Welcome to the world of Precision Trolling, the ultimate example of depth control fishing. Originally published in 1991, this book is dedicated to every angler who has picked out a favorite lure, attached it to his line, let the bait out behind the boat and trolled his or her way to fishing success.
Fundamentally, trolling is the most efficient of all fishing methods. This bold statement is indisputable because trolling allows anglers to cover copious amounts of water, fish multiple lures and live baits, vary depths on these lures while at the same time experimenting with various lure colors, boat speed and even line types. No other form of fishing even comes close to triggering as many strikes as trolling. The reason is overwhelmingly simple: trolling keeps lures and baits in the strike zone longer and more efficiently than any other means of fishing. Period.
Besides being efficient, trolling is also effective at catching nearly anything with fins. Certainly the most popular species targeted by trollers include walleye, trout, salmon, pike and musky, but trolling tactics are equally adapted to catching striper, large and smallmouth bass, catfish, a host of saltwater species and even popular panfish like crappie, bluegill and perch. In short, the species of fresh and saltwater fish that are routinely caught trolling is longer than the line at the Tasty Freeze on that first warm day of spring.
The landmark research conducted by the staff of Precision Trolling started in the early 1990’s not from a desire to sell fishing books, but rather from the need to better understand the dynamics that influence trolling success. It wasn’t until months after we generated our first proprietary XY depth charts of popular crankbaits that it became obvious other fishermen would want to benefit from this knowledge. Imagine knowing exactly how deep your favorite lures will dive based on the simple to understand and easy to duplicate principle of manipulating lead length and line diameter!
The Precision Trolling “Dive Curve” was born, the book Crankbaits In-Depth published and the rest is history. For the first time anglers could tap into research that provides rock solid data on the diving depths of popular crankbaits. Armed with this knowledge countless anglers have used the Precision Trolling Dive Curves to target a wealth of species, while at the same time eliminating the frustration of snagged lures.
Soon after introducing Crankbaits In-Depth the staff of Precision Trolling expanded their research to include other popular trolling hardware. The book was renamed Precision Trolling and eventually other publications including Precision Trolling Big Water and Precision Casting were released.
It didn’t take the Precision Trolling staff long to come to the conclusion that confirming lure diving data was going to require countless hours of actual underwater observation using modern scuba diving techniques. The testing standards used by the Precision Trolling staff are based in hard science and the need to create data that’s easily duplicated by other anglers. To accomplish this a set of base line standards had to be established.
Because the Precision Trolling staff was primarily interested in walleye fishing, their original books were based on 10# test monofilament line which was the logical choice for walleye trolling applications. As more trolling hardware was tested, the staff expanded these base line standards to include super braid lines and other line diameters suitable for these trolling applications.
Today the typical Dive Curve produced by Precision Trolling shows a lure or device tested on at least two different line types, diameters or trolling speeds. Tens of thousands of anglers in the United States, Canada, Europe and other parts of the world depend on the data created by Precision Trolling to help them better target their favorite sport fish species. What makes Precision Trolling so popular is the mutual understanding that getting the most from crankbaits and other trolling gear requires the intimate knowledge of exactly how deep these devices dive. No matter what species is being targeted, if an angler has no clue how deep lures are diving, consistently catching fish is going to be a fleeting experience!
A number of factors influence on the diving depth of crankbaits and other trolling gear. This list includes but is not limited to lure size and weight, lip size, lip angle, lead length, line diameter, line type and even the orientation or “attack angle” of the lure as it runs in the water. Thankfully the staff at Precision Trolling has already done the hard work and tested literally hundreds of popular lures and diving devices using mutually accepted line types and diameters.
After nearly two decades of research, we continue to use scuba diving methods to document the diving data published in our books. This method of documenting trolling information is expensive, time consuming and pretty boring stuff, but the data created is irrefutable and also invaluable to anyone who trolls.
In short, our hard work has taken the mystery out of depth control fishing and provided anglers with easy to interpret XY graphs that enable them to literally aim their favorite lures or diving devices at fish by monitoring and manipulating simple variables like lead length and line diameter.
