Smoky Mountain Stream Journal:

Stream Conditions (8/26/07):
We are still getting a large amount of email from concerned anglers -too many
for us to answer individually. While the drought conditions have let up in
Yellowstone  
www.flyfishingyellowstonenationalpark.com they have not in the
Smoky Mountains.
We have not fished in the Smokies since our last report because we have been
in Florida for the past week. We did go to the park and take the water
temperature at several locations yesterday during the late afternoon. It was not
good anywhere we checked from the lower Little River, Little River at Elkmont,
lower Middle Prong of the Little Pigeon River and lower West Prong of the Little
Pigeon River. It was not even good far upstream almost to the top of Walker's
Camp Prong. There the temperature had reached as much as (68 degrees F.)
where we checked it and it was extremely low. Catching trout could not be easy
anywhere on the Tennessee side of the park we checked.
We did not check the North Carolina side of the Park. It has been much better
from a water level standpoint than the Tennessee side for the last month of so.
Why it has received more rain is a good question that we don't know the answer
to.
One of our main concerns is the effect of the drought on the aquatic insects. We
believe that this can be as bad or worse on the trout than the actual water
temperature. Generally, there is not a real problem with the lack of dissolved
oxygen until the temperature reaches the mid seventies for some time. That has
been the general guideline used in Yellowstone National Park for closing the
streams. If the water has remained in the mid seventies for any length of time,
they have usually closed it to fishing. It is doubtful this will ever be done in the
smokies and it is doubtful it will ever be necessary.
One big difference (other than the thermal influence of some streams) is the fact
that most of the streams in Yellowstone are directly exposed to the sun. In the
smoky mountains, most of the streams are shaded from the direct sunlight, a
fact that probably saves the fish when the air temperatures reach the high
nineties.
Getting back to the aquatic insect problem, it appears to us that as much as half
of the insect population could be destroyed by the drought. Many of the anglers
that fish the smokies apparently think the fish actually feed on hair and feathers,
but they don't. They feed on aquatic insects to a large extent. Some think there
are few aquatic insects but again, there are enough to sustain the life of the
trout that live in the park. If there were not, you would not have the fish you
have. The bottom line to this is that there are a lot more aquatic insects in the
park than most anglers think there are. This false line of thinking is largely due
to the fact that attractor flies work well much of the time (as with any freestone
headwater stream) and also to the fact that for some reason, the typical smoky
mountain angler is far less knowledgeable and/or aware of aquatic insects than
anglers from other parts of the country. It is obvious that most anglers that I
have talked to who place little emphasis on the aquatic insects, know very little
about them.
When the water gets as low as it is now, the millions of aquatic insects that live in
the stream have less substrate or bottom to live on. The clingers, some crawlers
and a few burrower mayflies are mostly effected. The few species of swimmers
are not as most likely not as affected. The smaller stoneflies (we would guess)
are effected along with a few cased caddisfly species. If they don't or can't move
as the water recesses, they will die.
We have no way of knowing just how many die and have been able to find only a
few studies (non locally) that have been done on this subject. Although we have
studied the insects in the park for the last two years extensively, we have not
done so from this standpoint. At this time of year, most of the aquatic insects are
less than half grown. It just seems to make common sense that many die from
the drought situation. If this is true, and we feel confident that it is, then there is
far less food for the trout - maybe as much as half of the food as there would
otherwise be. The brook trout, our only native fish of interest to the fly angler,
must be able to cope with this problem fairly well because it certainly is not a new
one for them. On the other hand, the non-native species of brown and rainbow
trout, are probably affected more so than the brook trout. We base this on the
fact that they are not suppose to be here anyway. We have no way of proving
any of this. We don't have any way of knowing just how abnormal the low water
situation is at this time. It is the second time this year it has been very low. We
feel certain the park fishery biologist keep records on this and that they are
aware of its affect on the trout. One thing for sure. It won't be very long before
we all will be able to see how everything turns out. One thing we will bet on, is
that the situation will be certain to provide a good excuse for many anglers.
The good news is that most likely, the problem won't last much longer. At least
we hope and pray it doesn't. This will most likely be our last report until
November. Until then we plan on seeing just what the drought condition has
done to the Yellowstone trout.
Copyright 2007 James Marsh