....................... ......Fly Fishing Yellowstone National Park
Fly Fishing Yellowstone - Madison and Firehole Rivers - PMD Hatch
The Madison and Firehole Rivers both have some Pale Morning Duns hatching around the middle of the day. As I said yesterday, fishing the PMD hatch isn't just a matter of tying on an imitation of the dun and tossing it out on the river. At this time of the year, depending on the water temperature, the trout may not take the duns on the surface as well as they will the emerging nymphs. Another problem is that the water temperatures will vary depending where you are on the Madison River or the Firehole River. Actually, on the Firehole River, it will depend on exactly where you are on the river. The geysers change the water temperature at different locations.
To help make this simple, if you see the PMDs hatching (see the duns on the water) and the trout are not taking your dun imitation, change to an emerger pattern. Our "Perfect Fly" company makes two versions. One is more like the nymph than it is the dun and the other one is more like the dun than it is a nymph. It has a trailing shuck. If you are using our flies, and we hope you do, then start out with the emerger. If it doesn't work within a few minutes during the hatch, change to the trailing shuck version. Both flies float down in the surface skim. At times, especially if the water is on the cold side, the trout will not take the duns. If they do, then I am sure you would want to fish the dry fly or dun. I know I would.
As mentioned before, the PMD hatch will last much longer if the sky is cloudy or overcast. Even then, the hatch will not last all day long. It will only last for a couple of hours or maybe a little longer. My point is that getting on the water in the right place at the right time is very important. Otherwise, you won't be fishing a PMD hatch in either river, the Madison or the Firehole.
The little PMDs won't be hatching in the fast water of the riffles and runs. They will hatch in the smooth water. In the smooth water, they won't hatch any and everywhere. They will move from the fast water, smooth or not, to the slower water areas. This includes slow current seams, pockets behind rocks, underwater grass beds or where ever the water slows down. These are crawler nymphs, not clingers that live in the fast water. The best way is to observe the water carefully. Pay attention and the bugs will show you where to fish.