Autumn in Yellowstone: Fewer People, Bigger Trout

Autumn, when the grizzly bears are adding fat for the winter and the weather is especially unpredictable, is not generally thought of as the best season for exploring Yellowstone National Park. But fall offers some of the year’s best fishing, with relatively few anglers.

Gone are the “bison jams,” half-mile-long lines at Park entrances, and also most of the tourists. But hatches, native cutthroat and other trout, scenic vistas, and spacious public lands remain. Fall in Yellowstone begins in earnest after Labor Day, when, by some fly shop estimates, about 80 percent of Yellowstone’s tourists are there to fish. Some of the Park’s most exciting fishing happens in September and October, like when the Drake Mackerels (Timpanoga hecuba) hatch on Slough Creek, Soda Butte Creek, and the Lamar River. Or when Shoshone Lake’s big brown and lake trout migrate into the Lewis Channel. And, of course, the famous run of Hebgen Lake browns and rainbows that gather in the Madison, Firehole, and Gibbon rivers also generates a fair amount of excitement among diehard fall fly fishers.

Hecubas

Timpanoga hecuba is a rare mayfly that occurs sporadically in the West. According to Ernest Schwiebert, this fall mayfly occurs from New Mexico to Colorado, Utah, Wyoming, Idaho, Montana and into Canada. It has many colloquial names, but in Yellowstone it’s often called the Drake Mackerel.

This anticipated hatch occurs mostly in the Park’s northeast quadrant: the Lamar River, Slough Creek, and Soda Butte Creek. These insects are the same size (#12) and shape as Western Green Drakes, and as a result, many people mistakenly identify them as Green Drakes. They have dark gray wings, and bodies varying from shades of tan and reddish brown to strawberry cream color. They emerge mostly on blustery overcast days, similar to Baetis weather.

Effective dry flies include the Adams, Purple Haze, or Brindle Chute. The Brindle Chute is a pattern developed on the Bitterroot for March Browns, but it is also a deadly hecuba imitation.

When nymphing, a bulky Hare’s Ear works well. Because hecubas emerge on streamside rocks, like stoneflies, rather than in water like most mayflies, emergers are not generally required or even effective.

I sometimes hear that the northeast corner of Yellowstone gets too cold to fish and “shuts down” by mid-October, but last October 15, a buddy and I found excellent fishing on both the Lamar and Slough Creek, and we didn’t see another angler all day.

Lewis River

The Lewis Channel, which connects Shoshone Lake to Lewis Lake in the Park’s southwest corner, receives large migrating brown trout and even larger lake trout from both lakes, starting in early September. Anglers can access this 3.5-mile section via a 3-mile hike on the Lewis Lake/Dogshead Trail (which follows the river and is an 11-mile loop trail), or you can canoe down to the channel from Shoshone Lake.

When the fish are in the channel and the weather is cooperative, this reach can feel a bit congested with people, though it’s rarely so busy that you can’t find yourself a great stretch to fish.

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Another more accessible option is to fish the Lewis River below Lewis Lake for the run-down browns and lake trout. These sizable trout fill the mile between the lake and Lewis Falls, which is accessed via a half-mile hike from Lewis Lake Campground.

A third, even more accessible option is to fish the Lewis River below Lewis Falls for lake-run browns from Jackson Lake in Grand Teton National Park. The falls act as a fish barrier for these buttery brutes, and fishing action can be fast.

The Lewis River drainage runs at an average of about 8,000 feet in elevation. Late September and early October are usually the best times to visit. By the last week of October 2019, the landscape was bright white under a foot of snow.

Lewis Lake Campground is one of only two that remain open until closing day for fishing in the Park, which occurs on the first Sunday in November. The other open campground is Mammoth Campground, which is open all year. But if winter comes early, it’s not very appealing camping.

