Downrigger Fishing: Setup, Depth Control, and Mistakes

A downrigger turns a floating lure into a precision tool. It clips your line to a weighted cable, holds the lure at an exact depth, and lets go the instant a fish strikes. If trolling is new to you, start with the basics of trolling speed, depth, and lure choice before adding a downrigger to your setup. The gear shows up on lake boats and on saltwater salmon trolling runs alike, because depth control matters everywhere fish suspend below the surface.

What a Downrigger Actually Does

A downrigger lowers a heavy weight, often called a cannonball, on a steel cable spooled from a mounted reel. Your fishing line clips to a release near the weight through a separate spring-loaded clip. When a fish hits the lure, the line pops free of the clip and you fight the fish on a slack line, not against the weight.

Most boats mount downriggers on the transom or along the gunwale near the stern. The boom needs enough length to clear the motor, trim tabs, or swim platform. That clearance also keeps the cable away from the propeller during hard turns or rough water. Anglers running four units typically put a unit in each transom corner and flank the motor with the other two, angled outward for a wide horizontal spread.

Rigging Up: Weights, Cable, and Release Clips

Downrigger weights commonly run 8 to 15 pounds for lake fishing, with heavier balls used in strong current or deep water to reduce drag and cable angle. Attach the fishing line to the release clip, then walk the lure out behind the boat to your target setback distance before lowering the weight.

Once the weight is down, drop the rod into a holder beside the downrigger. Reel in the slack, then pull the line tight against the clip without popping it loose. A properly set rod tip should bend into a visible arc. Set your reel’s clicker so a strike sounds off even if nobody is watching the rod.

Some anglers add a small temperature or speed probe just above the weight to track conditions at depth. These sensors add drag and worsen cable angle, so pair them with a slightly heavier weight to keep your depth readings accurate.

Setting Your Depth Precisely

Your line counter tells you how much cable is out, not necessarily how deep your weight sits. Forward motion and current push the cable backward, an effect called swayback. The faster you troll, or the stronger the current, the more pronounced it becomes.

Say you want a weight sitting at 80 feet. Swayback might leave it at 70 feet even though the counter reads 80. Compensate by letting out extra cable beyond your intended depth, then verify the real depth on your sonar screen. This is also why locating fish before you set your gear matters so much. Sonar shows the thermocline, baitfish schools, and bottom contour, so you’re not guessing at a depth and hoping.

Diving plugs add another wrinkle. A plug that dives 5 to 6 feet on its own, set at your normal distance behind the weight, needs the weight raised to roughly 13 to 14 feet on the counter if you want the lure itself running at 20 feet. Account for the lure’s own dive depth on top of the weight’s true depth.

Downriggers shine for depth-sensitive species. Kokanee often hold in a narrow temperature band, and a downrigger lets you park a lure in that exact zone and hold it there trolling pass after trolling pass.

Speed and Lure Action Behind the Ball

Setback, the distance between the weight and your lure, can be as short as a rod length or stretch past 200 feet. As a rule, fish deep water with a shorter setback and fish shallow water with a longer one. Shallow weights sit close to the surface where boat noise and shadow can spook fish, so extra distance helps.

You can measure setback a few ways. Reels with built-in line counters give the most accurate reading. Without one, count the passes a levelwind guide makes across the reel, then multiply by the line length per pass. Or strip line off by hand in measured pulls, one or two feet at a time, and count the pulls.

Boat movement changes lure action even when your gear stays put. Steer in gentle S-turns or vary your speed to make lures flutter and dart, which often triggers a strike from a following fish. On turns, outside lines speed up while inside lines slow down, so expect some tangling risk with multiple rods out.

Fighting a Fish off a Downrigger

When a fish hits, the release clip lets the line go free before you touch anything. The rod tip drops, then springs back and starts bouncing, and the clicker sounds if the fish pulls line. Grab the rod and reel down until you feel the fish.

What happens to your other lines depends on how many you’re running. Charter captains fishing five or six rods often slow down but keep moving, working the boat to avoid crossing lines rather than pulling in the whole spread. Anglers running one or two lines can usually just reel everything in without much trouble.

For a big fish, clear every line, shift the boat to neutral, and maneuver with the motor as needed to keep the fish positioned. Fighting a fish from a stationary boat gives you far more control than trying to do it while still trolling.

Mistakes That Cost You Fish

• Trusting the counter blindly. Ignoring swayback means your lure runs shallower than you think, often right over the fish instead of through them.
• Skipping sonar. Setting a depth by feel instead of by marking fish or the thermocline wastes trolling time and risks snagging bottom.
• Guessing at setback. An inconsistent setback makes it hard to repeat a pattern that’s working, so use a line counter or count your pulls every time.
• Stacking lines too close together. Less than 10 feet of separation between stacked lures invites tangles the moment a fish strikes and runs.
• Running the boat off a straight line while setting gear. Turning while you deploy lines crosses cables and tangles rigs before you even start trolling.

Frequently Asked Questions

How deep should I set my downrigger? Check your sonar first. Look for baitfish, marked fish, or a thermocline break, then set your weight a few feet above that band, since most gamefish strike upward. Depths run from just under the surface to well over 100 feet. Adjust as sonar readings change through the day.

What is swayback and how do I compensate for it? Swayback happens when boat speed or current pushes your cable and weight backward, so your counter reads deeper than the weight actually sits. Faster trolling and stronger current make it worse. Compensate by letting out extra cable beyond your target depth, then confirm the true depth on sonar.

How far back should my lure trail behind the downrigger weight? Setback can run anywhere from several feet out to a couple hundred, depending on depth and species. Fish deep water with a short setback, since less line between weight and lure is usually enough. Fish shallow water with a longer setback so the boat and cable don’t spook fish near the surface.

Can I fish two lines off one downrigger? Yes, this is called stacking. Set your first lure and lower the weight 10 feet, then clip a second release onto the cable above it and set a shorter lure behind that one. Keep at least 10 feet between the two lines to prevent tangles when a fish strikes.