Deep Trolling Options

It’s a cold, wintery day. The water temperature is in the thirties and you’re out in the boat fishing. You look at your sonar and the only fish you mark are suspended at 25 feet.  The only crankbaits you have that go that deep are the wide-wobbling, hot summer baits like the Reef Runner Deep Diver. You suspect that these cold fish will want something presented very slowly with a subtle wobble, but those types of baits just don’t go deep enough.

Or, it’s the middle of summer. The sun is high, the water is clear, and the surface water is warm.  The fish you mark are suspended deep, near the thermocline where it’s cooler. The bait fish are there, too. You’ve tried your deep crankbaits with no luck. Maybe a trolled, worm-harness and spinner combination might be the right presentation for these fish.  But how do you get it down to 25 feet?

There are several ways to get more depth out of your baits. These run the gamut from downriggers to super-thin lines. From in-line weights to in-line divers that pull baits down. Each has its advantages and disadvantages.

The “Troller’s Bible,” Precision Trolling by Holt, Romanack and Irwin contains dive curves for many different lures. These dive curves were created using 10 pound test monofilament line. Line diameter is the dominant variable in running depth for any given lure. Therefore if you want to make a lure run deeper then use thinner diameter line.  Four pound diameter line has been shown to run 25 percent deeper than ten pound line with the same amount of line out.  For example, a Reef Runner Deep Little Ripper runs at 16 feet with 100 feet of ten pound monofilament. That same lure will run 20 feet deep on 100 feet of four pound diameter line (25% of 16=4, 16+4=20).  But trolling four pound line may result in many lost lures and possibly fish.  The answer to the dilemma of strength versus diameter lies in the superlines such as Power Pro or Fireline. Ten pound test Fireline is equivalent in diameter to four pound monofilament. Superlines are the simplest method for getting more depth out of diving crankbaits. But remember there is little stretch in the system. You must use softer rods and lighter drag settings to be able to land fish on superlines.

To go even deeper with deep divers or get shallow diving crankbaits or spinners deep requires a way to pull the baits deeper. In-line weights, snap weights, lead core line, and down-riggers are weighting options for deeper presentations. Depth prediction from added weight to the trolling system is very speed dependent. However, there are some rules of thumb you can apply to each option that will get you close estimates of the running depth. 

In-line weights such as bead chain sinkers or keel weights are available from ¼ oz to 6 oz and beyond. These weights attach to the main line on one end, with a leader to the bait on the other.  A rod length or less leader is desirable in order to be able to land fish. Going longer on the leader may increase bites but it will make it more of a challenge to land a fish when the weight is pulled all the way to the tip of the rod and there’s still lot’s of line to bring in.

Snap weights are the solution when more distance between the weight and the bait is needed.  Snap weights consist of a weight attached with a split ring to a small pinching release (like that on a planer board) that attaches to the line.  To use this system the bait is let out with a desired spacing between it and the weight attachment point.  The snap weight is then clipped to the line and additional line is let out.  When landing a fish with snap weights, the line is reeled in until the weight is close to the rod tip, the weight is unclipped and the fish is reeled the rest of the way to the boat.   

The authors of Precision Trolling have provided a chart for weights of ½ oz to 3 oz and for speeds from 1 to 2 miles per hour. This chart is applicable for spinners and shallow diving crankbaits using 50 feet of line between the

 lure and the weight and an additional 50 feet from the weight to the rod (known as the 50/50 method). Depths up to 30 feet can be achieved with 3 oz of weight with this method.

What about deep divers? Attach a 1 oz snap weight 20 feet ahead of a deep diving crankbait. Use the standard dive curve for that bait and add 33% of depth for the same amount of line out. For example, a Reef Runner Deep Diver will reach 24 feet with 120 feet of line. With the 1 oz snap weight, 20 feet ahead of the Reef Runner, the bait will reach 32 feet (33% of 24 = 8, 8+24=32).

Lead core line is a third weighting option for deep trolling.  Lead core line is woven nylon braid wrapped around a lead center.  The braid changes colors every ten yards to make it easy to keep track of how much line is out.  A leader is attached to the lead core line by a nail knot or a very small barrel swivel.  The lead core is often attached to a backing material by a nail knot before being wound onto the reel.  The depths achieved by lead core line are affected by trolling speed just like with in-line weights.  For example, a shallow diving crankbait on three colors of lead (30 yards) with a 50 foot leader will run at approximately 23 feet at 0.5 mph and 17 feet at 1.0 mph.  Again, deep diving crankbaits will run deeper and it will depend on the bait.  You need to experiment.  At faster speeds it may take up to seven colors of lead to get to 35 feet with a shallow diver.  That’s 70 yards or 210 feet of line to reel in.  Lead core line is large diameter and requires a large reel to hold that much line. 

In order to avoid having to purchase large capacity reels just for this type of presentation, an option that has become popular is to use a three color segment of lead core line attached to standard monofilament on a normal trolling reel.  The lead core segment is attached to the end of the monofilament already on the reel.  You’ll need to have enough space to hold the 3 colors of lead though, so you may have to peel off a few hundred feed of mono first.  The lead core is wound onto the reel and a 50 foot leader is attached.  When presenting the bait, line is let out, the lead is let out and the monofilament attached to the reel is let out.  One hundred feet of ten pound mono let out past the end of the lead segment can reach 35 feet at 0.5 mph and 23 feet at 1.0 mph.

Dipsy Divers and Jet Divers are in-line planers that are used to pull the lures deeper.  They all attach to the main line, with a leader to the bait, like with keel sinkers and bead chain sinker.  They have the same issues with distance from the diver to the bait and leader length that the sinkers have.  But the Jet Diver behaves like a deep diving crankbait.  It is not speed dependent like weights.  Dive curves are available.  A Jet Diver can get to 30 feet on 150 feet of line.  Dipsy’s are a bit more speed dependent since they are weighted but not nearly so as in-line weights.  Dive curves are also available for Dipsy’s.  Large Dipsy’s are able to get to 70 feet with 150 feet of line.  Todd Frank led the Professional Walleye Tour at Bull Shoals in 2005 for two days, pulling big walleyes out of the tree tops in 70 feet of water by using Dipsy Divers.  It was tough for anyone else to get that deep with any other presentation.  But if anyone had had downriggers they could have done it easily.

Downriggers are probably the best, most predictable method for deep trolling.  They are really pretty simple to use.  Downriggers consist of a long arm (like a really heavy duty fishing rod), a cable attached to a weight (downrigger ball), a reel for the cable and a pinch release to attach the fishing line.  The downrigger assembly is bolted to the boat’s gunwale.  To use, let out your bait to the desired length, which will be distance behind the downrigger ball, and attach it to the release.  Put your rod in the rod holder with a loose drag and lower the downrigger ball and cable by cranking the downrigger reel.  There is a line counter on most downriggers that will keep track of how deep the downrigger ball is set.  Tighten the drag on the fishing reel and reel some line in so the rod is bent.  Speed will affect the actual depth that the ball is running but the ball can usually be seen on your boat sonar so adjustments can be made to running depth based on that.  When a fish hits, the line releases from the downrigger and the fish can be fought on the fishing rod and reel.  Keep in mind that downriggers are an investment and take up space in the boat but they are worth it if you troll a lot of deep water.

Regardless of the season, if you can’t find the fish shallow by casting to shore or very deep with live bait presentations, perhaps they are suspended and can be enticed to feed with a slow, deep crankbait presentation like those discussed above.  Give them a try this year.