....................... ......Fly Fishing Yellowstone National Park
Fly Fishing Yellowstone - Adult Green Sedge
The adult Green Sedge (caddisfly) becomes important during the time the female caddisflies are depositing their eggs. The female dives down into the water and deposits her eggs on the bottom or the stream and underwater objects. She then returns to the surface where she either dies or dries her wings and flies away to return again at a another time. Some of you may not be aware that most caddisflies make more than one attempt to deposit their eggs. They may dive in the water a few times and then return to the bushes for a period of time before returning to the water to repeat the process. Even when they are finished and they die, they do so on or near the surface of the water. Trout have an opportunity to eat them either way.
Presentation: When it comes to getting the fly to the right place it matters little how you go about it as long as you don't spook the trout feeding on the egg layers. They will deposit their eggs in the same water they hatch from. This is usually pocket water of fast, flowing smooth water such as you find in may streams like the Yellowstone River below the lake or parts of the Madison and Firehole Rivers. These caddisflies are fast water species. They are not found in still or very slow moving water.
When you see the Green Sedges depositing their eggs, get your fly in the same area. The times of the day that they deposit their eggs will vary with the exact species and season. Basically, the later in the year or the warmer the weather and water, the later in the day they will deposit the eggs. When the water is still fairly cold, say below fifty-five degrees, they usually deposit them from the late afternoons until it gets dark. When the water is warm, it may not start until the evening and continue on into the night.
You can add some weight in front of the fly a few inches up the tippet and fish it like a wet fly, imitating the diving eggs layers, but we normally just fish it on the surface as a dry fly. At some point the egg layers return to the surface to die or fly away, so the trout are used to seeing them on the top of the water.
In some cases the caddisflies crawl down the rocks, boulders, deadfalls and plant stems to deposit their eggs. In those cases they accent to the surface when they are finished pasting their eggs. The fly works in either case. When they crawl down or dive down to the bottom.