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Armstrong Spring Creek Fly Fishing

Originating in the heart of Paradise Valley, from the Yellowstone aquifer, Armstrongs Spring Creek (sometimes referred to as O’Hair Spring Creek) is 8 miles south of Livingston, Montana. Outside of providing the Yellowstone River a flush of ice-cold water year-round, the spring creek provides essential spawning habitat for rainbow, brown and cutthroat trout.

The spring creek is roughly 4.1 miles long in total length, and the Armstrong portion of the stream offers 1.3 miles of fishable water. Further downstream is Depuy’s Spring Creek which requires a separate rod fee and reservation. The headwaters begin on the O’Hair property and gains a significant portion of its water from three individual springs. Several seeps on the creek bed provide additional water throughout the watershed, which grows the creek from averaging 20ft wide to up to 100ft wide at its widest point.

Spring creeks provide not only consistent flows but consistent water temperatures year around too. On average, Armstrong Spring Creek fluctuates 4 degrees throughout the year – 48-54 degrees Fahrenheit.

View All Montana Spring Creeks

Sections of Armstrong’s Spring creek

Upper Section
Arguably the least popular section of the creek, the upper stretches of Armstrongs tends to be the slowest in regards to fishing activity. Siltier than the rest of the stream, insect life is relatively low. This, of course, results in small and sporadic hatches and the least fish per mile throughout the entire creek. You will find some of the largest fish in the stream up here – presumably escaping the angling pressure from down low. Sight nymphing will be the name of the game here, typically, and using small midge larva patterns is highly recommended.

Middle Section
Hands down, the middle section of Armstrong’s is the most productive. With the most riffles, best insect life, and highest trout counts, most anglers will focus their efforts in this area. Of course, these fish see the most angling pressure and have seen just about every good and bad presentation. During the PMD hatch, the most popular riffle on the property, the “Diagonal Riffle,” seems to almost come alive with 100+ fish in it eating insects. It’s quite the sight!

Lower Section
Starting from the Diagonal Riffle to the Depuys property border is the lower section of Armstrong’s. Home to the largest fish on the creek but arguably the spookiest. Sight fishing is the name of the game, and the rewards can be great for putting in lots of time fishing this section.

This is also prime spawning habitat, and tread lightly if you plan to wade in this area. Brown trout spawn late in the spring creeks due to consistent water temps – you can find fish actively working redds even in winter. Rainbows and cutthroats will use this area in the spring as well for their yearly spawn.

Seasons on Amerstrong’s Spring Creek

Spring/Early Summer
As the air temp warms, quality hatches of spring BWO’s start in March and will last until May on most years. Fish are eager to sip duns off the surface and eat a well-presented dry fly with commitment. These fish have experienced minimal pressure for the last few months, producing some fantastic days on the creek. Relatively small, we suggest being prepared with baetis patterns in the 18-22 size range.

Typically in late April to early May, we see the yearly emergence of “Mothers Day Caddis.” This section of the creek generally is too cool for an actual large caddis hatch and gets the majority of its insects from the Yellowstone River. The fish will eat a well-presented caddis dry even when they aren’t the primary food source in the creek for them.

Once mid-June arrives, it’s PMD time. This is hands down the creme de la creme of spring creek fishing, and the reason anglers book rod spots up to two years in advance! These early-season PMD’s are large and easy pickings for hungry trout. Ranging in size from 14-18, there’s no mistaking when these “yellow sailboats” start appearing on the surface. These insects tend to bring every fish in the creek up and feeding – this showcases just how healthy the trout population is on this small water.  Later in the summer (mid-July), the stream will see the second species of PMD’s – ephemerella inermis. These duns range from size 16-20, and the fish know it. Be prepared to fish emergers and floating nymphs this time of year, as the trout have seen a large smattering of dry flies by now. Your fly box better be full of offerings as this is actual technical spring creek fishing.

The yearly grasshopper “hatch” begins in mid-July and provides the most prominent protein source of trout in the spring creek. Hope for a windy day, as this will help push these insects into the stream and turn them into an easy meal for the waiting trout. Beetles and ants are also insects high on a trouts list this time of year and can fool even the most selective of late-season, spring creek trout.

As another Montana summer draws to a close, fish begin to look for big calorie meals to pack on the weight before a long winter shows up. Twitching sculpins, woolly buggers, and other small streamer patterns will entice trout off the bottom or out of undercut banks for an easy meal. Nymphing the tail outs and soft runs will also prove effective with scuds, sowbugs, and many mayfly imitations.

With the consistent flows and water temps found on Armstrong’s, hatches follow suit in being consistent and decently predictable. During the winter months, midge hatches can be pretty prevalent and are an essential food source for these trout during the long Montana winter. If you catch it just right and have a calm and cloudy day in Paradise Valley, the midge fishing can be life-changing! Nymphing on Armstrongs during the winter months proves to be the most fruitful method. Scuds, sowbugs, midge larva, and small mayfly imitations are sure to pick up a trout or two in the deep pools.

While only 1.3 miles in length, Armstrong’s Spring Creek can offer a wide variety of fishing scenarios for anglers of all skills. An authentic year-round fishing experience can be had at Armstrong’s. Don’t forget to plan well in advance if you’re hoping to fish the famed PMD hatch, as dates will fill up one to two years in advance!

Armstrong’s Spring Creek Flies

Dry Flies

  • Captive Dun (size 14-20)
  • Sparkle Dun (size 14-20)
  • Last Chance Cripple (size 14-18)
  • CDC Biot Emerger (size 14-18)
  • X-Caddis (size 14-18)
  • Corn Fed Caddis (size 14-18)
  • Rusty Spinner (size 14-20)
  • Short Wing Emerger (size 14-20)
  • Griffith’s Gnat (size 18-22)
  • Film Critic (size 14-18)
  • Fur Ant (size 14-18)
  • Foam Beetle (size 12-18)
  • Dave’s Hopper (size 8-12)


  • Pheasant Tail (size 14-22)
  • Crack Back PMD Nymph (size 14-18)
  • Red Copper John (size 12-18)
  • Prince Nymph (size 14-18)
  • Zebra Midge (size 14-22)
  • Sparkle Scud (size 14-18)


  • Spring Creek Leech (size 6-10)
  • Black Sparkle Bugger (size 6-10)

Lodging Options

Yellowstone Valley LodgeYellowstone Valley Lodge – recently renovated and re-opened – is a highly personalized Montana fishing lodge located in beautiful Paradise Valley, Montana. Built directly on the banks of the world-famous Yellowstone River – known for its prolific hatches and excellent cutthroat and rainbow fishing – YVL offers the finest location in the entire area. Through head guide and outfitter Eric Adams, the Lodge is committed to offering the best Montana fly fishing experiences on the world-famous waters of the Yellowstone, Madison, and Boulder Rivers, as well as area spring creeks that include Armstrong’s, DePuy’s, and Nelson’s. From any of the ranch’s 16 private riverside cabins, you look directly over the Yellowstone River in the shadow of Dexter Point (elevation 9,859 feet). Notable additions to the Lodge include new and upgraded furnishings in the cabins, added availability for additional activities such as hiking, rafting, horseback riding, and coordinated transportation services to and from the airport in Bozeman.

Related Articles:
Quake Lake Fly Fishing

Nelson’s Spring Creek Fly Fishing
Depuy’s Spring Creek Fly Fishing


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