Fishing Reports

Henry’s Lake, May 4th , 2024

Ice is retreating from the lake. The best time for early season fishing is when and where the ice is not far out from the shoreline. Leech and streamer patterns are good choices for action.

A request to help determine Henry’s Lake fish population and physical condition is below.

From Idaho Fish & Game – The ice is coming off the lake fast, and with that comes the beginning of our annual gillnet survey.

 When: We need help for the next two weeks. Looks like we need two volunteers a day to meet us at the Henry’s Lake Hatchery at 8:00 AM each morning. We can provide a truck and carpool up to the lake.

Description:  : The gill net operation will consist of picking fish out of the nets, count fish species, and collect any samples the biologist needs. The picking is the time consuming and can be the smelly part.

What to Bring: Please bring waders(if you have them), a rain jacket & pants(works best). The nets are wet, so waterproof clothing, or ‘work clothes’ is a must and layers to be comfortable in temperatures ranging from 25-70 degrees. Gill net catch rates vary, so working up nets can potentially take several hours and I would suggest packing Snacks, lunch and drinks.  

 Physical Demands: Weather can vary in Island park . Not a real physically demanding job but there is some bending/stooping/kneeling  and hand dexterity to remove fish from nets.

Please click the link to see what days are available. Then email me dates and contact information so I can add you to the schedule.  

Gerren B. Steel

Volunteer Services Coordinator

Idaho Department of Fish & Game

Work: 208-535-8039

Cell: 208-850-7576

Henry’s Fork, May 4th, 2024

Flow is down throughout the river thanks to our recent surprise snow storm (maybe more to come next week), So note what Dr Rob Van Kirk says below about development of aquatic insect growth in his water quality discussion below.. Nevertheless the lower river continues to offer the best stream fishing in the area with great BWO, mother’s day caddis, and midge activity bringing trout up from the bottom. If water quality stays decent and warms a bit, stonefly nymphs will soon wake up. All boat launch locations on the lower river are open.

Headlines from Dr. Rob Van Kirk’s SWE Report for the Henry’s Fork Drainage Filed Yesterday, May 4th

• Another cool, showery day kept water-year total precipitation at average and kept SWE constant at 83% of this season’s peak, compared with 87% of peak on average.
• Very cold, wet weather is expected Sunday–Wednesday, which will add snowpack and likely put SWE near average for the date by the middle of next week.
• Natural flow dropped for the fourth consecutive day and was 83% of average yesterday.
• Water temperatures increased a little yesterday but were still below average, continuing to slow aquatic organism development.

Water Quality 5/3/ 24

Water quality remains very good in all river reaches, as dissolved oxygen concentrations are high and turbidity continues to drop after last week’s peak streamflows. Water temperatures were a hair warmer yesterday than on Wednesday but still below average. Yesterday’s temperatures were generally below the optimal range for development of rainbow trout eggs and fry, which is not harmful but just slows development. Similarly, aquatic insect development continues to slow, as I had predicted at the end of last week. Current hatch timing is within a day of average at most locations but will drop to a day or two behind average by the middle of next week.

In absence of a managed freshet flow out of Island Park Reservoir, sediment mobilization and transport out of the Island Park-to-Pinehaven reach has been below average so far this spring, despite streamflow last week that was almost as high as last year’s managed freshet. In fact, yesterday’s net export of sediment from the reach was the lowest for the date in the 8 years we have measured that quantity carefully. There are two primary reasons for that: 1) there is relatively little fine sediment in that reach to transport this year after last year’s highly successful springtime freshet and subsequent low export of sediment out of the reservoir last summer, and 2) as we learned from last year’s freshet compared with previous freshets, rapid increase in outflow mobilized much more sediment than gradual increase, even if the magnitude ended up about the same. I expect relatively low sediment export rates to continue throughout the remainder of the period before aquatic vegetation growth really gets underway.

Rob Van Kirk, Ph.D.

Senior Scientist

Henry’s Fork Foundation

P.O. Box 550

Ashton, ID 83420

208-881-3407 CELL

Henry’s Fork, April 27th, 2024

The lower river offers the most consistent and likely the best fly fishing in the region. Mother’s Day caddis, BWO and midge activities are resulting in excellent top water fishing. Days with little wind are best. Streamer fishing also continues to be good during low light conditions. On the upper river the Last Chance area features some good midge hatches with a few BWOs showing, but weather can be difficult. Flow in the river is increasing as the run-off season is getting underway. The biggest impact will be on the river below the Fall River confluence downstream to the South Fork confluence.

Headlines 4/26

Water Quality information from Dr. Rob Van Kirk’s Snow Water Equivalent Report for the Henry’s Fork Drainage Filed Yesterday

Water quality remains very good in all river reaches and continues to show influence from rapid snowmelt watershed-wide. Conductivity continues to drop at all locations, indicating a large influx of relatively pure surface water from snowmelt. Turbidity continued to drop from a peak earlier in the week at Flat Rock but is still increasing at all other locations due to increased streamflow. However, current turbidity values are within the range typically observed during periods of snowmelt. Water temperatures were a little cooler yesterday than they were earlier in the week, and aquatic insect development is within two days of average at all locations. I expect hatches to slow a little over the next few days, as cloudy and cooler weather keeps water temperatures a little below average.

Rob Van Kirk, Ph.D.

Senior Scientist

Henry’s Fork Foundation

P.O. Box 550

Ashton, ID 83420

208-881-3407 CELL