Most offshore trolling happens at the surface, but some of the best fish feed deeper. Wahoo, kingfish, and tuna often hold below the surface when the sun is high or the water is warm. Downriggers and planers both solve that problem, but they work differently and fit different boats.
How a downrigger works
A downrigger is a small boom with a cable and a heavy weight, often called a cannonball. A release clip on the weight holds your fishing line. You lower the weight to a precise depth using a counter, and your lure trails behind it. When a fish strikes, the line pops free and you fight it directly on the rod.
Strengths: exact depth control, easy to repeat a productive depth, and a direct fight once the line releases.
Limits: most downriggers work best at slower trolling speeds. At high speed the cable blows back and depth becomes unreliable. They also take up gunwale space and cost more.
How a planer works
A planer is a diving device tied into the line ahead of the leader. Water pressure drives it down, pulling the lure with it. On a strike, many planers trip and stop diving so you can bring the fish up. Planers are often run on a heavy dedicated rod or a hand line with a shock cord.
Strengths: inexpensive, simple, and they work at higher speeds, which makes them popular for wahoo.
Limits: depth is less precise and changes with speed and line length, and the planer adds weight to the fight.
Which one to choose
- Kingfish and slow trolling: downriggers shine, especially with live bait or spoons at 2 to 5 knots.
- Wahoo at high speed: planers or trolling weights are the usual choice because they hold at speed.
- Tuna under birds or on marks: either can work; downriggers give precise depth if fish are holding at a set level.
- Smaller boats: planers take no extra hardware and are easy to add to an existing spread.
Running deep lines with a surface spread
Deep lines usually run from the corners, straight back and down, so they sit below the surface lures without crossing them. Keep them shorter than the surface flat lines and watch for tangles in turns.
Tips
- Use a fish finder to see what depth fish and bait are holding at, then match it.
- Mark the line or note counter readings when you get bit.
- Use wire leaders behind planers when wahoo are around.
For a deep dive on planers specifically, read our guide to trolling with a planer, and see wahoo trolling weights for another way to get lures deep.