Spawning Lake Trout

Fly fishers can sometimes feel a little helpless in the fight against Yellowstone Lake’s invasive lake trout, which have ravaged the native cutthroat trout population. But there are a couple of times each year when these deep-water predators become accessible to fly fishers: shortly after ice-out, and in the fall when the lake trout spawn along the lake’s shallow edges.

Candid fly fishers and Park biologists will tell you a number of places on Yellowstone Lake where you can target lakers at these times, most of which are in or near the lake’s West Thumb. The list includes the Carrington Island area, the West Thumb Geyser Basin shoreline (which is off limits to shore fishing, but boat fishing is possible), the mouth of Solution Creek, Rock Point, Pumice Point, and the spit at Arnica Creek. These latter four options can be fished from shore and, according to Todd Koel, the leader of Yellowstone’s Native Fish Conservation Program, they are best in the early morning and late evening. Boats are allowed on Yellowstone Lake with a permit, but unless you’re familiar with this intimidating lake’s geography and moods, it can be a little dangerous.

Carrington Island, located less than a quarter mile from the shore in the West Thumb’s northwest corner, is one of the most accessible and prolific spots for fall lakers. The greater area can be fished from shore, and it holds about half of the lake’s total spawning mackinaws. The island itself is very small—really just a rock outcropping with a lone pine tree—but the fish can be found in a wide radius around it. Streamers like white Clouser Minnows, Double Bunnies, and leech patterns are good flies.

According to recent news stories and Park reports, lake trout eradication efforts such as netting are making a dent in this nonnative population, so this might not be as viable an option in the future.

There are a lot of fickle timing elements to this endeavor, like when exactly the fish will be in the shallows to spawn, where exactly the fish will be in this vast sea, and dealing with the often cantankerous weather.

Icy roads (which regularly get closed entirely) can extend your travel time, modest winds can cause substantial whitecaps, and the shoreline can become shelf ice after a cold snap. Being that Yellowstone Lake is a long way to drive from almost anywhere, it can be difficult to justify the effort. Plus, sometimes it just feels a little silly casting a 9-foot rod from the shore of this huge lake.

Keep in mind that anglers are required to kill all lake trout they catch—they can be tossed back dead or kept to eat, and must be reported. Targeting spawning lakers is generally only ethically acceptable at places like Yellowstone Lake, due to the negative impacts the invasive species has had. Yellowstone National Park has other lake trout populations that should be allowed to spawn unencumbered by anglers.

The Madison’s Fall Run

Yellowstone’s main autumn event remains the Madison River’s Hebgen Lake spawning brown trout run. The Madison flows for about 18 miles within the Park from its headwaters to the boundary near Baker’s Hole Campground north of West Yellowstone. This is where the majority of Yellowstone’s fall anglers focus, pursuing the chunky lake fish that run out of Montana’s Hebgen Lake to spawn in the Park.

Named pools like Baker’s Hole, Beaver Meadows, the Barnes Pools, and the Cable Car Hole are ground zero for fishing buddy reunions, both planned and unplanned. This is what Chester Allen called “the social center of runner fishing” in his book Yellowstone Runners (CreateSpace Independent Publishing Platform, 2017).

Steelhead tactics are en vogue here—anglers can nymph, swing flies with two-handed rods, or simply pull streamers. Many of these lake fish run beyond the Madison into its headwater tributaries, the Gibbon and Firehole rivers. There aren’t many river miles in either before the fish hit their namesake falls, so the fish can be stacked in these short stretches. 

Another reason the Madison drainage is so popular is because of its access. Baker’s Hole Campground (which closes on October 1) is on U.S. Highway 191 outside of the west entrance. The Barnes Pools and Cable Car Hole are accessible via a gravel road less than a half a mile inside the Park gates. In contrast, Yellowstone Lake is about an hour and a half from the west or north entrances, and the Lewis Channel is about an hour and a half from either West Yellowstone or Jackson, Wyoming—the nearest hubs.

