Insects and other foods the trout may be eating:
1.    Blue-winged Olives
2.    Little Sister Caddisflies (Abrams Creek)
3.    Little Yellow Stoneflies -Summer Stones
4.    Slate Drakes
5.    Cream Cahills
6.    Little Green Stoneflies
7.    Ants
8.    Inchworms
9.    Beetles
10.  Grasshoppers
11.  Hellgrammite
12.  Cranefly
13.  Sculpin, baitfish and small crayfish (Imitate with streamers)

Advice on Fishing Techniques, Strategies and Methods - Part 3

Have you ever heard that fish avoid the sunlight because they do not have eye lens
and that the bright sunlight hurts their eyes? I have read that over the years many
times; however, it's one of those things that's only partially true. Fish don't have eye
lens but the light from the bright sun doesn't hurt their eyes. Common sense should
tell you that. If it did, they would avoid the bright sunlight and many species of fish
don't avoid the bright light.

Some species of fish do avoid the bright sunlight but not because it hurts their eyes.
They avoid it for other reasons. They prefer to hide from their predators in the dark
shaded areas of a stream, or they prefer to hide as predators themselves. Many
species of fish have excellent low light level vision compared to their prey. These
fish prefer to feed during low light levels.
The brown trout is one of those
species of fish.

The eyes of a fish are round. Their two round lenses is what allows them to see
clearly under water. The human eye lens is flat and when opened under water,
things become blurry because of that.

Some of you may think I am nuts but I will go so far as to say that large brown trout
feed more like largemouth bass than rainbow trout. Largemouth hide in cover,
under a log or in a thick bush and use the element of surprise to attack their prey
consisting mostly of other fish. They prefer low light levels because it gives them the
advantage over fish they like to dine on. This has been proven over and over
during large bass tournaments. When there's a low pressure system, versus a high
pressure system, the overall number of fish weighted in is always much higher. Low
pressure systems bring clouds and sometimes rain whereas high pressure systems
typically bring clear, bright blue-bird skies. There aren't any such brown trout
tournaments, but I would assure you the results would be similar. Brown trout prefer
to feed at night and in low light levels.

During a bright, sunny day using polarized glasses, try spotting trout from some of
the high banks along the streams in the park. Remember, the higher you are the
easier it is for the trout to spot you, so stay hidden from them. See how many
rainbow trout you see out fully exposed to the sunlight versus how many large
brown trout you spot. I venture to say you will find some rainbows, but not the first
large brown trout. Just to qualify what I mean by large brown trout, lets say one over
14 inches. The only time you may spot a large brown trout under these same
conditions is during the spawn when they lose much of their caution. You will often
spot rainbows directly exposed to the sunlight, even during the middle of the day.  
Sometimes they will be in a feeding lane eating emerging aquatic insects and
sometimes just looking for food coming downstream along the bottom. Sometimes
they will be holding shallow and other times they will be holding in deeper water.
Often when you spot a rainbow in the bright light, it will be its shadow on the bottom
you are actually looking at.

A large brown trout captures its prey more like a cougar or leopard. It relies on low
light conditions to hide and pounce on other fish and crustaceans. They too use the
element of surprise much like a largemouth bass. You will find the large browns well
hidden during a bright sunny day. They will be underneath the crevice of a large
boulder, undercut banks, or anywhere they can find to hide out of the direct
sunlight. The are mostly nocturnal, meaning they feed mostly at night or in very low
light conditions such as very early or late in the day and sometimes during dark,
cloudy days. In the Smokies, they may tend to roam around and feed in dingy or off
colored water during the day, but rarely, if ever, under clear water conditions.

The rainbows are more like the cheetah than a cougar or leopard. They don't hide
and attack their prey. They will feed right out in the open water and they will do so
smack in the middle of the day in bright sunlight. Now I should stop and say that this
doesn't mean that rainbow trout will eat more or even as much on a bright clear day
as they will on a dark cloudy day. They will generally eat more on the low pressure
system days but it isn't because of the light's effect on their eyes. It's because most
species of aquatic insects prefer to hatch under low light conditions. Again, this
doesn't mean that the aquatic insects don't hatch on bright clear sunny days,
because they do. They just don't do so with the same intensity as they do on cloudy
days. You will often find a particular species hatching during a time span of a week
or two when there are not any low pressure days. They just string out the hatch to
last longer and there's almost always less insects hatching. Of course this is also
affected by the time of year (low sunlight levels) and time of day the particular insect
hatches. The rainbows could care less. They will feed on them in the bright sunlight
or under the shade of cloud cover.

When the weather is hot and someone tells you that you should only fish the
shaded areas of a trout stream during the day, they may well be lowering and
possible even eliminating your odds of catching rainbow trout.
That is poor,
misleading advice.
Most trout streams, certainly the ones in Great Smoky
Mountains National Park, are flowing and usually rather fast. The water temperature
is the exact same in the shady spots as it is in the bright sunlight. If you don't
believe this, just measure it for yourself. I have many times and I always find there is
absolutely no difference in temperature. By the way, I also have a very expensive,
professional water thermometer that I have used to test water temps although that
isn't something I carry around to use fishing. I am just pointing out the instrument is
accurate to within a tenth of a degree F.

Any angler that has fished very much knows that rainbow trout will feed in the open
water in the direct sunlight at times. I would venture to say that I have caught at
least a thousand rainbows doing just that and probably many more. I couldn't say
that about the brown trout, although the small brown trout will sometimes feed much
like the rainbows. I have caught plenty of larger, wild, brown trout on the surface on
a dry fly (not in the Smokies) from streams like the Big Horn, but that is usually not
the case. I don't remember having caught many large browns feeding on insects
during the bright sunlight but it happens. They will do just that when the large
Golden and Salmonflies are depositing their eggs during the day on some streams.
However, even then, you will find the brown trout will feed much more aggressively
during low light conditions. In the Smokies, large brown trout feed on other fish,
nymphs and crustaceans. They don't normally do this on the surface in bright light.
By the way, brown trout were brought into this country from Europe. They are not
native to North America. Rainbow trout are native to North America. They are
(should say were) native to streams that flow into the Pacific Ocean from the Rocky
Mountains. I'm just pointing out more differences. Also, don't forget, in the article
above,  I am only referring only to wild, or streamborn trout, not stocked trout.