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Home Trout An Insight to Trout Mentality

An Insight to Trout Mentality


Understanding Trout Mentality


Osprey with a Trout





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   Although trout are not particularly intelligent by human standards, catching them is difficult at best and nearly impossible at worst. Therefore, in order to be successful, an angler must first understand the basic aspects of a trout's life. For instance, what predators do they face each day and how do they avoid them? What does the world look like to a trout? What is it like to have live in an environment that constantly grows and shrinks and speeds up and slows down with rising or falling water levels? How do you obtain enough food to grow when you have to expend energy fighting a current your whole life? Learning the answers to these questions will help you to understand what it is like to be trout and will inevitably make you a better angler.


How to Think Like a Trout -


     When I was little kid, I was out fishing with my father one day and I distinctly recall asking him how to catch fish and, I remember him looking at me with an introspective look on his face as he said to me “if you want to catch fish, then you need to learn how to think like a fish”. Now, at the time, I really didn’t understand what he meant by that statement but, since he was a truly excellent fisherman, I took his words to hart. However, it was not until I was in my early twenties that I began to fully comprehend what he meant by that statement. Now, I literally consider it to be one of the most profound pieces of fishing advice I have ever received or read. In fact, I now consider it so important that I incorporate it into each and every one of my fly fishing excursions and I teach it to each one of my novice and experienced fly fishing clients. However, since I specialize in guiding back country fly fishing trips for wild mountain trout for experienced clients and fly fishing instructional trips for stocked trout on big water for novice clients, I will focus this article specifically on trout. But, be aware that this point of view applies to all fish species found everywhere around the world in both fresh and salt water.


     Thus, in order to learn how think like a fish, you must first understand the fish’s world. Consequently, from the moment a trout is born as an egg on the Redd, there is something in the water that would like to make a meal of that trout twenty-four hours a day, seven days a week, 365 days a year such as, Dace, Sculpins, Chubs, and even adult Trout! In addition, as the trout grows from an Alevin, to a Fry, to a Fingerling, to a Parr, to a Juvenile, aerial predators such Herons also become a major threat. Consequently, if a trout is to grow to maturity, it must learn to become VERY paranoid. Therefore, I have this comical vision in my head of all the trout everywhere getting together in a huge Trout convention where they all discuss the subject of predators and they have all come to the conclusion that, if it moves, RUN!!! If it doesn’t move, RUN ANYWAY! Thus, if a trout sees any movement whatsoever within its cone of vision, his first instinct is to dart into the nearest Sheltering Lie and stay there until he feels like the threat has passed. So, as a fly fisherman, it is absolutely imperative that you learn to become very stealthy in your approach to a prospective trout lie. In fact, when fly fishing for trout, I find it helpful to adopt the attitude of a hunter rather than that of the average fisherman. Therefore, I use any available cover to hide my approach to a prospective trout lie such as moving along the bank where I am hidden by trees instead of wading up center of the stream, hiding behind boulders, crouching down so that I am below the trout’s cone of vision, and I have even been known to lay down and crawl on my belly in really exposed areas. In fact, I recall one particular instance where I was fly fishing on avery small stream called Boone’s Fork here in the Blue Ridge Mountains when I spotted the ultimate trout lie beneath an undercut bank in the bend of the creek. However, the banks were very steep on both sides of that creek and thus, approaching and casting from the bank would have exposed me to any trout hanging out in that lie. So, instead, I walked upstream a bit, dropped down off of the bank in to the water, then crouched down and waded to the upper end of a sand bar in the center of the stream where I then got down on my belly and crawled up to within casting distance of the lie. Then, I very carefully cast my dry fly onto surface of the current just above the bend and, as it passed that undercut, a very large Brook Trout darted out and seized my fly! Thus, was able to catch and land a very nice trout for that particular stream. But, had I chosen to approach that lie in any other way, the trout would have seen me and retreated further into the undercut and refused to come out to take my fly. Consequently, being aware of how a trout thinks and understanding their world from their point of view enabled me to plan and execute my approach to that lie and enabled me to catch a beautiful, wild, Brook Trout which was an accomplishment that I was very proud of.



