06/27/12

Insects and other foods the trout should be eating:
Hatching:
1.    BWOs (Eastern)
2.    Green Sedges (Caddisflies)
3.    Cinnamon Caddis (Mostly Abrams Creek)
4.    Cream Cahills
5.    Little Yellow Stoneflies (Little Summer Stones)
6.    Sulphurs
7.    Slate Drakes
8.    Little Green Stoneflies

Most available/ Other types of food:
10.  Sculpin, Minnows (Streamers)
11.  Inch Worm (moth larva)
12.  Beetles
13.  Grasshoppers
14.  Ants

Fishing Low Water Levels
There's two main factors you have to consider when you are fishing low water levels in the
park. One is the fact the
trout tend to be more cautious and easy to spook and the
other is the fact
low water means slow water.

Few anglers consider the fact
the slower moving water allows the trout more
opportunity to examine your fly.
In higher, faster moving water they only get a split
second glimpse of your fly in most cases but in slower flowing water, they get a much better
view of it. This not only makes the appearance of the fly more important, it also makes the
presentation of the fly more important. In order to deal with this effectively, it's very important
for you to understand just how a trout sees your fly.
Today, I will go over some points about
how the trout can see you, the angler.
Tomorrow, I will go over how the trout views your fly.
We all have strong tendencies to consider things from a human perspective meaning we
envision the trout seeing the fly as we think we would see it. The facts are trout don't view
things the same way would do.

How the trout see you:
Trout have a much larger area of peripheral vision than humans. Humans have a much
larger area of binocular vision that trout. While trout can see almost all the way around their
body, humans can't. Some birds can see all the way around themselves without moving their
eyes. We have large blind zone behind us. A trout only has about a 30 degree angle of area
directly behind them that they cannot see. The have a 330 degree area of peripheral vision.
We see an area of about 200 degrees of peripheral vision, meaning we cannot see an area
behind us of 160 degrees.  Within a 120 degree zone of vision, we can see most things
clearly because our binocular vision represents 120 degrees of it. Only 60 degrees of the
total is peripheral vision, or thirty degrees on each side of a line straight ahead.

Trout can detect movement of objects within about a 330 degree area. The small 30 degree
area they cannot see at all is called the trout's blind zone. If the trout is not swaying its head
back and forth, an angler in the blind zone isn't visible to the trout. That's one reason it's
important to approach the trout fishing in an upstream direction. Thirty degrees is a small
area. Trout in a stream ahead of you, but to your left or right a few feet of directly ahead of
you, most likely can see you. They can't see you clearly but they can detect your movement
very easily. If they are swaying their head much, looking for insects drifting downstream,
although you may appear as just a big blob, you movements are visible and noticeable to the
trout. In this regard and only in this regard, it's almost impossible to slip up behind a trout
without them being aware of it; however, there's another big factor involved.

Trout see everything above the surface of the water through a circular window that's directly
overhead of their eyes. Everything else above the surface is seen by the trout as a mirrored
image of the bottom and structure in the water. In other words, they cannot view anything
outside of that circular window of vision that's above the surface. The diameter of this window
is 2.26 times the depth of the trout. The deeper the fish, the larger the window. This window
doesn't give them a clear vision of anything seen within it. Objects outside the water that
appear near the edge of this circular window are distorted. They are much shorter and wider
than they would be in clear focus. Objects directly overhead in the center of the window are
in focus and not distorted. If the surface of the water is riffled, or rough, the window is still
there, but the view the trout's gets of objects outside the water are blurred by the tiny waves
of rough water. If an angler appears near the edge of the window, his or her movements are
blurred and greatly distorted. The bottom line to this is a trout cannot see things above the
surface of the water as clearly through a surface disturbed by ripples of water, or tiny waves,
as they can through a perfectly calm surface. Trout holding in riffles cannot see you as
clearly as trout holding in water with a smooth surface.

There's yet another big factor that affects the trout's vision of an angler. This one is very
important to anglers because it provides them a way to get close to trout without being seen.
When light waves strike the surface of water below a ten degrees angle above the horizon,
about eighty-five percent of them skip or bounce off the water. This is called glare. Although
this reflected light or glare, doesn't get to the trout’s eyes and doesn't affect the trout’s
vision, it does bother anglers that are outside looking in the water. This is why polarized
sunglasses help you see under the water more clearly. They cut this glare. Although I
mentioned it with regard to your view of objects in the water, It also has a huge effect on the
trout's view of objects outside of the water through their small window of vision.

An object outside of the water that’s below a ten degrees angle (ten degrees above the
horizontal or 180 degrees) appears very dim and not well lit like other objects within the
trout's window of vision and is hardly noticeable to the trout. In other words, an angler that’s
below this ten degrees angle is not visible to the trout.

If an angler is thirty feet from the fish’s window of vision, this ten degrees angle will be five
feet, three and one-half inches above the surface of the water. If a person standing level with
the water is only five feet tall, he or she isn't visible to a trout. In other words, if you want to
get close to a fish, you can certainly do so by staying below this ten degrees angle. You can
kneel down to do this or you can get even closer by crawling up close to the fish. Few
anglers are going to get on their bellies and crawl up to a fish. There's also few places where
the water is almost level with the bank. In other words, the higher the angler is on a bank, the
more difficult it is to stay below this ten degree angle.

If you’re wading, only the part of your body that’s above the water counts in regard to the
window of vision. This means you can get much closer to the fish wading, provided you don’t
spook it otherwise. At fifteen feet from the fish, this distance becomes two feet, seven and
three-quarters inches. A five-foot tall person wading in waist deep water, fifteen feet away
from a trout would be hidden from the its view.

Keep in mind I'm only pointing this out to give you a rough idea of how the trout sees things
outside of the water. I'm sure you have determined that the lower you stay, the closer you
can get, something most all anglers know, but few know why and few know how to determine
the limits of the areas the trout can see you or yet better described, detect your movement.

Now, I'm sure your thinking that getting below this ten degree angle isn't very practical. You
are right but there's another important factor to it. For example, an angler that’s thirty feet
from a trout holding near the surface, located at a twenty to thirty degree angle above the
horizon, would appear very short and fat to the trout. As mentioned above, this is because
objects near the edge of the window of vision are greatly distorted. Never the less, the fish
could see the flattened out image of the angler. Although the angler may look like a big toad
frog to the trout, If the angler (toad frog) suddenly moved, it would most likely spook the
trout. But again, if the water is rough or riffled, the fat and short appearing angler would
been seen by the trout as a very blurred image. The angler's movements couldn't be
distinguished from the movements of the edge of the window of vision caused by the rough
water. The bottom line to this is that if the water is rough, you can get even closer to a trout
without it detecting your presence. The lower you are and the rougher the water is, the
closer you can get without being detected.

There's even more factors involved, such as the amount of available light, how well you
blend in with the background, movements you make like casting, sound and ripples of the
water made wading, etc.

There's one thing for certain. If you are going to fish the streams of Great Smoky Mountains
anytime soon, meaning while the water levels are low, you better understand this or you will
find yourself "spooking" instead of "catching".

Tomorrow, I will go over facts that affect how a trout sees your fly.
Copyright 2012 James Marsh