Big Lost River

Tributary of the Dry Channel Big Lost River

  • Recommended Fishing Water

Big Lost River in Butte and Custer Counties is 134.9 miles in length.

Interactive Map
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The Big Lost River drainage provides a high quality stream fishery for anglers. Species present include brook trout, rainbow trout, cutthroat trout and mountain whitefish. The scenery is outstanding, particularly in the upper reaches of the river. The river is intermittently dewatered downstream of the Blaine Diversion near the Rothwell Access site.

Facilities

Motor Restriction
No
Boat Ramp
No
Dock
No
Toilet
Yes
Campground
Yes
ADA Access
Yes

Directions

The Big Lost River drainage is located on the western edge of the Upper Snake Region. The river runs through the town of Mackay, and extends upstream to the Copper Basin. Make sure you have all the supplies you need before venturing past Mackay, as there are no services past this point. See the Fishing Planner Interactive Mapper for detailed information on facilities and access sites.

Recommended Game Fish

Species Observed in Surveys

Fish Stocking Records

Date Species Quantity General Size
2024/10/18 Henrys Lake Cutthroat Trout 5,950 Fingerling (3-6 inches)
2024/08/08 Rainbow Trout - Triploid 290 Catchable (12-14 inches)
2024/03/25 Rainbow Trout 200 Adults
2023/11/03 Rainbow Trout - Triploid 3,017 Fry (0-3 inches)
2023/11/02 Rainbow Trout 102 Adults
2023/10/31 Rainbow Trout - Triploid 1,644 Catchable (6+ inches)
2023/10/26 Rainbow Trout 232 Adults
2023/10/18 Rainbow Trout - Triploid 373 Catchable (12-14 inches)
2023/10/02 Rainbow Trout - Triploid 1,788 Catchable (12-14 inches)
2023/08/24 Rainbow Trout - Triploid 430 Catchable (6+ inches)
2023/08/01 Rainbow Trout - Triploid 434 Catchable (6+ inches)
2023/06/29 Rainbow Trout - Triploid 2,078 Catchable (6+ inches)
2023/05/01 Rainbow Trout 435 Catchable (15-19 inches)
2021/07/12 Rainbow Trout - Triploid 948 Catchable (12-14 inches)
2021/06/21 Rainbow Trout - Triploid 1,498 Catchable (12-14 inches)
2019/06/28 Rainbow Trout - Triploid 3,000 Catchable (6+ inches)
2017/04/27 Rainbow Trout 252 Adults
2016/10/14 Henrys Lake Cutthroat Trout 19,910 Fingerling (3-6 inches)
2016/09/22 Rainbow Trout - Triploid 1,000 Catchable (6+ inches)
2016/04/13 Rainbow Trout - Triploid 4,512 Fingerling (3-6 inches)
2006/09/22 Rainbow Trout - Triploid 1,710 Catchable (6+ inches)
2006/09/20 Rainbow Trout - Triploid 1,020 Catchable (6+ inches)
2003/06/25 Rainbow Trout - Triploid 26,400 Fry (0-3 inches)
2002/07/22 Rainbow Trout 900 Catchable (6+ inches)
2002/07/08 Rainbow Trout 500 Catchable (6+ inches)
2002/06/26 Rainbow Trout 500 Catchable (6+ inches)
2002/06/10 Rainbow Trout 525 Catchable (6+ inches)
2001/08/24 Rainbow Trout 350 Catchable (6+ inches)
2001/07/24 Rainbow Trout 518 Catchable (6+ inches)
2001/07/10 Rainbow Trout 500 Catchable (6+ inches)
2001/06/19 Rainbow Trout 500 Catchable (6+ inches)
2001/06/05 Rainbow Trout 499 Catchable (6+ inches)
2001/06/01 Rainbow Trout 400 Catchable (6+ inches)
2000/07/24 Rainbow Trout 500 Catchable (6+ inches)
2000/07/10 Rainbow Trout 500 Catchable (6+ inches)
2000/06/26 Rainbow Trout 500 Catchable (6+ inches)
2000/06/13 Rainbow Trout 500 Catchable (6+ inches)