How a Trout Sees the World -


     While understanding how fish thinks is instrumental in enabling you to catch fish, it is also important to understand how they see their world. Thus, the following description applies to all fish species in any type of water. However, for the purposes of this article, I will focus specifically on Trout.


     So, first imagine that you are a tout hanging out in your favorite tout lie in the stream. Thus, if you were to look up, what you would see is a huge mirror hanging over your head and that mirror would reflect an exact replica of the stream bed and anything located beneath the surface of the water. However, you would also see a round hole in this mirror located directly above your eyes that allows you to see the world above the surface of the water. The cause of this phenomenon is a law of physics called Snell’s Law that states “any light waves striking the surface of water at an angle that is greater than 45° will enter the water and, any light waves striking the surface of water at an angle that is less than 45° will be reflected”. But, unless you are holding in perfectly still water, the image of the surface world you see through this window will be distorted by the current and any waves caused by riffles or runs. Thus, if you were hanging out in white water (as Rainbow Trout often do), then instead of seeing an image of the surface world, you would instead see a white froth of air bubbles. In addition, the size of the hole through with you see the surface world would depend on the depth at which you were holding because, the diameter of the hole through which you can see is two-and-one-quarter times the depth at which you are holding. Therefore, if you were holding at a depth of two feet, then you would have a round window over your head approximately four and one half feet in diameter through which you could see the surface world. In addition, because the shape of this hole extends at a 45° angle from either side of the trout’s eye (with the apex of the angle being located at the tout’s eye), trout have 90° of verticalvision under the water’s surface. However, once the edge of this angle reaches the water’s surface, it lowers to a 15° angle. Consequently, trout actually have 150° of vertical vision which is shaped like a cone extending upward from their eyes and thus, we call this the “Cone of Vision”. Therefore, a fly fisherman approaching a potential trout lie will only have a 15° angle from the surface of the water in which to approach the trout unseen.


     However, it is important to keep in mind that since this is an angle, it widens accordingly the further you are from the apex located at the water’s surface and narrows accordingly the closer you get to the apex at the water’s surface. Therefore, the farther you are away from where a trout is holding, the less likely it is that he will see you. But, the closer you get, the more likely it is that he will see you. Thus, the average fly fisherman of average height wading in water that is approximately waist deep will only be able to approach a potential trout lie to within about fifteen feet without being seen and even less if you walking along the bank even with, or above, the water’s surface. So, if you feel the need to approach the trout’s lie any closer than this, you will need to crouch down closer to the water’s surface or, use any available cover such as rocks or boulders to hide your approach. In addition, it is also important to keep in mind that trout have 330° of horizontal vision beneath the surface of the water which leaves a 30° blind spot directly behind them. Thus, since trout are anatomically designed to face upstream into the current, it is always best to approach a potential trout lie from downstream so that you approach them within their blind spot.


     Last, while trout do have rudimentary ears and thus, they can hear some sound beneath the water’s surface, they have a far more sensitive organ called the “Lateral Line” which extends the length of their body from head to tail that consists of a group of highly sensitive nerves that enables them to feel or “see” pressure waves in the water. Thus, when you are wading in the water and approaching a potential trout lie, it is imperative that you do so in as stealthy a manner as possible and as slowly as possible in order to minimize the pressure waves crated by your body moving through the water.


     Consequently, approaching a wild trout in its natural environment without being seen or felt is a daunting task at best and one that takes years of practice to perfect. Therefore, in my opinion, anyone who is able to approach a wild trout, then cast their fly precisely enough to land it within the trout’s “cone of vision”, and then cause that fly to drift in a way that looks entirely natural to a wild trout and thus entices it to strike the fly, has accomplished a phenomenal feat of planning and stealthy execution of which they should be extremely proud regardless of the size of the trout they catch!




A Trout's Cone Of Vision



The Anatomy of the Water Column -


     As a fly fisherman, it is important to understand the anatomy of the water column and how it affects you fly as it drifts with the current. The reason this understanding is important is because the different levels of the water column move at different rates of flow and thus, one or more of these different levels can adversely affect you fly in such as way that it appears to be unnatural to any trout viewing it as a potential meal.


