Boulder River 
The Boulder River originates in the rugged, high elevations of the Beartooth Mountains in the Gallatin National Forest. It tumbles down 7,300 feet and 60 miles through mixed conifers, deciduous trees, shrubs, grassland, and agricultural land, to join the Yellowstone River. Most of its drainage lies within the Absaroka-Beartooth Wilderness. The upper main Boulder cuts through a glacial valley from the headwaters to Two-Mile Bridge, flowing clear, cold and fast. This 22.5-mile segment combines rapids, riffles, plunges, long, wide pools, and short stretches of spawning and rearing habitat in a spectacular sub-alpine setting. As the river runs north 6.5 miles to Natural Bridge and Falls, its gradient lessens, resulting in clean gravels, riffles, runs, and deep pools. Below the Falls, for 4 to 5 miles, the Boulder meanders through agricultural land to its confluence with the East Boulder. Its final 28 miles from this point to the mouth are somewhat steeper and strewn with boulders and cobbles. The main Boulder, East and West Boulder rivers and their many tributaries provide a wide diversity of fisheries habitats and recreation opportunities, and sustain an agricultural economy. The system is part of the habitat required by fish from the Yellowstone River. It is subject to extreme runoffs, droughts, wildfire, mass wasting of soils and rock, and the impacts of agriculture, land development, and channelization. Upper portions of the main Boulder River are designated “Scenic” and have been considered for “Wild and Scenic” Classification.
Total Length: 65 miles
FWP Region: Region 5
Fishing District: Central Fishing District
Species Present
- Game Fish Opportunities:
-
Brook Trout, Brown Trout, Mountain Whitefish, Rainbow Trout
- All Species Present:
-
Brook Trout, Brown Trout, Longnose Dace, Longnose Sucker, Mottled Sculpin, Mountain Sucker, Mountain Whitefish, Rainbow Trout, Yellowstone Cutthroat Trout
NOTE: There may be game fish present (including
Species of Concern) that are not listed in the game fish category due
to low numbers for that fish. Until you identify your catch, please handle all fish carefully. Thank you.
Fishing Regulations
View the latest Montana Fishing Regulations.
Boating Regulations
Standard Boating Regulations for the State of Montana
Exceptions to Standard Boating Regulations by County
*Applies to all rivers & streams
| County |
Regulation |
Description & Exceptions |
| Park |
Closed to motorboats over 10 HP
|
Exception: Yellowstone River down river from Hwy 89 Bridge, near mouth of Shields River |
Fishing Pressure
Mouth to Boulder Falls (Nat Brdg) (River Mile: 0 to 37)
| Year |
Days Fished¹ |
Trips² |
State Rank³ |
Regional Rank³ |
| 2007 |
17,423 |
271 |
33 |
4 |
| 2005 |
14,536 |
252 |
49 |
9 |
| 2003 |
9,694 |
212 |
64 |
10 |
| 2001 |
12,616 |
231 |
50 |
10 |
| 1999 |
17,184 |
388 |
44 |
7 |
Boulder Falls (Nat Brdg) to Headwaters (River Mile: 37 to 65)
| Year |
Days Fished¹ |
Trips² |
State Rank³ |
Regional Rank³ |
| 2007 |
645 |
11 |
310 |
41 |
| 2005 |
1,517 |
26 |
215 |
28 |
| 2003 |
1,869 |
39 |
193 |
28 |
| 2001 |
924 |
18 |
265 |
40 |
| 1999 |
1,265 |
31 |
263 |
40 |
| ¹ Estimated yearly fishing use in angler days (one angler fishing one body of water in one day for any amount of time). |
| ² The number of times that a section of water was reported as having been fished (used to estimate the number of "Days Fished"). |
| ³ How this section of water ranked among all surveyed sections in the state or region, based on "Days Fished" in a survey year. |
| |
Gauging Stations
- Boulder River at Big Timber MT
- View Data
| River Mile: 2
