Island Park Reservoir
lake in Idaho
Island Park Reservoir offers a different fly fishing experience, with opportunities for targeting large trout from boats or float tubes, particularly around inlet and outlet areas, or during callibaetis hatches.
River flow last 30 days
What's working on Island Park Reservoir
- 01Trout are actively feeding on Mysis shrimp and leeches in deeper water.
- 02Chironomid pupa patterns are a consistent producer when fished under an indicator.
- 03Streamer patterns, like Woolly Buggers and Muddler Minnows, are effective for enticing larger, predatory trout.
- 04Keep an eye out for intermittent fall BWO and PMD hatches for dry fly opportunities, especially on cloudy afternoons.
- 05Egg patterns can be highly effective near any areas with spawning trout.
Past reports week by week
10 weeksWhat to tie on
Picked from reports, hatches and the season. Tap a fly for the recipe and where else it works.
PMD (Pale Morning Duns)
Fall Pale Morning Dun hatches can occur on reservoirs, providing opportunistic dry fly opportunities for rising trout.
Mysis Shrimp (Nymph)
Mysis shrimp are a consistent food source for trout in cold, clear reservoirs like Island Park, especially in the fall.
Blue-Winged Olive (BWO) Comparadun
Fall Blue-Winged Olive hatches are common, especially on overcast days, offering selective dry fly opportunities for trout feeding on emergers and adults.
Buy at AmazonWoolly Bugger (Olive)
A versatile streamer pattern, the olive Woolly Bugger imitates leeches and baitfish, which are consistent food sources for predatory trout in the fall.
Balanced Leech (Black)
Leeches are a year-round staple forage in stillwaters; aggressive trout will be actively feeding on them in the fall as they bulk up for winter.
Blood Dot Egg
Fall is spawning season for trout, making egg patterns highly effective for opportunistic fish keying on available eggs.
Buy at AmazonChironomid Pupa (Black)
Midges are a primary and consistent food source in stillwaters year-round. Fishing pupa patterns deep under an indicator is a reliable fall tactic.
Muddler Minnow (stillwater)
This streamer effectively imitates baitfish and sculpins, enticing larger predatory trout in lakes during the fall as they feed aggressively.
Where to fish and who to ask
Big Springs Inlet
The confluence of Big Springs Creek with the reservoir, a key area for foraging trout.
Butte Sinks Area
Extensive shallow areas with weed beds providing excellent habitat for trout and abundant insect life.
Island Park Dam Area
The area near the dam and the Henry's Fork outlet, often holding concentrated fish.
Fly shops within 40 miles
Henry's Fork Anglers
TroutHunter
Three Rivers Ranch Outfitters
Madison River Outfitters
Get Island Park Reservoir reports by email
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Idaho season by season
What changes on the water through the year, with the flies for each season.
Read before you go
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Quick answers
Common questions about Island Park Reservoir.
What flies work best on Island Park Reservoir?
Our top scored fly patterns for Island Park Reservoir right now are Callibaetis Nymph (80% confidence), Chironomid Pupa (80% confidence), Woolly Bugger (Olive) (80% confidence). These picks are scored from recent fishing reports, hatch data, and seasonal patterns.
What fish species are in Island Park Reservoir?
Island Park Reservoir holds Rainbow Trout, Brown Trout, Cutthroat Trout. See the species links on this page for fly recommendations and seasonal behavior for each.
What are current flow conditions on Island Park Reservoir?
Live USGS streamflow readings for Island Park Reservoir are charted in the sidebar of this page and updated automatically from the nearest gauge.
Is Island Park Reservoir fishing well right now?
We publish a fresh bite report for Island Park Reservoir each week based on recent on-the-water intel. The current report — with conditions, hatches, and what's producing — is on this page.