Henry’s Fork, May 23rd, 2023

Big stonefly nymphs are migrating in the river from Cardiac Canyon on downstream, but if any are flying and egg laying, their numbers are small enough that trout are not yet attracted. Aquatic insect activity is several days behind across the entire Henry’s Fork drainage. Here is an item from Rob Van Kirk’s SWE report filed yesterday concerning aquatic insect activity in the drainage: “Timing of aquatic insect hatches is running around 2-6 days later than average in the upper watershed and 4-11 days later than average in the lower watershed. Given continued snow melt, increased cloudiness, cooler temperatures, and rain, I do not expect hatch timing to catch up to average any time soon.”

Back country road and campground openings are also behind for this time of the season. With Memorial Day weekend coming up, the Ashton/ Island Park Ranger District office will have the best information on road and campground openings/closures.