Stalking Trout by How They See and Hear
Whether you are fishing a stream or a lake, there is without doubt a certain kind of ‘behaviour’ that you have to adopt if you want to catch fish.
What I’m talking about is the need to ‘stalk’ trout. Remember that trout are extremely shy and get ‘spooked’ by even the slightest unnatural movement on the river bank or lake shore.
When you are out fly-fishing on a river or a lake, you have to behave like a hunter! You have to make all your movements very slow, stealthy and deliberate. You have to hide behind trees and rocks as much as you can. You have to crouch down, close to the ground. And you have to be able to sit or stand perfectly still for long periods of time.
When stalking trout, it’s helpful to have some information about how they can detect you through their eyes and through their sense of smell.
How Far Can Trout See?
Here is a diagram that illustrates the trout’s field of vision.
As you can see, the trout has quite an extensive field of vision, but there are areas where he has no vision at all. We can think of these as the trout’s ‘blind spots’.
You’ll notice that trout have a major blind spot directly to the rear of their bodies. This means that when stalking trout, you should – if it’s at all possible – approach trout from behind. In a river, this means approaching each trout from a position directly downstream of where it is lying.
But when you’re fishing a lake, it may not be possible to get yourself behind the trout all the time. Thus on a lake it is even more vital that you keep your body low down at all times while stalking trout.
From the diagram, you should also be able to gain the impression that the farther away from a trout you are, the less likely it is that he will see you.
This is because the trout’s field of vision conforms basically to the shape of an inverted cone, especially above the surface of the water. This is why it is important to stay as far back from the water as you can, and keep a low profile if you haven’t got cover.
This is particularly true with lake fishing. Trout in lakes end up facing in all different directions as they cruise around looking for food. Even if a trout is swimming straight toward you on the bank, you won’t fall into its field of vision unless you are either too close to the water’s edge, or standing up too tall.
Trout can Hear, too !
You also need to be aware that trout have an extremely acute ability to hear things underwater. By ‘hear’ I mean that trout pick up vibrations. Trout have vibration receptors on their bodies, which they use to locate food at night or when the water is discoloured. But trout also use their vibration receptors for identifying danger.
If you walk through a stream too quickly and thus disturb rocks and stones on the streambed, you will create vibrations in the water that any trout in the vicinity will immediately detect.
Similarly, if you drop something like a fly box onto the bottom of your boat, vibrations will radiate out into the lake around you, potentially scaring all the fish. So at all times you have to be careful not to create vibrations in the water you are fishing.
If the trout sees or hears you at any point, it’s all over! You won’t catch him! Trout are extremely timid and will adopt evasive behaviour at the smallest hint that danger is present.
But if you can creep up on the trout and cast a fly to him without revealing your presence on the bank, you may well have him in your landing net within a matter of minutes!