1999/07/20 Rainbow Trout 612 Catchable (6+ inches)
1999/07/13 Rainbow Trout 340 Catchable (6+ inches)
1998/07/21 Rainbow Trout 1,013 Catchable (6+ inches)
1998/07/07 Rainbow Trout 585 Catchable (6+ inches)
1998/06/22 Rainbow Trout 1,050 Catchable (6+ inches)
1998/06/09 Rainbow Trout 578 Catchable (6+ inches)
1997/08/08 Rainbow Trout 120 Catchable (6+ inches)
1997/07/22 Rainbow Trout 576 Catchable (6+ inches)
1997/07/09 Rainbow Trout 580 Catchable (6+ inches)
1996/08/20 Rainbow Trout 60 Adults
1996/07/22 Rainbow Trout 780 Catchable (6+ inches)
1996/07/08 Rainbow Trout 750 Catchable (6+ inches)
1996/06/27 Rainbow Trout 1,500 Catchable (6+ inches)
1995/07/25 Rainbow Trout 756 Catchable (6+ inches)
1995/07/19 Rainbow Trout 760 Catchable (6+ inches)
1995/07/10 Rainbow Trout 750 Catchable (6+ inches)
1995/06/29 Rainbow Trout 791 Catchable (6+ inches)
1994/07/15 Rainbow Trout 750 Catchable (6+ inches)
1994/07/01 Rainbow Trout 790 Catchable (6+ inches)
1994/06/17 Rainbow Trout 765 Catchable (6+ inches)
1994/06/03 Rainbow Trout 590 Catchable (6+ inches)
1994/05/27 Rainbow Trout 167 Catchable (6+ inches)
1993/07/29 Rainbow Trout 750 Catchable (6+ inches)
1993/07/15 Rainbow Trout 787 Catchable (6+ inches)
1993/06/29 Rainbow Trout 760 Catchable (6+ inches)
1993/06/10 Rainbow Trout 760 Catchable (6+ inches)
1992/07/17 Rainbow Trout 570 Catchable (6+ inches)
1992/07/06 Rainbow Trout 475 Catchable (6+ inches)
1992/06/26 Rainbow Trout 256 Catchable (6+ inches)
1992/06/19 Rainbow Trout 475 Catchable (6+ inches)
1992/06/10 Rainbow Trout 247 Catchable (6+ inches)
1992/06/04 Rainbow Trout 247 Catchable (6+ inches)
1992/05/22 Rainbow Trout 440 Catchable (6+ inches)
1991/07/16 Rainbow Trout 850 Catchable (6+ inches)
1991/07/03 Rainbow Trout 756 Catchable (6+ inches)
1991/06/14 Rainbow Trout 770 Catchable (6+ inches)
1991/05/30 Rainbow Trout 813 Catchable (6+ inches)
1990/07/25 Rainbow Trout 750 Catchable (6+ inches)
1990/07/18 Rainbow Trout 250 Catchable (6+ inches)
1990/07/11 Rainbow Trout 750 Catchable (6+ inches)
1990/06/13 Rainbow Trout 750 Catchable (6+ inches)
1990/06/01 Rainbow Trout 750 Catchable (6+ inches)
1989/07/20 Rainbow Trout 800 Catchable (6+ inches)
1989/06/08 Rainbow Trout 1,476 Catchable (6+ inches)
1988/07/21 Rainbow Trout 1,540 Catchable (6+ inches)
1988/07/07 Rainbow Trout 1,680 Catchable (6+ inches)
1988/06/28 Rainbow Trout 1,540 Catchable (6+ inches)
1988/06/07 Rainbow Trout 1,650 Catchable (6+ inches)
1987/07/27 Rainbow Trout 440 Catchable (6+ inches)
1987/07/21 Rainbow Trout 1,320 Catchable (6+ inches)
1987/07/15 Brown Trout 37,060 Fingerling (3-6 inches)
1987/07/14 Brown Trout 29,920 Fingerling (3-6 inches)
1987/06/30 Rainbow Trout 2,640 Catchable (6+ inches)
1987/06/10 Rainbow Trout 220 Catchable (6+ inches)
1987/06/08 Rainbow Trout 2,640 Catchable (6+ inches)
1987/05/21 Rainbow Trout 220 Catchable (6+ inches)
1987/05/20 Rainbow Trout 2,640 Catchable (6+ inches)
1986/08/05 Rainbow Trout 4,650 Catchable (6+ inches)
1986/08/04 Rainbow Trout 1,500 Catchable (6+ inches)
1986/07/14 Brown Trout 81,600 Fingerling (3-6 inches)
1986/07/14 Rainbow Trout 4,650 Catchable (6+ inches)
1986/07/11 Rainbow Trout 1,500 Catchable (6+ inches)
1985/07/18 Rainbow Trout 756 Catchable (6+ inches)
