Insects and other foods the trout may be eating:
1.   Blue-winged Olives - mostly Little BWO - Isolated hatches
2.   Giant Black Stoneflies - hatching
3.   Cinnamon Caddis - Mostly Abrams Creek
4    Light Cahills - hatching
5.   Midges - hatching in isolated locations
6.   Little Short-horned Sedges - should hatch randomly for 2-3 months
7.   American March Browns - hatching but randomly in isolated locations
8.   Streamers - matching sculpin, baitfish and small crawfish
9.   Little Yellow Stoneflies - hatching
10. Green Sedges - hatching
11. Little Sister Caddisflies - Mostly Abrams Creek
12. Eastern Pale Evening Duns - (called Sulfurs by some)
13. Sulphurs - hatching in isolated areas
14. Golden Stonefly - hatching
15. Little Green Stonefly - hatching
16. Slate Drakes - hatching

Slate Drakes
The Slate Drakes belong to the Isonychia genus of the Siphlonuridae family of
mayflies. The most important species is the bicolor. It is a very common mayfly.
These mayflies are also called  “Dun Variant”, “Leadwing Coachmans” and
sometimes Mahogany Duns. The species name, bicolor, comes from its legs that
are bi-colored. The common name “leadwing” comes from the lead color of the flies’

This mayfly can hatch from spring until fall, but is very sporadic throughout that long
period of time and this makes it difficult to pin the exact times down. When they do
hatch, however, they can be prolific. I can say this for certain - there are a
tremendous number of nymphs of these mayflies in just about any stream in the
park you want to check.

The nymphs are swimmers. They remind me of larger minnows or baitfish. They can
actually dart around. They are not easy to catch. You cannot simply pick up a rock
from the streams bottom and see one. They will shoot away as soon as you touch
the water with your hand. You are not suppose to do that in the park anyway. To
make sure I get my disclaimer in, it is against the rules to disturb the rocks in the

My main point in mentioning that they are swimmers is to point out that they are
available for the trout to eat anytime they can be caught by them. The trout can and
do eat them year-round. An imitation of the Slate Drake nymph is a good fly to use

Hatching usually occurs late in the afternoon, and sometimes into the evenings, but
will occur occasionally during the day if it is cloudy or rainy.  These mayflies usually
crawl out of the water on the banks and on boulders and rocks to hatch. You will
find their shucks along the banks after a hatch. Some anglers claim that some of
them hatch in the water but we have never verified that. We do see a lot of shucks
where they hatched out of the water. I have picked up nymphs from rocks that were
half way emerged into a dun.

That is why an emerger fly pattern or a dun fly pattern is not necessary. The trout
would only see an emerger or dun if it were accidentally to get into the water. We do
not have a "Perfect Fly" pattern for either the dun or emerger, only the nymph and
spinner which are important from a fishing standpoint. Anytime you see a dun for
sale, you know automatically the person selling/tying it didn't have a clue what he or
she was doing.

Tomorrow I will get into the details of fishing the nymphs.

Copyright James Marsh 2009