Big Lost River Tailwater Fly Fishing Report & Options for Selecting Flies: Email us at (sales@perfectflystore.com) with the dates you will be fishing and we will send you a list of our fly recommendations. We can get flies and gear to you within two to three business days from the time you place your order via Priority Mail. If you provide a budget for flies, we will select them to match the budget and get them to you on time for your trip. Your can also call us at 800-594-4726 and we will help you decide what flies and gear to use. All orders are shipped free in the U.S. If under a $100 order requiring Priority mail is a charge of only $8.10. Orders over a $100 are shipped free via Priority Mail.
We have custom Perfect Fly selections in 3 different price ranges for this stream that come with or without fly boxes that make excellent gifts. Click Here To Order or Call us at 800 594 4726 or email us at sales@perfectflystore.com.
Type of Stream
Freestone Stream
Species
Rainbow Trout
Brown Trout
Cutthroat Trout
Brook Trout
Bull Trout
Golden Trout
(Wild and Stocked depending on the
area)
Location
Central Idaho
Size:
Small to Medium – 75 miles long
Nearest Towns
Ketchum
Season
Varies depending on the location
Access:
Good
Special Regulations
Yes, on the East Branch and Main
Stem
Non-Resident License
State of Idaho
Weather
National Weather Service Link
Stream Flow Data:
Real Time USGS Data (Arco)
Recommended Tackle & Gear
Fly Line:
4, 5 or 6 weight
Leaders:
Dry fly: 9 &12 ft., 5 or 6X, Nymphing:
71/2 ft., 3 or 4X, Streamers 0-2X
Tippets:
Dry fly: 5 or 6X, Nymphing: 3 or 4X,
Streamer 0-2X
Best Fly Rods:
Perfect Fly Supreme Four, Superb Five
or Ultimate Six
Fly Reels:
For 4/5/6 fly line
Fly Floatants and Misc Items:
Floatants, KISS Strike Indicators
Tools & Accessories:
Nippers, forceps, retractors, etc.
Copyright 2013 James Marsh
Fly Fishing the Big Lost River Tailwater Idaho: The Big Lost River Tailwater is located below MacKay Reservoir. The reservoir is a relatively small one with its water levels mostly controlled by the spring runoff and late summer agricultural irrigation needs. The tailwater is also small, averaging only about twenty to thirty feet wide.Its banks are lined with high grass and cottonwood trees as it flows towards the town of MacKay. The fishing is greatly influenced by the water releases. At times the water temperature can be high enough that it concentrates the trout in certain areas of the stream. It can also become crystal clear and require spring creek like techniques and presentations.During the spring when MacKay Reservoir fills up, the releases can be strong creating high water conditions that may not drop until the latter part of June. At that time the flows will become suitable for wading and fishing can be great.The wild rainbow trout are the highlight of the tailwater. They average between fourteen and twenty inches. They have been taken up to twenty-five inches. Although trout can be taken at times on dry flies, nymph fishing is the generally accepted method of fishing. Sight fishing to large rainbows with nymphs is a special technique used when the water is low and clear as gin.
Big Lost River Tailwater Fly Fishing Guide: As with many other tailwaters, the fishing methods and strategies depends greatly on the releases. This stream has some huge rainbows. The rainbows probably average between 15 and 18 inches. There are some hatches but not many. When there is a hatch, the dry fly fishing is usually great. Sight nymphing is popular during the winter.The dam releases greatly depends on the snow pack. In high snow pack years, the McKay Reservoir will stay full and the tailwater can remain high until well into the month of June and at times, almost the first of July. The ideal time to fish the river is when the water first drops down to a normal or low level. The ideal sight fishing flow is about 175 or less. Normal flows are about 540 early in the season and about 265 later in the season..This stream can become crystal clear. Catching the large rainbows in the clear water can become very difficult. Locals use 7X tippet and fish small nymphs during this time but it takes staying hidden and perfect presentations. The stream is relatively small with a lot of trees and bushes in the water. There are many overhanging bushes along the banks. One you hook a large rainbow in this river, you have usually just started the process of catching it. Landing it is a different thing.One of the most effective ways we have found to fish this river is with streamers. The large rainbows will smash a well presented streamer. This works best very early or very late. Many of the local anglers use a double nymph rig. These work best in the riffles and pocket water.There are several very meadows with lots of grass. Terrestrials will work during these late summer in these stretches. Midge fishing is also popular during the winter. The river gets some ice but the discharges and spring water that seeps in the stream keeps it mostly clear of ice all winter.If you are planning on fishing this river, always check the discharges and stream flows first. Everything depends on the water levels. They are generally high the first part of the season but drop through the summer and can become low during the Fall.
Big Lost River Tailwater Hatches and Trout Flies: Our information on aquatic insects is based on our stream samples of larvae and nymphs, not guess work. We base fly suggestions on imitating the most plentiful and most available insects and other foods at the particular time you are fishing. Unlike the generic fly shop trout flies, we have specific imitations of all the insects in the Beaverkill River and in all stages of life that are applicable to fishing. If you want to fish better, more realistic trout flies, have a much higher degree of success, give us a call. We not only will help you with selections, you will learn why, after trying Perfect Flies, 92% of the thousands of our customers will use nothing else. 1-800-594-4726.The hatches on this tailwater can be especially good. The water chemistry is suitable for a large variety of aquatic insects including the famous Salmonfly. During the winter, the hatches consist mostly of Blue-winged Olives. These hatches can occur from late November until near June. Several species of baetis exist in the river.Midges are the only other substantial hatches that occur during the winter months and imitations of their larva, pupa and adult stages of life can produce well at times. You can actually catch trout in the tailwater on midge imitations whenever you choose to fish. It’s just that they may be the only thing hatching on most winter days.Little Yellow Stonflies show up during late May and can hatch until late June. The Yellow Sallies can be an important insect to imitate during this time. Hatches are normally very consistent. The Salmonfly nymphs usually start moving to the banks to hatch during the middle of June. Hatches are normally over by the middle of July. Golden Stoneflies follow just behind the Salmonflies and also start appearing in June. They can last until near the end of July. Other than the BWOs, the bulk of the mayflies will be the Pale Morning Duns. They start hatching in June and last into the first of August. The Blue-winged Olives (baetis) mayflies will reappear during the month of August. Hatches of these little mayflies can last on into September. Caddisflies are the most consistent hatches of aquatic insects. Little Short-horned Sedges and Green Sedges (Rock Worms) hatch starting in May and last through June. Different species of Spotted Sedges start in early June and hatch until late September. They represent the most important caddisfly hatches. There are several more species of caddisflies in the tailwater but they are not usually heavy hatches.Terrestrial insects become important during the month of June. Imitations of ants, beetles and grasshoppers can produce until as late as the end of September. The huge amount of tall grass that line the banks provide the perfect habitat for the hoppers as well as the other land based insects.When the water is high, streamers can sometimes produce. Heavy weighted streamers like the Zonker can be used to hang some of the large rainbows at times.Specific imitations of the Little Yellow, Golden and Salmonfly stonefly nymphs are important flies to have. Imitations of the BWO and PMD nymphs are also effective for sight fishing during low, clear water conditions. Of course we recommend our “Perfect Flies” not just because they are the most realistic imitations but also because they are also the most productive flies you can purchase. Imitations of the stonefly nymphs have been proven to work on the Big Lost River tailwater.