By simply monitoring the “line out” or “feet back” measurements on the Dive Curve horizontal axis, it’s easy to determine how deep any lure is diving below the surface as indicated on the vertical axis.
The Precision Trolling “Dive Curves” are easy to use, highly accurate and they allow anglers to predict the running depths of their favorite lures at literally all common lead lengths and line diameters. The methods used to document the diving depth of lures and trolling hardware published in the Precision Trolling books is consistent and will remain that way. However, the ways this information is provided to the consumer is constantly changing.
The advent of the digital age has allowed the staff at Precision Trolling to part ways with the bulky, expensive and hard to navigate printed books we have produced for years in favor of offering electronic forms of data. Ways anglers will be able to access the Precision Trolling Dive Curves include affordable phone applications for both Apple and Android style smart phones and SD memory cards designed to function in sonar units. The proprietary Precision Trolling Dive Curves can also be printed on vinyl stickers sized to fit popular 3700 series lure storage boxes.
Even better, updates will be available electronically almost as quickly as new lures are introduced and tested. Gone are the days of buying a whole new book just to access some key data. Gone also are the lengthy delays in getting new data into angler’s hands. Technology is a wonderful thing that can and is making the lives of fishermen easier and the time they spend on the water more productive.
TROLLING IS BORING?
To many anglers the process of trolling seems redundant, mundane or even downright boring. To those who don’t immediately recognize the value of trolling I reply that trolling in its most sophisticated form is designed to be redundant. The whole process of determining the precise combination of lure type, lure action, lure depth and lure color that effectively triggers a strike, then duplicating what worked, is exactly what trolling is all about.
Ardent trollers refer to this as “reproducibility” or the ability to identify a set of fishing variables that lead to success and then duplicating them exactly so as to repeat the fish catching success. Later in this text we’ll identify all the variables that influence trolling in detail, but for now lets stick with the philosophical rather than analytical approach.
HOW DEEP IS THAT LURE RUNNING?
For every angler who has trolled a lure behind the boat, there has been an angler who wondered how deep that lure was fishing. Finding answers to this fundamental question is the whole reason the staff of Precision Trolling has spent decades studying the art of trolling, exposing the benefits of depth control fishing and publishing their finding to countless anglers. The ability to predict lure running depth with certainty and then to duplicate that knowledge is the holy grail of fishing. In short, knowing how deep a particular lure is diving enables the angler to effectively “aim” his or her lures at fish that have been located with the help of sonar.
IDENTIFYING THE KEY VARIABLES
The art of trolling involves a number of variables that if understood and carefully controlled enable the fisherman to accurately predict the running depth of popular fishing products including crankbaits, spoons, spinners, diving planers, snap weights, keel sinkers and sinking lines like lead core or soft copper wire. The most important variables include lead length or the amount of line deployed behind the boat, line diameter and trolling speed. Let’s take a more detailed look at each of these important trolling variables.
Trolling lead length is the most important variable that controls lure running depth. In general, the longer the lead length, the deeper a lure or bait is likely to run. However, it’s important to note that a point of diminishing return eventually occurs, forcing the angler to work within what amounts to “reasonable” lead lengths. In years past it was a popular theory that deploying too much line out would actually cause certain lures like crankbaits to loose running depth due to the added line drag or friction in the water. Actually, the Precision Trolling staff proved this theory false before publishing any of their now famous depth data charts.
What actually happens is crankbaits and most other lure types continue to gain additional depth as more line is deployed. At some point, the amount of increased depth achieved becomes disproportionate to the amount of line that must be played out. In other words, gaining just a few inches of lure depth, may require letting out hundreds of feet of additional line which is counter productive on a number of levels.
Certain line types favor the process of gaining additional lure depth. Monofilament and co-polymer fishing lines are hands down the most popular with trollers. The properties of these lines makes them a good “compromise” for the angler who’s trying to achieve significant lure diving depth without sacrificing features like line diameter, value, abrasion resistance, controlled stretch, etc.
Monofilament and co-polymer lines continue to be popular, but low stretch super braids are becoming more and more popular with anglers who are demanding maximum depth from their lures and maximum life from their fishing lines.