     Consequently, in order to understand the water column and how it affects your fly as it drifts, it is important to understand that the water column is divided into three different zones or layers called the surface, the center, and the bottom of the water column. Therefore, in order to provide yourself with a mental image of the water column’s anatomy, imagine that you are standing in the middle of a stream and that you are facing upstream. Then, imagine slowly lowering yourself to the streambed and then fully immersing yourself under the water while still facing upstream. Therefore, what you would see is the streambed containing the water as it flows toward you and that streambed would appear to be roughly U shaped. Then, you could mentally divide the water’s flow into three sections consisting of the surface of the water, the water just beneath the surface to just above the streambed, and the water flowing adjacent to the streambed. Thus, if you examined these three different sections carefully, you would see that the water on the surface of the stream is flowing slightly slower than the water just below it because of the friction between the water’s surface and the air just above it. Then, you would also notice that the water in the center of the water column is flowing faster than the water on the surface of the stream because there is no impediment to its flow. However, you would also notice that the water flowing adjacent to the bed of the stream was the slowest layer of all because the water flowing in this layer is impeded by rocks, gravel, and aquatic plants.


     Now, the reason that this knowledge is important to a fly fisherman is that we commonly use four different categories of flies and each one of them is specifically designed to drift in one of these three zones in the water column. For instance, Dry Flies are specifically designed to drift on the surface of the water as the name implies. However, both Wet Flies and Streamer are specifically designed to drift in the center of the water column. Whereas, Nymphs on the other hand, are specifically designed to drift in the layer of slow water at the bottom of the water column. But, in order to appear natural to the trout, each of these four different types of flies must drift in the current without any drag. Therefore, if you are fishing with dry flies and the intervening current between you and you fly causes your fly line to move downstream faster than your fly, it will cause a small, V shaped, wake to appear behind your fly (called “boating”) which will cause the fly to appear unnatural to the trout and thus they will ignore it as a source of food. In addition, if you are fishing with wet flies in the center of the water column, then the surface currents can have the same adverse effect on you fly by pulling your fly line downstream faster than your fly is drifting which again, causes it appear unnatural to the trout. However, if you are fishing a nymph in the layer of slow water at the bottom of the water column, then you have two layers of faster moving water above you fly that that can adversely affect its drift. Therefore, a special technique known as “mending” is often necessary to reset your fly line on the surface of the water so that it is positioned upstream of your fly in such a way that the fly line does not drift faster than the fly and thus, cause you fly to appear unnatural because it is being dragged downstream by the fly line.


     Thus, it is very important for all fly fishermen to be aware of the anatomy of the water column and its three different layers or zones and how a fly line laying on, or extending through, each of the different layers can adversely affect a fly’s drift by causing it to appear unnatural to the trout.



A diagram of the anatomy of the water column


Figure 1


     Now, the reason that this knowledge is important is that there are four different classes of flies that fly fishermen use (dry flies, wet flies, nymphs, and streamers) and  each of them is designed to be fished a different section of the water column. For instance, Dry Flies are meant to be fished on the water's surface while, Wet Flies and Streamers are meant to be fished in the center of the water column, and Nymphs are designed to be fished in the bottom of the water column. However, all too often, neither the water on the steam's surface nor the water below it flow at the same rate and thus they create disparate currents and whenever the water encounter obstacles, these obstacles create both turbulence and eddies. Consequently, this disparity in the swiftness of the surface of the water as well as the varying sections of the water column beneath it can inadvertently cause drag on your fly resulting in an unnatural drift that is not apparent to a fly fisherman but, which is very apparent from a trout's point of view; thus causing them to refuse to take your fly.


