Guest Blogger: Mike Cline, Bozeman, Montana

What goes up must come down! Like clockwork, the June cycles of the Firehole River in Yellowstone provide for a challenging angling experience. A light work schedule (thankfully nothing since late March) allowed me to string a series of seven day-trips between May 28 and June 12 to the Firehole during the opening salvo of the 2018 Yellowstone National Park season. Each year, the park season opens on the Saturday of Memorial Day weekend. Despite having outstanding fisheries throughout the park, it is rare that any water other than the Firehole is fishable on the opener. It always attracts a lot of anglers, especially those that can make the easy trip from Utah, Idaho, Colorado and Montana for the weekend. However, by Monday, Memorial Day itself, the initial pressure subsides quite a bit. That’s when I make my first foray to the Firehole, always hoping for decent, fishable conditions.

We had a big snow year in Montana and a warmer than normal May had the big rivers in runoff early. That first trip of the season to the Firehole was always fraught with the odds that the river would be swollen and unfishable (if not just very difficult to fish). One of the big draws to the Firehole is the dry fly fishing (not my gig, but a lot of anglers live for it). Unfortunately, early season hatches can be sporadic if not absent completely if the river is cold and high. But that does not mean there isn’t decent fishing (catching I mean) if you get to the river at the right time in the right places.

In June, day trips to the Firehole begin with a 3AM wake up for the 120-mile trip. The car is loaded the night before so after the quick brew of a cup of coffee, I am generally out of the house by 3:15AM. A stop for gas before leaving Bozeman gets me on my way. The trip is not without its tension. The lower Gallatin canyon is a dark, winding road, with limited to non-existent passing. With dueling high beams and the occasional timid driver that shaves 20 miles off the 60-mph speed limit while tapping the breaks at every curve, the first hour of the two-hour trip can be frustrating. The village of Big Sky is reached around 4PM where the road straightens a bit and higher speeds and passing is easier. However, once you pass through Big Sky, the potential for encountering large quadrupeds crossing or standing motionless in the roadway increases. Inevitably, every trip requires at least one hard braking event to avoid hitting a large mammal, be it elk, deer, bear or coyote. If I survive the last hour of the trip, I reach West Yellowstone around 5AM. It is deserted, nothing is open—heaven—and the left turn into the park is a welcome milestone.

In June, dawn’s early light is silhouetting the Mount Holmes and the Gallatin Range to the north. Fog shrouds the Madison. There is no one manning the west entrance station and no traffic inside the park. Typically, at 5AM it is rare to see more than of couple of vehicles on the way to the Firehole. Once I reach the Firehole, it is easy to assess the conditions—high, normal or low. Typically, in early June it is high, but with a unique attribute that makes it an outstanding early park fishery for those willing to challenge it—water clarity. The Firehole never gets dirty so to speak always maintaining at least two feet of visibility in tea colored water. This clarity ensures that no matter how high the river might be, the fish have a good shot at a well-placed fly. This gets us to the real point of this post—the ups and downs of the Firehole and what it means for early season angling success. Although I fished several of my favorite spots during my seven trips, I really concentrated on my number one favorite section—Biscuit Basin meadow. In those seven trips, Biscuit Basin showed off the full extent of early season conditions one might expect from the ups and downs of the Firehole.

If you look at the flow and temperature regime for the nearest USGS gauge to Biscuit Basin in the images during the period May 27 – June 12, 2018 you’ll get a good sense of the oscillations this river experiences in the early part of the season. The primary reason for these oscillations in flow and temperature relate to the nature of the Firehole watershed. Most of the river sits at around 7000 feet MSL. The highest portions of its watershed rarely exceed 8000 feet MSL. In June, nighttime temps can fall well below freezing while daytime temps can reach 70 degrees. Warm days cause snow fields on the Madison Plateau to shed water which peaks in the main section of the Firehole by early morning, generally the highest flows and lowest temperatures of the day. Cold nights stems snow melt which causes flows to decline as the day progresses. As flows and clarity improve, the dark waters and dark bottom of the river cause temps to rise dramatically. In June, the river you fish at dawn is a different river by noon or later in the day. A cold day and cold nights in succession cause a steep decline in flows.