Low stretch and super thin diameter are the overwhelming advantages of fishing with super braids. Among these lines two distinctive categories exist including fused lines made from Microdyneema fibers and twisted or braided lines made from Spectra fibers. Both line types are similar in cost and function, but are marketed as vastly different products. In practice, most anglers could not tell the differences of super lines made from Microdyneema or Spectra fibers.
Super thin, low stretch super braids enable lures and other trolling devices to achieve substantially deeper depths. The reason for this is the thinner diameter lines create less friction when passing through the water, in turn allowing lures and trolling hardware to achieve greater depths.
By comparison monofilament and co-polymer lines are larger in diameter for the same break strengths and these lines are exceptionally buoyant as well. The fact that monofilament and co-polymer fishing lines float is another little known but fundamental piece of knowledge.
When using buoyant lines including monofilament and co-polymer nylon lines the vast majority of the line deployed behind the boat is floating at the surface. Most anglers envision that when trolling their fishing line is progressively angling down into the water towards the lure they are fishing. In part this is true, but what more specifically is happening is responsible for one of the inherent disadvantages of trolling.
Say 100 feet of line is deployed behind the boat. As much as 80% of that total lead length is actually floating at or very near the surface. Only the last few feet dives into the water at a significant angle. This phenomena occurs because most popular fishing lines float and the forward motion of the boat pushes against the line creating a defined bow.
The underwater studies of Precision Trolling are conducted using high visibility line colors that make it brutally obvious how defined the “bow” in the line can be. The deeper a lure dives, the more pronounced the “bow” in the line becomes.
When a fish strikes a trolled lure, this inherent bow in the line must be pulled taunt before the fish is hooked. Depending on trolling speed and how deep the lure is diving, it can take several seconds for the line to pull taunt. This in turn provides fish ample opportunity to reject a bait after striking, but before being hooked.
This is precisely why trollers routinely notice strikes that don’t materialize into hooked or landed fish. The best way to combat this problem is to fish with lures that have “sticky” sharp hooks that make it more difficult for a fish that strikes to shake the lure before the line pulls tight.
Super braid lines experience the same “bow” in the line, but the amount of bow is somewhat less than super buoyant lines like monofilament. Using super braid lines is another option that helps to hook more of the fish that bite.
Employing faster trolling speeds also increases the likelihood of solid hook ups. While anglers can do a few things to manage the amount of bow in the line while trolling, they can not eliminate this problem completely. Ultimately the mood of the fish is just as important as the line type, line diameter and trolling speed used. Active fish tend to strike at lures viciously and become helplessly hooked in the process. Fish that are somewhat inactive may strike but with less enthusiasm and often are not hooked as solidly as fish that are feeding actively.
Keeping a tight line on fish that are hooked is always important, but setting the hook is rarely a good idea when trolling. The vast majority of fish that are hooked while trolling can be landed successfully so long as the angler keeps steady pressure on the fish. The more the fish struggles, the deeper the hooks tend to penetrate.
Setting the hook can and does in fact dislodge the hooks by literally tearing them from the tissue inside the fish’s mouth. This is especially noticeable when fishing with super braid lines that have little or no stretch.
The best advice is to come tight against the fish as quickly as possible when a strike is detected, then slow up the retrieve to a uniform speed that keeps steady and solid pressure on the fish. Let the power of the rod and friction of the line passing through the water tire the fish.
The Precision Trolling staff is often asked, “what about fluorocarbon lines” when talk turns to the properties of fishing line. Fluorocarbon lines are carbon based and were designed to have less stretch than monofilaments, lower visibility in the water and more abrasion resistance. All of these are properties that make a good “trolling” line. Fluorocarbon line also has a density slightly greater than water which means is sinks slowly. Unfortunately, the sinking rate of fluorocarbon line is not significant enough to greatly influence the diving depth of fishing lures and trolling hardware.
Anglers who are interested in using fluorocarbon lines will benefit from the low stretch and high abrasion resistant properties, but can not expect to achieve greater depths than fishing with similar break strengths of monofilament, co-polymers or super braids.
