Slow trolling is a little known but highly effective technique for catching large bluefin tuna. This technique involves slowly trolling rigged ballyhoo or other baits along the bottom where large bluefin tuna are congregated to feed on concentrations of bait.
Borrowing methods from local striped bass fishing, anglers use a variety of rigs which put the bait near the bottom. As in some other trolling practices, a 20′-50′ leader is employed, connected to the main line with a small swivel capable of passing thru the rod guides and onto the reel.
A 28 to 32 oz. sinker is attached to the line by wrapping a rubber band around the line or by attaching the sinker to the swivel via rigging wire or floss.
While the boat maneuvers as slow as possible, the rig is slowly lowered until it bumps the bottom. As the boat continues to troll slowly, more line is payed out until the rig is oriented just off the ocean floor.
This method works when the fish are holding tight on structure perhaps feeding on small red hake or squid. The technique is similar to boats that choose to drift a bait deep while chunking over the same areas.