The Boulder River in Montana is a picturesque tributary of the Yellowstone River, originating in the Absaroka-Beartooth Wilderness and flowing northward to its confluence near Big Timber. Spanning approximately 60 miles, the river offers diverse fly fishing opportunities amidst stunning landscapes. Its clear, fast-moving waters are home to healthy populations of rainbow and brown trout, making it a favored destination for anglers seeking both adventure and tranquility.
The Boulder River is typically divided into two main sections: the Upper Boulder and the Lower Boulder. The Upper Boulder, above Natural Bridge Falls, features fast pocket water and is accessible via the Main Boulder Road, offering opportunities for wade fishing amidst forested surroundings. The Lower Boulder, below the falls, flows through private lands and is characterized by swift currents and boulder-strewn waters, making it more suitable for float fishing with experienced guides.
Anglers can expect to encounter a variety of trout species in the Boulder River. The Upper Boulder is predominantly inhabited by rainbow and cutthroat trout, typically ranging from 10 to 14 inches. In the Lower Boulder, both rainbow and brown trout are prevalent, with some browns reaching up to 20 inches. The river's diverse habitats support a healthy and thriving trout population.
Trout in the Boulder River exhibit opportunistic feeding behaviors, adapting to the river's diverse insect hatches. Seasonal hatches include blue-winged olives, caddisflies, stoneflies, and terrestrials. During spring and early summer, trout are particularly active, feeding aggressively on emerging insects. Understanding these patterns can significantly enhance angling success.
Effective fishing methods on the Boulder River vary by section and season. In the Upper Boulder, wade fishing with dry flies and nymphs is productive, especially during hatch periods. The Lower Boulder, with its swift currents and limited access, is best approached via float fishing using rafts. Here, anglers often employ attractor dry flies, nymphs, and streamers to entice trout from their holding spots behind boulders and in deep pools.
Notable fishing spots along the Boulder River include the area downstream of Natural Bridge Falls, where the river widens and offers deeper pools ideal for trout. The confluence of the East and West Boulder Rivers also provides productive waters. Access points like Boulder Forks and Big Rock Fishing Access Site are popular among anglers seeking quality fishing experiences.
Access to the Boulder River varies along its course. The Upper Boulder is more accessible, with the Main Boulder Road paralleling the river and providing multiple entry points. In contrast, the Lower Boulder flows through predominantly private lands, limiting access. Public access sites such as Boulder Forks and Big Rock Fishing Access Site offer entry to this section, but anglers should be mindful of private property boundaries and obtain necessary permissions when required.
A versatile fly rod setup is essential for the Boulder River. A 9-foot, 5-weight rod is suitable for most conditions, paired with a floating line. For larger nymphs and streamers, a sink-tip line can be advantageous. Waders with sturdy boots are recommended due to the river's rocky and slippery terrain. Additionally, a wading staff can provide extra stability when navigating the swift currents and uneven riverbed.
Preserving the Boulder River's pristine environment is crucial for sustaining its trout populations. Anglers are encouraged to practice catch-and-release fishing, handle fish with care, and use barbless hooks to minimize harm. Being mindful of seasonal closures and adhering to local regulations helps protect spawning habitats and ensures the river remains a thriving fishery for future generations.
The Boulder River's swift currents and boulder-strewn waters require caution. Anglers should be aware of changing water levels, especially during spring runoff, which can create hazardous conditions. Wearing a personal flotation device (PFD) when floating, using a wading staff, and fishing with a partner are recommended safety practices. Always inform someone of your fishing plans and expected return time.
Local fly shops provide valuable resources for anglers, including current fishing reports, gear, and guided trips. In Big Timber, Sweetcast Angler offers a range of services tailored to the Boulder River. Additionally, Spring Creek Campground and Trout Farm provides information and amenities for visiting anglers.
Several organizations are dedicated to the conservation of Montana's fisheries. Trout Unlimited has a local chapter focused on preserving the Boulder River's ecosystem. The Montana Fish, Wildlife & Parks department also plays a vital role in managing and protecting the state's aquatic resources. Supporting these organizations through membership or volunteer work contributes to the ongoing health of the Boulder River.