The added cost of fluorocarbon lines makes this line option more practical as a leader material than as a main line. Lots of trolling situations are taylor made for using fluorocarbon line as a leader material including using leaders for diving planers, leaders on downriggers, tying harnesses or leaders on lead core and copper wire rigs.
The thickness of various lines varies greatly from manufacturer to manufacturer. In fact, the fishing industry has no standards for how thick a line should be for particular break strengths. It’s also true that in an attempt to better market their products, line manufacturers are constantly developing thinner lines with greater break strengths.
All this is good news for the troller who benefits greatly from thin lines that allow lures and trolling hardware to achieve maximum diving depths. However, a compromise of properties must be met to insure the species being targeted can be routinely landed without line failure. It would be fool hardy to target a powerful species like king salmon with an ultra thin 10 pound test Spectra braid that has the diameter of two pound test monofilament!
Minimum practical break strengths in fishing line should be adhered to when trolling. This standard of course changes depending on the type of fish being targeted. A general guideline suggests that for species including walleye and sauger a line with a break strength of 10-12 pound test is the smallest practical choice. Similar line sizes work well for in-land lake trout species, bass and panfish. For species that are often line shy like steelhead and brown trout, a middle of the road line in the 12-15 pound test range makes sense. Larger fish like king and coho salmon call for a minimum break strength of 15-20 pound test. Even heavier lines are needed for exceptionally large fish like stripers which require fishing lines in the 20-30 pound test range. Toothy critters including pike and musky require lines in the 20-40 pound test range for most trolling applications.
Line diameter as it relates to lead length is another topic trollers need to embrace. Inherently thinner lines allow lures to dive to deeper depths, but depending on how deep the fish are found, it may not be in the angler’s best interest to use ultra thin trolling lines.
Much of the time the fish being targeted can easily be reached using line that are not necessarily the most thin available. The rule of thumb is that so long as fish can be reached by using “reasonable” lead lengths, line diameter choices favor using somewhat thicker lines that are in turn more user friendly and forgiving of abrasion and failure. The key word here is “reasonable” because using exceptionally long trolling leads rarely puts more fish in the boat.
For most trolling applications it’s wise to avoid lead lengths any longer than 150 to 200 feet to achieve the desired lure depth. If it becomes necessary to use longer lead lengths, switching to a low stretch and ultra thin diameter braid makes the most sense.
There are other issues to be concerned with regarding line types and diameters. Many of the fishing accessories designed to benefit trollers do not function well when used with low stretch braids. For example, line releases commonly used with planer boards and downriggers are routinely designed to function with monofilament or co-polymer lines. Super braids are small in diameter and the surface of the line is slippery. Most planer board and downrigger releases use rubber pads that have a difficult time gripping super braid lines. Monofilament and co-polymer lines are routinely the best choice when using these trolling accessories.
Some after market line clips and releases are designed to function well with super braid lines. The cost of these releases is fairly high, but they do allow anglers the option of trolling with super braids for popular applications like planer boards.
It’s true that line diameter is a fundamental factor of trolling that plays a profound role in how deep a lure or trolling device will dive. Next to lead length, line diameter is the most important variable trollers must pay attention to. Still, the virtues of trolling with thin lines must be kept in perspective. Lines that are overly thin tend to suffer from abrasion quickly and fail at the worst possible moment. The best advice is to take the route of compromise and select lines that are as thin as practical for the trolling application at hand.
Most anglers believe that trolling speed has a profound impact on the diving depth of all things trolled. This statement is only half true. Trolling speed does indeed has a profound impact on lures and trolling hardware that sinks at rest. Sinking devices are highly “speed dependent and trolling speed has an overwhelming influence on how deep these devices will dive. In general, the slower these devices are trolled, the deeper they will fish. Conversely, the faster these devices are trolled, the higher in the water column they run.
Controlling lead length also has an impact on the diving depth of sinking devices, but boat speed is the dominate factor to be concerned with. Sinking devices that fall into this category are many and include the majority of diving planers, sinking style crankbaits, trolling sinkers like keel weights, snap weights, tadpole divers and sinking lines such as lead core and copper wire. Literally any fishing lure or trolling device that sinks at rest will be highly speed dependent, forcing the angler to monitor not only lead length and line diameter, but also boat speed while fishing.
