes in large trash can lids and wired the lids to the cans. The cans barely floated and, anchored in place, are easily and quietly accessed by boat. Tipping the cans up and slowly dumping the water out traps both the fish and eggs in the can. Lusk's estimate of the number of eggs in the masses is accurate and possibly conservative.