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Fishing ForecastFishing Report

August Approaches

By July 26, 2010April 14th, 2018No Comments


As July nears its end, it is interesting to look back at the fluctuating river conditions local anglers have seen this month. The flows on the Salmon River, the upper Big Lost and the Big Wood during the latter part of June and early July were near record setting. It seemed as if the high water would never subside despite the fact that we had a below average winter snowpack. As predicted by many, once the rivers finally began to lower, they did so quickly. As the levels subsided, our local rivers produced world-class angling; however, this wonderful window of angling is drawing to an end. Fortunately, our local spring creek is becoming very active in the mornings and our alpine streams are starting to be excellent fish producers. Good fishing can be found on all our local waters in the mornings and evenings as the heat of the day drives some of the larger, better educated fish toward their deep water, mid-summertime hangouts.

Silver Creek

The Creek has turned on noticeably in the mornings with Baetis being the main attraction in conjunction with PMDs and the burgeoning Trico spinner falls. Downstream presentations are a must and 6X tippet on 12-15 feet leaders should be the standard tackle selection. Baetis and Tricos (sizes 20-22) will be the best picks for the fly box, but make sure to come equipped with dun, emerger, cripple and spinner patterns. Begin the morning activity throwing dun patterns as the earliest spinners will present as healthy adults until later in the morning when they give up the ghost and drop their wings to the water’s surface. PMDs will be mixed in mid-morning and trout will key in on them briefly during the morning’s madness. Remember, it is important to change patterns often as these wily fish tend to identify imitations quickly making for refusals sometimes after only 2 or 3 presentations. Rotating through a half dozen Trico and occasionally casting a Baetis and PMD will keep the fish guessing, off-guard and on the end of your tippet. In the afternoon when the minute mayflies have subsided, try floating damselflies and Grasshoppers near weed beds and under-cut banks. Callibaetis will also be present in the stillwater sections. Try size 14-16 speckled wing duns as well as size 16 Beadhead Flashback Pheasant Tails sight-nymphed to cruising fish or cast and stripped in the wind chop.

Big Wood River

At the end of last week, the Big Wood had dropped markedly, but the river has actually dropped another 50% in just the past few days! Although afternoon fishing can still be productive with Pink Alberts (size 16), Parachute Adams (size 12-16), Yellow Sallies (size 14), Elk Hair Caddis (size 12-16), Goddard’s Caddis (size 14-16) and PMDs (size 16), look to the mornings and evenings for the most productive fishing. Caddis and PMDs have a strong presence during these lower-light periods and can be dead drifted or skated as the evenings grow dim. Look to begin throwing Grasshoppers as well as they have been spotted recently on our local waterways.

Big Lost River

Although the water level below the dam has been raised again and wading this tailwater has returned to a dangerous level (602 cfs), some anglers have adventured into the spring creek flows above the reservoir, finding some success. PMDs, Baetis and soon, Tricos, will be present on this river although most fishermen are throwing large nymphs such as Princes (size 12-16), Flashback Pheasant Tails (size 12-16) and King Princes (size 12-16). Craneflies skated at a quartering down angle to the current can also bring large ‘Bows to the surface as they chase these sizable but highly mobile meals.

Upper Big Lost

The North, East and West Forks of the Big Lost are fishing very well. Cream Caddis (size14-16) are numerous in the evenings and mornings as are March Browns (size 14). Look for Yellow Sallies (size 14-16) to be the main attraction in the middle of the day in addition to PMDs (size 16). A variety of attractor patterns will work well right now in addition to the grasshoppers which are increasing in number and size with every passing day. Do be aware that some of the Finespot Cutthroats are still spawning in higher elevations and their redds should be avoided.

South Fork of the Boise

Driftboating has been the main attraction on the South Fork of the Boise as its summer flow makes walking and wading difficult. Large foam-bodied patterns are still turning fish although this will begin to diminish as the Salmonflies and Cicadas become distant memories. Choose cream and gray Elk Hair and Goddard’s Caddis (size14-16) in the evenings while throwing Pink Alberts (size 16) in the afternoons.

Salmon River

The Salmon is more temperamental now than the last 2 weeks as the heat of the summer and the lowered riverflow have pushed the best fishing to the mornings and evenings. Caddis are flocking to this freestone in massive numbers as the sun drops in the sky. Elk Hair Caddis in cream and beige (size 14-16) will take fish both dead drifted and skated. Look for continued PMD (size 16) presence in the late morning and significant Yellow Sally numbers (size 14) in the middle of the day through late afternoon. Black/red Flying Ants (size14) have also shown excellent numbers in the mornings while most of the larger Stoneflies have dwindled in population. Caddis, stimulators and grasshoppers can be used to drop large mayfly nymphs, stonefly nymphs and caddis pupae in front of fish hanging low in the water column as the daytime temperatures rise.

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