The bad news here is that while lead length and line diameter are relatively easy variables to monitor and control, boat speed is not. Any angler who has watched popular trolling speed indicators such as speed over ground numbers on a Global Positioning System unit or a spinner wheel speed indicator has undoubtedly noticed that these devices don’t indicate a constant speed, but rather a speed zone that fluctuates up and down constantly.
The reason for this is simple. As a boat is moving through the water the course of travel is constantly changing a few degrees left and right. Every time the boat wanders slightly off course, the forward speed dips a notch or two. When the boat again lines up on course, the speed jumps slightly. Other factors such as wave action make it virtually impossible to drive a boat in a perfectly straight line further complicating the issue and leading to a situation that is a source of constant frustration for many anglers.
Controlling boat speed boils down to doing the best humanly possible and being satisfied with less than perfect results. This is precisely why lots of serious trollers install auto-pilot devices on their boats to aid in keeping the boat moving as much “on course” as possible. With the help of an auto-pilot an angler can do a pretty good job of controlling trolling speed, but can never achieve perfectly consistent speeds that in turn deliver precise and repeatable diving depths.
What all this mumbo jumbo means to the troller fishing sinking devices is it is humanly impossible to control the running depths precisely. Instead the angler must be content to troll at a variable depth range that keeps the lure or bait within an acceptable fluctuation variable. While it may be somewhat frustrating for the Precision Troller who wants to control lure depth at all costs, in fact speed dependent lures and devices tend to work in favor of the angler by literally “searching” the water column as they naturally rise and fall in relationship to the boat speeding up and slowing down.
Many trollers firmly believe this phenomena is responsible for triggering strikes and is in fact an advantage over being able to maintain a constant depth level. The Precision Trolling staff has spend countless hours on the water observing how lures that rise and fall in the water column routinely trigger more strikes than baits that maintain a steady and constant depth level.
Sinking lures and trolling devices vary greatly in terms of how pronounced they rise and fall in the water column. For example, a sinking crankbait like the world famous Countdown Rapala sinks at rest, but slowly. So long as trolling speeds are closely monitored and lead lengths maintained, this lure will not vary greatly in depth.
By comparison the Snap Weight produced by Off Shore Tackle is a popular in-line trolling weight that can be clipped onto the line at any location. Because the weight is localized and very much negatively buoyant, Snap Weights tend to range up and down in the water column aggressively even when modest fluctuations in boat speed are experienced.
Depth control is an important piece of the Precision Trolling puzzle, but it’s important to keep this bit of knowledge in perspective. Controlling trolling depth within an acceptable “range” of depths is often the best possible option.
Lures and diving planers that float at rest and dive when trolled are NOT speed dependent and in fact speed plays a very minor role in how deep these devices will dive. Most anglers have a hard time understanding this fact of trolling. At slow, medium and even fast trolling speeds floating lures like crankbaits achieve no more or no less depth, so long as lead lengths and line diameters involved are consistent.
Floating lures and diving planers are NOT speed dependent. The reason is by their very design floating crankbaits float at rest and begin diving as the lure is pulled through the water. Water pushing against the diving lip of the lure forces it downward in the water column. As more line is played out these devices continue to pick up additional depth. Eventually floating crankbaits reach a point of diminishing return and pick up additional depth only when excessive amounts of line are deployed.
Speeding up causes the crankbait to work harder and the vibrations created are literally telegraphed up the line to the rod tip. Common sense suggests that if the lure is working harder it’s probably diving deeper, but in fact what’s happening is something very different.
Increasing trolling speed causes the crankbait to work harder and in fact it is trying to dive deeper. However at the same time friction on the fishing line is increased at a similar level. One force is trying to push the crankbait deeper in the water column, while an opposing force (friction) is working to counteract any additional depth. The two forces cancel each other out and what ends up happening is increasing trolling speed does not increase lure diving depth.