1985/07/02 Rainbow Trout 4,951 Catchable (6+ inches)
1985/06/12 Rainbow Trout 2,040 Catchable (6+ inches)
1985/05/22 Rainbow Trout 1,500 Catchable (6+ inches)
1985/05/16 Rainbow Trout 2,500 Catchable (6+ inches)
1984/08/03 Brown Trout 29,575 Fry (0-3 inches)
1984/07/25 Rainbow Trout 9,400 Catchable (6+ inches)
1984/07/24 Rainbow Trout 4,700 Catchable (6+ inches)
1983/08/29 Rainbow Trout 4,568 Fingerling (3-6 inches)
1983/08/25 Rainbow Trout 1,575 Fingerling (3-6 inches)
1983/07/25 Rainbow Trout 5,250 Catchable (6+ inches)
1983/07/01 Rainbow Trout 1,576 Catchable (6+ inches)
1982/08/24 Rainbow Trout 1,560 Catchable (6+ inches)
1982/08/13 Rainbow Trout 1,045 Catchable (6+ inches)
1982/07/21 Rainbow Trout 1,440 Catchable (6+ inches)
1982/07/15 Rainbow Trout 2,990 Catchable (6+ inches)
1982/05/26 Rainbow Trout 3,600 Catchable (6+ inches)
1981/08/20 Rainbow Trout 812 Catchable (6+ inches)
1981/07/31 Rainbow Trout 1,612 Catchable (6+ inches)
1981/07/02 Rainbow Trout 11,410 Catchable (6+ inches)
1981/05/22 Rainbow Trout 1,800 Catchable (6+ inches)
1981/05/13 Rainbow Trout 2,400 Catchable (6+ inches)
1980/10/17 Brook Trout 150 Adults
1980/08/29 Rainbow Trout 2,160 Catchable (6+ inches)
1980/08/15 Rainbow Trout 1,500 Catchable (6+ inches)
1980/08/08 Rainbow Trout 540 Catchable (6+ inches)
1980/08/07 Rainbow Trout 1,620 Catchable (6+ inches)
1980/07/25 Rainbow Trout 1,400 Catchable (6+ inches)
1980/07/02 Rainbow Trout 1,860 Catchable (6+ inches)
1980/05/19 Rainbow Trout 4,000 Catchable (6+ inches)
1979/07/13 Rainbow Trout 1,980 Catchable (6+ inches)
1979/06/13 Rainbow Trout 2,300 Catchable (6+ inches)
1979/05/23 Rainbow Trout 4,830 Catchable (6+ inches)
1978/08/25 Rainbow Trout 3,080 Catchable (6+ inches)
1978/08/23 Rainbow Trout 220 Catchable (6+ inches)
1978/08/15 Brook Trout 495 Fingerling (3-6 inches)
1978/08/10 Rainbow Trout 4,440 Catchable (6+ inches)
1978/07/27 Rainbow Trout 1,665 Catchable (6+ inches)
1978/07/11 Rainbow Trout 2,988 Catchable (6+ inches)
1978/06/27 Rainbow Trout 2,520 Catchable (6+ inches)
1978/05/24 Rainbow Trout 2,700 Catchable (6+ inches)
1977/09/12 Rainbow Trout 8,401 Fry (0-3 inches)
1977/08/02 Rainbow Trout 2,520 Catchable (6+ inches)
1977/06/21 Rainbow Trout 1,440 Catchable (6+ inches)
1977/05/24 Rainbow Trout 1,320 Catchable (6+ inches)
1976/08/03 Rainbow Trout 2,900 Catchable (6+ inches)
1976/07/13 Rainbow Trout 2,062 Catchable (6+ inches)
1976/07/02 Rainbow Trout 2,160 Catchable (6+ inches)
1976/05/26 Rainbow Trout 4,800 Catchable (6+ inches)
1975/09/29 Rainbow Trout 5,600 Catchable (6+ inches)
1975/09/04 Rainbow Trout 3,300 Catchable (6+ inches)
1975/09/03 Rainbow Trout 3,800 Catchable (6+ inches)
1975/08/13 Rainbow Trout 2,000 Catchable (6+ inches)
1975/08/06 Rainbow Trout 1,920 Catchable (6+ inches)
1975/07/22 Rainbow Trout 4,800 Catchable (6+ inches)
1975/06/13 Rainbow Trout 4,200 Catchable (6+ inches)
1975/05/21 Rainbow Trout 3,800 Catchable (6+ inches)
1974/09/06 Rainbow Trout 3,500 Catchable (6+ inches)
1974/09/03 Rainbow Trout 3,360 Catchable (6+ inches)
1974/08/26 Rainbow Trout 3,300 Catchable (6+ inches)
1974/08/16 Rainbow Trout 1,920 Catchable (6+ inches)
1974/08/06 Rainbow Trout 2,160 Catchable (6+ inches)
1974/07/16 Rainbow Trout 2,160 Catchable (6+ inches)
1974/07/15 Rainbow Trout 1,800 Catchable (6+ inches)
