Big sky anglers weekly fishing report – 7/8/2021

by | Jul 8, 2021 | 0 comments

This image has an empty alt attribute; its file name is newsletter-button_constant.png

The longest days of summer have us fishing and guiding every waking hour of the day. At night, some of us are tying flies and preparing for another day in the field. Boats are sprayed out and and coolers restocked. We are staring at materials on the bench and pouring a Jack & Coke to take the edge off. We wonder if that trout would’ve eaten a #16 Rusty Spinner or if it really was eating spent caddis. We sit in the back yard of the Golden Stone Inn with long time anglers who’ve helped us get where we are today all the while sharing stories from the past 20 years over a bottle of wine. We go to sleep with the sound of the water slapping against the boat and the squeak of the oar lock we forgot to grease. The day always ends and with it comes anticipation of what tomorrow brings. Light in the sky will show up at 5:15 am and with out a doubt there will be a trout, some where in Big Sky Country, rising until 10 pm. Get after it folks, Winter is never that far away.

Big Sky Anglers is OPEN from 7am to 9pm seven days a week. Our fly shop remains a clean and healthy environment for both our customers and staff members. Stop on by, say hello, and we’ll get you taken care of. Most importantly, stay safe, stay healthy, and enjoy your time outside.

Take care and fish on,
~ Joe, Justin, Jonathan, and the BSA Crew


Island Park Dam:   1480 cfs

Ashton Dam:   2580 cfs

St. Anthony:   1170cfs

Falls River at Chester: 139 cfs

More stable flows have been the groove this last week on the Henry’s Fork, there have been some fluctuations, but the overall flow has remained around 1400-1500 cfs.  Much of this is due to spotty, at times intense, rainfall throughout the Greater Yellowstone.  We expect rising flows soon, but every afternoon shower helps to keep things close to where they’re at for the time being.  Not to mention those Henry’s Fork mayflies like that sort of thing, too!

The Box Canyon running at a pushy 1480 cfs is holding up to its reputation as the workhorse of the river, providing lots of anglers with a great day’s fishing experience.  This is primarily a nymphing endeavor, but a keen eye and a persistent angler might find some trout willing to take a dry fly.  PMDs and goldens will provide most of the opportunity.  Rubberlegs nymphs 6-10, red and brown Zebra Midges 14-16, Perdigon nymphs, Pheasant Tails, and Caddis Pupa flies are all doing the trick in there.  I start with a single BB split shot at the top of the fast water for weight and adjust from there.

The Railroad Ranch section of the Fork is in what many anglers consider to be one of the best times of the season.  However, high flows affect hatches and trout behavior, so be prepared for a day to day assessment of what it takes to have success here.  Afternoon rain showers can be accompanied by thunder and lightning, but also by good mayfly hatches, keep clear of nature’s fireworks and be on the lookout for bugs.  Anglers should come equipped with spinners of various shades, surely rusty and yellow in 12-20, small olive caddis 16-18, tan caddis 16, PMD patterns in all phases:  transitional, emerger, cripple, dun, and spinner 14-16, as well as flav or BWO patterns in the same phases 12-14.  As ever, be on the lookout for any other opportunity that can come around, flying ants are on the list of possibilities and you won’t want to be without them if you come across them.  We like to always have a honey ant in a size 14 on hand as well as a small black winged ant in 16-18 sizes, the Shimazaki Ant is a good one to start with.

The canyon country below the Ranch is running high, but remains fishable with active trout for those looking for a wilderness experience with some good dry/dropper fishing.  A chubby Chernobyl with a rubberlegs or perdigon 12-14 under it is a staple rig in here.  Streamers play well during those afternoon cloudy periods, lots of flavors and colors to try here, but I usually start with a heavy olive and black fly like the BFE (Best Fly Ever).  We are now tying these with tungsten eyes for use in YNP, but they are proving deadly in Henry’s Fork canyon country.

The river from Warm River to Ashton is providing anglers with a solid day of action on dry/dropper and indicator nymph rigs.  The fish are generally 8-12” in here but there are usually a few chances each day at larger ones.  This is a great float for beginning anglers or for those who would like to have a few more chances at hookups than they’re finding elsewhere.

Below Ashton Reservoir, the river remains high, keeping the trout there healthy and happy.  Hatches and insects are sparse, but there are some great trout to be found down here for those willing and wishing to hunt them.  Please keep an eye on water temperatures down here, when it hits 70 degrees in these sections, it’s usually time to hang it up.  Be on the lookout for spinners 14-18, sparse PMDs and BWOs, golden stones, and hoppers. 

Get out there and have fun!


Yellowstone is seeing some terrific fishing, and beautiful weather throughout the high country these days. 

Warmer than average weather continues to be in the forecast this week. So, the high elevation fisheries in the park are a great option. 

As always, keep a close eye on the forecast and flows as afternoon/evening thunderstorms can bump flows and muddy waters in some of our favorite fisheries in the Park. Follow the links at the bottom of the report to check flows, or better yet, give us a call or swing by the shop in West for up to the minute info. 

We’re still in the heart of the busy tourist season. There is seemingly no shortage of people looking to experience the wonders of Yellowstone, and we can’t blame them – it’s spectacular! So, if you’re on a mission to get somewhere with a fly rod, be sure to leave as early as you can, pack a cooler, load a good playlist on your phone, and go with the flow. 