In Biscuit Basin meadow, there is a lot of deep water (3-6 feet at normal flows) as the river is braided with narrow sections and islands. At peak flows these sections are often bank full or more. Throughout the meadow, especially on outside bends, there are deep undercuts. There are also some massive bedrock ledges in these deep sections. All exceptional holding water for big fish but nearly invisible during high water. And in my book, Biscuit Basin in the low light of early morning hours is the place to go for a chance at a big Firehole brown or rainbow, especially in the first weeks of the season when the river is cool.

The high, tea colored water is a challenge for most anglers and more likely or not, sections like Biscuit Basin are usually deserted in the mornings during the opening weeks of the season. Getting three to four hours of uninterrupted, lonely fishing on a world-class river with the opportunity to nab big fish is a real treat that I look forward to every year. This year I tackled the challenge of the Rise and Fall of the Firehole with a new fly on an old theme. (The new fly, the Firehole Demon, will be J. Stockard’s Fly of the Month for July and it will be explained in Part II of this post to come later this week).


  1. Thumbs up (both). I envy you the quick? access to all that. We have to come all the way from Florida. We just happened to luck out this spring on the Bitterroot, and caught it just right before the melt down and flooding.
    Thanks for the great account!
    The old “Noslimeslinger”.

  2. I enjoyed the article Mike. I remember trying to track similar data for the Merced a year or two ago. There were multiple problems associated with using such gauge data effectively, among them that the gauges weren’t necessarily anywhere near where I intended to fish, that they didn’t really tell anything about wadable depth or current strength (which meant I really had to have gone through some years of trial and error to know what to conclude from the gauge readings), that one never knew if the gauges were being read accurately day-to-day or if the gauges were in good working order, and of course it all depended on the weather on the days I’d be there anyway. High melt rates at altitude won’t hit the lower river for…let’s see…guessing at that time lag is a shot in the dark, again unless one has gone through a few years of trial and error (and careful note-taking), watching gauges while looking at or standing in actual water.

    If I ever get up there I’d sure like to fish the Firehole. When it’s not tea-colored.

    Looking forward to Part II.

    – Mike

  3. Mike,
    The Firehole is at its best when high and tea-colored–no crowds and hungry fish. USGS gauges are but one data point in accessing the state of your favorite fishing spot. Indeed it takes some experience to understand what any given reading means. Actually it is somewhat irrelevant (within reason) how far away the gauge is from the spot you want to fish. For example, the closest upstream gauge to my favorite spot on the Big Hole is some 15 miles ++ upstream; yet I know if it is reading between 500-1000 CFS, my spot is in an ideal state for my style of fishing.

    There’s no evidence that I can find that USGS gauges are not accurate or not reliable (consistent readings). The only thing that messes with them is ice and severe flooding. At least here in Montana, most die hard anglers look at the gauge readings everyday, almost like reading the news. We depend on them. We take that data point, our knowledge of how any given watershed behaves on a seasonal and weather induced basis and make destination decisions. Maybe I should write more about it.

    I am sending you a link to a short video you might enjoy.


    1. I enjoyed that link very much Mike; thanks.

      Did not mean to disparage the USGS gauge system; we used to rely heavily on “windtalkers” (anemometers with synthesized voice outputs that are connected to a phone line) for wind strength and gust differential data prior to driving somewhere for soaring flight. Same principle, and such systems are quite handy. I have known some flow rate gauges in my own region that were broken for months and could name some that even to this day come up “no data posted” now and then, so that’s all I meant. I agree it doesn’t matter the distance…as long as you’ve calibrated the relationship between that gauge and your intended spot in your mind in advance.

      I have a psychological aversion to big brown water ever since my whitewater kayaking days, but I think I could get past it if the trout were hungry. 🙂 Also I suspect you don’t really mean opaque water up out of its banks and boiling everywhere you look.

      Tnx again for the link. Excellent.

      – Mike

Leave a Reply

Your email address will not be published. Required fields are marked *