....................... ......Fly Fishing Yellowstone National Park
Fly Fishing Yellowstone - Spotted Sedge
Looks like Yellowstone is in for some lousy weather for a few days. Rain and snow is in the forecast until next Tuesday. Temperatures should be in the forties for the highs and twenties to thirties during the evenings. This will keep the runoff at a creeping pace.
The other caddisfly that is and will be hatching for quite sometimes now on the Firehole River, Lower Gibbons and Madison Rivers is the Spotted Sedge of Hydrosyphe species. These caddisflies will be around for some time. They are supposed to be the most plentiful caddisfly in the park but in the Firehole and Madison Rivers, that is challenged this day in time by the White Millers I just wrote about. They have increased in quantities for the past few years.
The spotted sedges are net-spinners. They don't build cases and that means they are available for the trout to eat as larvae. They build a shelter type covering that reside in but they hang out on the end of a silk string they produce when they feed. They form tiny nets that catch their food by filtering it from the water. These caddisflies exist in huge quantities and I suspect far more of them are eaten as larvae and pupae than adults although trout definitely eat the adult egg layers.
If you pick up a rock from the stream to look for these larvae, the net will collapse and be very difficult to observe If all other conditions are present, the more algae there are in a stream, the more likely there are net spinning caddisflies present. The Firehole River and Madison Rivers have a huge amount of algae.
There are about seventy species in the Hydropsyche genus. Fortunately, there is not much difference in the many species or certainly not enough difference that the methods of imitating them or the imitation itself (fly) needs to be different for the various species.
Every stream in Yellowstone contains Spotted Sedges. Some of them have huge populations of these insects. They live in the riffles and runs of the streams. They must have current to survive.