The World Famous Deschutes Salmonfly Hatch
The water conditions on the Deschutes River for the salmonfly hatch are
going to be a perfect this year with slightly lower than normal water flows. The river is slightly off-color and the flow is 3,640 cfs at Warm Springs and 4,450 cfs at Moody. The water levels have been fairly stable. This
situation was unusual in the 1980's when I started guiding on the Deschutes. The whole lower
100-miles of the river will have salmonflies and golden stones. To make matters even more unpredictable, this last winter was colder and wetter than usual. This makes the emergence pretty unpredictable as well.
The salmonfly hatch on Oregon's Deschutes used to be a May/June affair. Since 2012, Portland General Electric has changed the water flow
regime in the hydro electric facilities at Pelton Dam. This warmed the
river a few degrees during the winter, and moved the hatch ahead at
least two, possibly three weeks. Now the hatch is much shorter and the big bugs have been gone before June. Hatches have been sparser too. With the influence of the dam vs. an unusually cold and dreary winter, the hatch in 2017 will undoubtedly be a little later
than it has been the last couple of years, but probably not as late as the good old days. Don't worry, there will still be a salmonfly hatch and it will still be productive and exciting.
The actual hatch occurs on land or vegetation along the river. In order to crawl from the water, stonefly nymphs move toward the margins of the river in a mass exodus. It is during this migration that they are most exposed to feeding trout, and that is when fishing with nymphs is best for anglers. Certain river bed terrain, and current flows give the best advantage for leaving the river. Look for areas where nymphal shucks are prolific on the shoreline and fish the areas around them. Trout become familiar with the habits of the nymphs and move to areas where they can intercept them.
Adult salmonflies congregate in the vegetation along the shoreline where there is protection from the hot sun, which can quickly dehydrate them. Tall grass next to the water, and shady trees with branches overhanging the water become prime real estate for adult salmonflies and golden stones. Adult stoneflies aren't very active at night, and cool weather slows them down. Their activity really picks up when sunlight warms the air in the morning. This activity slows as the day becomes hot, and then increases again as the air cools toward evening. The trick is to fish where and when the insects are most active, and to be relaxed and observant the rest of the day. Cool, cloudy, or rainy days slow the stonefly action dramatically, and it is often better during cool periods to concentrate on other hatches.
When fishing hatches of large stoneflies, being able to target areas under low hanging tree branches and vegetated shorelines is critical to success. For this work, a six weight rod is better than lighter weight rods for turning over flies that are large and wind resistant. Windy days are often to your advantage if you can handle them. Wind blows a lot of insects into the water and the trout become more active too. Casting in the wind is easiest with short leaders, such as 7 1/2' 3X. You will lose fewer trout and fewer flies with this kind of gear. Remember, the salmonfly hatch brings the largest trout to the surface.
Stone and Salmon Flies