Streamside scuttlebutt in 2019 hinted that overall, fly fishers felt the runs have been a bit weak over the past couple of years. A prevailing theory is that this is due to Montana Fish, Wildlife & Parks’ cessation of stocking rainbow trout in Hebgen Lake four years ago. Studies then showed that the bulk of the rainbows reported caught in Hebgen Lake—87 percent according to a Bozeman Daily Chronicle article—were wild. No one was sure what became of the stocked rainbows in Hebgen Lake, so they stopped stocking them. Many fly fishers theorize that those stocked rainbows ended up as about 100,000 brown trout meals. Without this abundant forage over the past four years, Hebgen’s population of big brown trout suffered.

Angler satisfaction surveys released by Yellowstone National Park Fish Biologist Philip Doepke indicated that 2018 saw the fewest fish per Madison River angler in the past decade. Only 1.7 rainbow trout per angler per day and an average of only 1.5 browns per angler-day were landed in 2018, and 2.1 rainbows and 2.0 browns were averaged in 2019. In 2015, the numbers were 3.8 rainbows and 2.7 browns per day.

Miles Marquez, manager of Big Sky Anglers in West Yellowstone, does not believe this is because there are fewer fish.

“A good gauge was how well the lake fished this summer,” Marquez said. “And it fished fantastic.” He said that by mid-October of 2019, guides from Big Sky Anglers had caught a couple 2-foot browns, one 27-incher, and several other noteworthy fish. And later in 2019, an outfitter from nearby Big Sky shared photos on social media of a monumental 30-inch brown taken from the Madison in the Park.

Montana Fish, Wildlife & Parks Fisheries Biologist Dave Moser said he didn’t believe the lack of stocked rainbow trout in Hebgen plays any role in the fall run.

“A hundred thousand stocked rainbows as a percentage of total prey biomass in Hebgen is negligible,” Moser said. “Fall runs for both rainbows and browns can be quite variable. The run may be starting much later because of summer and fall temperature regimes of late.”

Marquez agreed that tough fishing was more likely due to odd weather than fewer fish or any other factor.

“Last year [2018] was sunny and warm. This year [2019], crazy cold. There have been more fluctuations in water color and temperature. We used to always have 45 degrees and rain for a week.”

Longtime Hebgen run fly fisher and Bozeman resident Larry Day observed that the fish didn’t seem to arrive until very late in the 2019 season. On the penultimate day of Yellowstone’s fishing season, Day said he encountered a group of five anglers at the Junction Pool—the exact headwaters of the Madison River—and they were catching one solid fish after another.

Closing Day

The closing day for fishing in Yellowstone (the first Sunday in November) is often a time for reflection. On the Firehole River, happy brown and rainbow trout continue to rise to mayflies and midges amid the ethereal geyser steam and the nearby heavy-footed bison.

“The geothermal activity keeps the water warm and keeps bug activity going into the cooler months,” said Josh Duchateau, outfitter at the Firehole Ranch on Hebgen Lake.

On the way to its mouth at the Madison River, the Firehole flows through three of the Park’s major geyser basins—the Upper, Midway, and Lower basins. Geyser water spews into the river, accounting for almost one quarter of the river’s flow by the time it meets the Gibbon and becomes the Madison. Thus, the Firehole’s water temperatures are significantly higher than normal river temperatures for this time of year. For example, the Firehole was 43 degrees prior to flowing through the basins and 53 degrees after on a recent November day. In comparison, the Madison River was 38 degrees.

Some friends and I had a tradition of fishing the Firehole on closing day as a way to, as Nate Schweber put it in his book, Fly Fishing in Yellowstone National Park (Stackpole, 2012), “be with friends and fish.”

A paper-flat hairpin curve near Grand Prismatic Spring known as Muleshoe Bend is a favorite hole to find these eager trout. Brown and rainbow trout from 12 to 16 inches explode onto your dry flies amid the sulfur smell and steam of nearby geysers. It’s a magical way to bid adieu to another wondrous year of fishing in the nation’s first national park.

   

*Joshua Bergan is a fly-fishing writer, photographer, and publisher based in Belgrade, Montana.