     In addition, it is also important to remember that the bottom of the water column is where a  Trout is most comfortable and thus it is where they spend the large majority of their time. The reason for this is the layer of slower water that exists there which allows them to expend little or no energy to maintain their position in the stream in addition to the abundance of aquatic insects that live among the substrate. Consequently, Trout are far more inclined to feed within their comfort zone but, they will rise through the water column to take a morsel of food if the reward vs. risk is great enough to warrant exposing themselves. Therefore, fly patterns that are designed to be fished either just above the bottom of the streambed (nymphs) or in the middle of the water column (wet flies and streamers) tend to be the most productive. However fly patterns designed to be fished on the surface, even they are the least productive patterns most of the time, are also the most exciting patterns to fish because you get to see the Trout come up for the fly and because of the predatory anticipation and lightening-like reflexes required to actually hook the fish.



The Food vs. Energy Equation - 


     As I mentioned in a previous article titled “How to Think Like a Trout”, trout are first born as an egg and then, as they mature, they grow through different stages based upon their size called Alevin, Fry, Fingerlings, Parr, and Juveniles before becoming sexually mature and thus being classified as Adults. Consequently, once a trout completes the Alevin stage by completely consuming its yoke sack, the only two things on its mind are avoiding predators and finding and consuming enough food to grow larger.

     Consequently, all trout look for quite spots in the stream called “lies” where they can escape the constant pull of the current and yet have easy access to food without unduly exposing themselves to danger from predators. Therefore, such places as eddies located behind rock or a log adjacent to good current flow make excellent “prime lies”. In addition, it is important to learn to identify prime lies because you will always find the largest trout in the prime lies. Now, the reason for this is a concept called the “food vs. energy equation” which states that, in order for a trout to grow larger, it must gain more energy from the food it consumes than it expends in pursuing and capturing that food. Thus, I like to think of the stream as a floating restaurant and the various aquatic and terrestrial insects drifting in the current as the menu and trout’s “prime lie” or “feeding lie” in the stream as their seat in the restaurant. So, when a tasty looking insect comes drifting downstream towards a trout’s “prime” or “feeding” lie, all a trout has to do is decide whether or not he wants to dart out into the current and capture that insect. However, it is important to be aware that there is also numerous bits of organic debris drifting in the current along with all those tasty insects and thus, a trout must become very adept at discriminating what is actually edible from what is not edible and they learn to do this by learning to identify the size, shape, and color of the available species of insects that inhabit or fall into their particular stream. In addition, they also look for signs of movement such as the gills located along the abdomen of May Fly nymphs as an indicator of life because any trout that mistakenly captures non-edible food is wasting energy. Plus, any trout that spends time swimming in the current to capture food is also wasting energy unless there is a tremendous amount of food drifting in the current such as when a May Fly hatch is occurring. Thus, when such hatches do occur, trout will often leave their sheltered “prime lies” and hold in the center of the water column in the middle or tail of a pool in “feeding lies” in order to more easily capture these nymphs and the emerging Duns. But, this exposed position also makes them far more vulnerable to aerial predators and thus, they are often very skittish when they are in “feeding lies”. However, the overabundance of food drifting in the current often makes the extra risk well worth the danger.


     Now, in addition to the various species of aquatic and terrestrial insects drifting the current, there are also numerous species of small fish inhabiting the stream along with the adult trout such as Dace, Sculpins, and Chubs, and Crayfish along with trout in the various stages of maturity, and all of them are fair game as far as adult trout are concerned. Thus, I like to think of these various bait fish in this manner: if someone were to offer you your choice between a free McDonald’s cheeseburger and a free 20 oz. steak dinner, which one would you choose? Personally, I would choose the steak dinner and most adult trout seem to feel the same way. So, although it obviously requires more energy to run down and capture a bait fish, that bait fish provides FAR more energy than consuming a couple of nymphs or dry flies. Therefore, trout will always consume the largest meal available as long as it provides them with more energy than they expend capturing that piece of food. Consequently, larger flies tend to catch larger trout.


     But, it is also important to understand that when there is an overabundance of nymphs and duns drifting in the current such during a hatch, then trout will often become very selective in what they choose to eat for the duration of that hatch. Thus, they will often ignore any food item that is not the same size, shape, and color of the hatching insects because they have already determined through sampling that that particular insect is an edible source of food and thus it satisfies the food vs. energy equation.



food vs. energy - small





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