Fishing Reports

Henry’s Fork, May 18th, 2024

Big Time Trout Food

The stone fly hatch on the lower river is beginning right on time. From Ashton Dam down to the Chester Dam nymphs are crawling onto banks. It will take some warm weather to advance the hatch in numbers, molting to adults, and to fly over the river. So until warm weather arrives, big nymph patterns simulating these insects will be among the most effective to use as resident trout key on such patterns. During this week the hatch should advance, and we will provide information on best locations to enjoy it into Memorial Day weekend.

By any measure the big stone fly appearance ends the so called shoulder season on the river. From now on high interest applies to the season long advance of insect life which makes fishing the river so famous. We at Fly Fish Food-Jimmy’s will monitor this advance on the river and provide solid information on it throughout the season.

Water Quality Statement from Dr. Rob Van Kirk’s SWE Report for the Henry’s Fork Drainage Filed Yesterday, May 17th.

Water quality continues to be good throughout the watershed. Water temperatures and dissolved oxygen concentrations are good to excellent and near average for this time of year. Turbidity continues to drop in the Warm River to Ashton reach and is also starting to drop downstream of Fall River. I do not expect abnormally high turbidity anywhere in the watershed for at least a week. Hatch timing is within a day of average at all locations and is likely to stay very near average for the next few days. Cooler weather next week could slow things down a bit then, but I expect average timing for the salmonfly hatch watershed-wide. Salmon fly adults have just started emerging in the spring-fed locations such as Buffalo River and Warm River, indicating just a few more days before they begin to hatch in large numbers in the reach between Ashton Dam and Chester Dam.

Henry’s Fork, May 11th, 2024

The Henry’s Fork continues to offer the most consistent fishing of any area stream. Good caddis, BWO, and midge activities are reasons for great top water fishing not only on the lower river, but on the river above. Here the Last Chance area and above Coffee Pot rapids are good areas to try. For streamer and nymphing enthusiasts, Box Canyon is worth a try using streamers and fly rod jigs.

Here is some encouraging water quality information from Dr. Rob Van Kirk’s Henry’s Fork drainage SWE report filed yesterday.

Water Quality

As good as water quality was on Wednesday, it was even better yesterday. Water temperatures warmed just a hair, putting them within the optimal range for development of rainbow trout eggs and fry in all river reaches. Increased sunlight yesterday resulted in higher photosynthesis than we have seen in a week, increasing dissolved oxygen watershed-wide. Turbidity continued to drop yesterday, although that trend will be reversed today as snow begins to melt. I expect the highest increases in turbidity to occur downstream of Robinson Creek and Fall River, which are the two tributaries that will respond the most to mid-elevation snowmelt over the next week. Hatch timing is a day behind average at most locations after slowing down over the past five days. However, I expect aquatic insect development to accelerate a little as temperatures warm, putting it back at average to a day or so ahead of average by the end of next week. That means upcoming springtime hatches—including salmonflies and March Brown mayflies—should be right on time.