Insects and other foods the trout should be eating:
1.    BWOs (Little)
2.    Cream Cahills
3.    Little Yellow Stoneflies (Little Summer Stones)
4.    Slate Drakes
5.    Little Green Stoneflies
6.    Mahogany Duns

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

Mahogany Duns - Dun
I remembered writing something about a fishing trip to the Smokies a few years back that involved
the first time Angie and I discovered Mahogany Duns in the streams of the Smokies. I found it but
didn't have any idea it was actually the very first article I had written for this website. The article is
about the spinner stage of the Mahogany Dun and this is about the dun stage but I will go ahead
and include it now. This is the article:

Late Summer Paralep Hatches (5/12/07):
It was late August of 2003. Angie and I had just returned from a month and a half
trip to Montana and upper Michigan. It was our first time in the Smoky Mountain
National Park in almost two months. We had fished unsuccessfully for a couple
of hours near Elkmont. Out of drinking water, we made a run for Townsend just
outside of the park for some water. Coming back into the park, we took a detour
to the Middle Prong. It was getting late and I thought we could get a few cast in
on the upper part of the Middle Prong of the Little River quicker than I could
reach the upper part of the main prong. We stopped near the end of the gravel
I had no idea what the water temperature was. Checking it, I found out it was 67.
This is better than I guessed but still on the high side of that preferred by trout. I
began casting a dry fly into the fast runs.
In a few minutes, I noticed that Angie was trying to catch some small mayflies in the
air. She exclaimed that she had caught a Trico. I responded by telling her there
were no Tricos on the Little River at that location and  tried to tell her that it must be a
little Blue-winged Olive. She said the wings and most of the body was clear. I
then said that it was probably a Jenny Spinner or small blue-winged olive
spinner. Then I noticed the air was full of them dancing up and down. She
brought one over and I discovered it was a
Paraleptophlebia species, not a
blue-winged olive.
This is the same thing we see in February and March except they are not the
adoptive species. These were mollis or maybe another species of that genus.
Some people call them Blue Quills and other call them Mahogany Duns.  They
were tiny, a hook size 18 or maybe even a 20. These mayflies behave the same
way as the early season blue quills in that they both hatch, deposit their eggs
and fall spent in the slower moving shallow water.
I changed to a blue-winged olive spinner pattern (all I could find in my fly box at
the time) and the results was amazing. Both the blue-winged olives and the Mahogany Dun
spinners have a rusty colored tint to them. Within the next 45 minutes or so, I caught
about a half dozen rainbow trout ranging from four to eight inches long. All I had
to do was cast it in the slow water or eddies.
Getting very close to the water revealed the tiny spinners. They are almost
impossible to see on the water unless you do get very close to it. You don't see
the trout taking them either. In fact, I didn't realize that I had about half of the fish
hooked until I began to pick up the line. One went airborne as I was attempting
to make a cast not aware that I had a fish hooked.  
At the time, I only had to tie on a three foot long 6x tippet. I already had a 9 foot,
5x leader tied on one of our rigs. This combination worked okay.  This is about
the right rigging for fishing these tiny spinners. Certainly nothing shorter or
larger would work well.
You want to make cast into the calm water areas -the ends of pools, eddies,
pockets behind rocks, etc. The fish will just sip the spinners and you may not
notice the takes at all. It is about impossible to see you fly. You just have to
watch for a small swirl or your line to move. The trout are remaining in one area
and looking for the spinners, so if you don't get a take in one place, try another.
It is also not easy to keep from spooking the trout. Stay hidden, move very slowly
and make rather long cast compared to the normal cast you would make in the
Smokies. That isn't always easy to do on the small streams. A bush or tree limb
can get your fly about as well as the trout can.
Just remember, that even in the dog days of summer, mayfly hatches may occur.
Everyone has probably seen the tiny mahogany duns and just thought they were
knats or midges. Many anglers may not have noticed them at all. Most anglers
were probably home thinking fly-fishing in the Great Smoky Mountain National
Park was dead until Fall.

Mahogany Dun - Dun:
An imitation of a Mahogany Dun is an exciting dry fly to fish. One reason is that the emerging duns
are usually located in shallow, calmer water as opposed to fast water runs and riffles. They prefer
calmer water to emerge.

When the duns hatch, they usually float a rather short distance on the surface of the water before
flying away but this depends on the particular species and the time of year it hatches. Normally the
water is fairly warm and their wings dry rather fast. This is unlike their close relatives, the Blue
Quills that hatch in the early Spring.

Up and across presentations of the Mahogany Dun usually work best but if the water is slow
moving and very slick or smooth, you may want to use a down and across presentation to get the
drag-free drift you need. As we said in the emerger section, these mayflies often hatch near the
banks and behind boulders where the water is calm and sometimes very shallow and clear. In
those cases you almost have to use a down and across or directly downstream presentation for
the fly to be effective.

Much depends on whether it is an Eastern or Western species of Mahogany Dun. The
water conditions vary greatly depending on that. In either situation, however, our dun has
proven to work time and time again. The way it should be fished will vary so you have to
adapt to the local stream conditions.
Copyright 2012 James Marsh