The Northeast Corner (Slough, Lamar, and Soda Butte)

The Yellowstone Cutthroat Triumvirate is in great shape and fishing very well. There was a slight blip one day this past week on Soda Butte Cr, and the Lamar R with some green water due to an evening thunderstorm the previous day, but conditions quickly improved and are now good to go. 

This area requires special attention to flows and weather. As the “old timers” (those over 40) say, “a bison could relieve itself in the headwaters of the Lamar, and it will blow out!” So, suffice it to say, it doesn’t take much of a rain event to spoil your plans. Make sure you know before you go!

Gallatin River (in YNP)

What a fun time to be fishing the park stretch of the Gallatin River! Salmonflies, golden stones, pmd’s, caddis, flavs, and the last of the Green Drakes will keep you occupied for most of the afternoon and evening hours. 

When fish aren’t looking up, a small tungsten nymph fished below a dry fly or on a tight line is a great way to prospect. 

Along with a tremendous diversity of bug life, the Gallatin River in YNP has a great variety of fish in it’s waters. You can expect to see Rainbows, Browns, Cutts, Whitefish, and occasionally, a Brookie. 

gardner River

The Gardner River, The Gallatin’s sister river to the East, is also in great shape and a fun option these days. PMD’s, Caddis, and Stoneflies are active, but the Gardner is a great river to prospect with small attractor dry flies.

If you enjoy fishing with a long rod (10-11 feet), this is a perfect place to high stick with a floating line, a big, fluffy dry fly and a light, 2 or 3 wt rod. If you’re new to fishing with the longer, lighter (Euro-style) rods, this is a great way to get comfortable with line handling, rod position, and movement through the drift. 

Yellowstone River

The Holy Grail of Cutthroat Trout fishing opens for the season on July 15. This iconic section from Chittenden Bridge upstream towards Yellowstone lake is not only a bug factory, but also a sanctuary for the rebounding population of Yellowstone Cutthroat Trout. Population numbers have been on a steady increase for several years, and we are excited to get back up into the caldera to see for ourselves how things are looking for the 2021 season. 

Flows leaving Yellowstone Lake continue to drop slowly, as they naturally do every year, and we expect the river to be at a great, fishable level for the opener. 

While we anxiously wait to fish the upper river next week, the lower canyon stretches of the Yellowstone offer an adventurous option for anyone looking to hike into some remote backcountry waters. Never venture into canyon country lightly, as this is rugged terrain with lots of elevation gains and losses required to access the fishing. Naturally, you will need to be well heeled with bear spray, plenty of water – or better yet, a water filter -, and a well appointed backcountry pack with a raincoat, extra layer, and first aid kit. If you need help putting together your backcountry kit, swing by the shop and we can help get you dialed in. 

MADISON RIVER – BY Joe Moore & Marshall Fairbanks

There were two bumps this week and flows out of Hebgen Dam are clipping right along. We are sitting at 1260 CFS up top and 1620 at Varney Bridge. These flows are ideal and we couldn’t be more ecstatic. River temps are fluctuating about ten degrees throughout the day and the fishing is hanging right in there.

Wade Stretch: Big bugs are still fluttering about but the best of those days are now behind us. PMDs and Caddis are where it’s at; these flows are a blessing and should allow us for some high quality bank fishing. An observant eye will be your best asset, watch the river as it will give up the secrets if you pay enough attention. Nymphing with rubber legs, BH pheasant tails, golden stone nymphs, perdigons, prince nymphs, and crystal dips has been effective in the deeper runs. Find a caddis pattern you believe in, cover water and fish the skinny, sexy, nervous waters.

Float Stretch: Now is the time to run long floats. Lyons to Ruby, Windy to Story or Ruby to Varney are all solid choices. Fish are eating mid river and those gravel bars are flush with water. Drop a tungsten bead head off that Chubby and roll it. Caddis have been the main dry fly in the float stretch, but there are mayfly spinners throughout the river. Micro Chubbys will take their fair share if trout as well and if you find yourself wondering what else to toss out there, ants are always a solid choice as we enter mid summer. If you haven’t fished Jojos’ Royal Ant, you should be. PMD’s have been on the water and look for them on the cloudier, cooler days. Nymphing from the boat is a great option as well with fish eating Hare’s ears, PT’s, Shop Vacs, various Perdigons.

Please be respectful to those fish that do eat your fly. Land them quickly and take care to revive each fish with your anchor on the bank. Trout pics are something we all enjoy, but if you can avoid it in the afternoons please do so. Get creative with your pics and keep those fish wet. Celebrate those trout in the net and enjoy just watching them swim away,


With the warm weather, we are starting to see the beginnings of significant callibaetis hatches on our area lakes. Gulper time is right around the corner. If you are seeking callibaetis activity to drive your angling, remember that they are a very weed-oriented insect. Right now, the hatch will be strongest in sections of lakes with warmer, weedy shallows. In many of these areas, chironomids will also be competing for the fish’s attention, so be prepared to fish both tactics during your sessions. This is the time of year where trout may be keyed in on one or the other depending on the level of bug activity, and it may actually switch from one to another throughout the morning into midday.

For those looking to up their callibaetis game, navigate over to our blog and check out our posts about this high profile stilwater insect.



Below are links to the flows in Montana and Idaho as well as. This time of the year flows and the weather are changing daily, if not by the hour. Click the links below for the most up to date information.

Montana River Flows
Idaho River Flows
West Yellowstone Weather Forecast