The Precision Trolling staff has documented again and again that floating/diving lures and devices are not speed dependent. In fact, at all common trolling speeds the depths these devices will achieve is not altered in a measurable amount by speed. It’s lead length and line diameter that are the controlling factors of trolling floating/diving devices.
What trolling speed does influence is lure action. At slower speed most lures have a more subtle action compared to faster speeds. Varying trolling speed is often the key to “triggering strikes” and plays a pivotable role in trolling.
Varying trolling speed is one of the best ways to measure the activity level of fish. In general, fish activity level is closely tied to water temperatures. In colder water slower trolling speeds are normally required to trigger strikes, while in warmer water faster trolling speeds prevail. Certainly there are exceptions to this rule, but by and large it’s amazing how often this rule of thumb is accurate and dependable advice.
Simply changing trolling speeds can and does impart lure action changes which in turn can also trigger strikes. Most species of fish tend to strike at lures and baits most readily when they are presented at varying speeds instead of a constant speed. Most likely this plays to the predatory instinct all fish have in that a strike response is more likely to be stimulated when food appears to be escaping.
A LOOK AT HOW TO CONTROL TROLLING SPEED
The forward trolling speed of a boat can be maintained with the primary outboard, a small gasoline kicker engine or a powerful electric motor. For relatively fast trolling speeds ranging from 2.5 to 4.0 MPH, the primary outboard or I/O engine on the boat routinely can be used for trolling chores. In some cases a trolling plate that fits over the prop or sea bag that is dragged in the water must be used to slow the boat down enough to reach popular trolling speeds.
Modern four stroke, electronic fuel injection and high tech two stroke outboards tend to idle at slower speeds than the carbureted outboards of the past. What that means to the troller is in many cases the majority of trolling chores can be handled with the primary outboard. This simply wasn’t possible a decade ago when most outboards were designed simply for primary power.
Small gasoline kicker motors are a common sight on many trolling boats because they are stingy on fuel and do a magnificent job of delivering all the common trolling speeds. Not all boat types adapt to the use of a kicker motor on the transom. In many cases special brackets must be retrofitted to the boat to accept a small gasoline trolling motor.
Electric motors can also be highly efficient methods for controlling boat trolling speed. Traditional bow mounted electric trolling motors that featured cable steering systems were not practical for trolling chores as someone had to constantly steer the boat. In recent years the advent of remote control or auto-pilot style electric motors has allowed anglers to control the boat using a bow mounted electric motor from any location in the boat.
A second style of electric motor mounts directly to the cavitation plate of outboards and can be used to provide forward power. In this case the boat is steered by someone stationing themselves at the helm and making adjustments to the steering wheel as needed.
One of the huge advantages of electric trolling motors is they offer quiet and clean power and infinitely adjustable rheostat speed controls. This feature allows anglers to refine trolling speed down to precise levels. Compared to the linkage driven systems on kicker motors and primary outboards, trolling speed with an electric motor is much more precisely regulated and more importantly duplicated.
To troll for long hours however requires lots of battery power. Most fishing boats require at least a 24 volt electric trolling motor system and many anglers favor the larger 36 volt motors for serious trolling chores.
PUTTING IT ALL TOGETHER
To completely benefit from trolling anglers must intimately understand the variables that control this popular fishing presentation. Some of these variables are intuitive and others more difficult to fully understand, but that’s part of the attraction to trolling as a fishing method.
Because there are so many lure types and other devices readily adapted to trolling it’s always a challenge to stay on top of the trolling game. The ability to anticipate trolling depths and more importantly the ability to accurately “duplicate” productive combinations of lure type, lead length, line diameter and trolling speed is the secret to getting the most from trolling.
Of course experimenting with lure actions, colors and variables like trolling with or against the wind also play into the success an angler can expect. It’s safe to say that most anglers will never have enough time on the water to master all of the trolling methods or options available. Still, trolling is a mechanical process that’s relatively easy to teach to others and amazingly easy to digest.
Any angler who understands the fundamentals of trolling will be successful on the water. The more an angler learns about the finer points of trolling, the better able he or she will be to catch a wealth of species on just about any body of water.