1974/07/02 Rainbow Trout 3,500 Catchable (6+ inches)
1974/05/16 Rainbow Trout 1,800 Catchable (6+ inches)
1973/08/20 Rainbow Trout 2,200 Catchable (6+ inches)
1973/08/13 Rainbow Trout 2,800 Catchable (6+ inches)
1973/08/02 Rainbow Trout 2,040 Catchable (6+ inches)
1973/08/01 Rainbow Trout 1,360 Catchable (6+ inches)
1973/07/26 Brook Trout 15 Catchable (6+ inches)
1973/07/26 Rainbow Trout 45 Catchable (6+ inches)
1973/07/19 Rainbow Trout 1,800 Catchable (6+ inches)
1973/07/12 Rainbow Trout 3,200 Catchable (6+ inches)
1973/07/02 Rainbow Trout 4,480 Catchable (6+ inches)
1973/06/13 Rainbow Trout 3,840 Catchable (6+ inches)
1973/06/12 Rainbow Trout 1,920 Catchable (6+ inches)
1973/05/29 Rainbow Trout 3,840 Catchable (6+ inches)
1973/05/25 Rainbow Trout 1,440 Catchable (6+ inches)
1973/05/16 Brook Trout 600 Fingerling (3-6 inches)
1973/05/16 Rainbow Trout 2,400 Fingerling (3-6 inches)
1973/05/03 Rainbow Trout 4,560 Catchable (6+ inches)
1973/04/11 Rainbow Trout 3,900 Catchable (6+ inches)
1972/08/23 Rainbow Trout 900 Catchable (6+ inches)
1972/08/22 Rainbow Trout 3,720 Catchable (6+ inches)
1972/08/17 Rainbow Trout 1,680 Catchable (6+ inches)
1972/08/10 Rainbow Trout 3,120 Catchable (6+ inches)
1972/07/26 Rainbow Trout 1,800 Catchable (6+ inches)
1972/07/19 Rainbow Trout 6,080 Catchable (6+ inches)
1972/07/13 Rainbow Trout 1,680 Catchable (6+ inches)
1972/07/06 Rainbow Trout 4,080 Catchable (6+ inches)
1972/06/27 Rainbow Trout 3,600 Catchable (6+ inches)
1972/06/26 Rainbow Trout 1,500 Catchable (6+ inches)
1972/05/30 Brook Trout 240 Fingerling (3-6 inches)
1972/05/30 Rainbow Trout 1,280 Catchable (6+ inches)
1972/05/30 Whitefish 320 Fingerling (3-6 inches)
1972/05/17 Rainbow Trout 4,080 Catchable (6+ inches)
1972/04/19 Rainbow Trout 4,030 Catchable (6+ inches)
1971/09/14 Rainbow Trout 5,020 Catchable (6+ inches)
1971/09/08 Rainbow Trout 3,125 Catchable (6+ inches)
1971/09/07 Rainbow Trout 3,500 Catchable (6+ inches)
1971/08/27 Rainbow Trout 1,550 Catchable (6+ inches)
1971/08/25 Rainbow Trout 2,160 Catchable (6+ inches)
1971/08/18 Rainbow Trout 2,280 Catchable (6+ inches)
1971/08/10 Rainbow Trout 2,280 Catchable (6+ inches)
1971/08/02 Rainbow Trout 2,100 Catchable (6+ inches)
1971/07/28 Rainbow Trout 1,920 Catchable (6+ inches)
1971/07/26 Rainbow Trout 1,740 Catchable (6+ inches)
1971/07/19 Rainbow Trout 2,100 Catchable (6+ inches)
1971/07/13 Rainbow Trout 1,500 Catchable (6+ inches)
1971/07/08 Rainbow Trout 2,080 Catchable (6+ inches)
1971/06/30 Rainbow Trout 3,600 Catchable (6+ inches)
1971/05/26 Rainbow Trout 6,480 Catchable (6+ inches)
1971/04/09 Rainbow Trout 4,900 Catchable (6+ inches)
1970/08/31 Rainbow Trout 1,500 Catchable (6+ inches)
1970/08/27 Rainbow Trout 1,920 Catchable (6+ inches)
1970/08/24 Rainbow Trout 3,840 Catchable (6+ inches)
1970/08/19 Rainbow Trout 3,120 Catchable (6+ inches)
1970/08/18 Rainbow Trout 1,920 Catchable (6+ inches)
1970/08/07 Rainbow Trout 2,400 Catchable (6+ inches)
1970/07/31 Rainbow Trout 3,400 Catchable (6+ inches)
1970/07/30 Rainbow Trout 2,220 Catchable (6+ inches)
1970/07/22 Rainbow Trout 2,560 Catchable (6+ inches)
1970/07/13 Rainbow Trout 1,920 Catchable (6+ inches)
1970/07/02 Rainbow Trout 2,320 Catchable (6+ inches)
1970/06/18 Rainbow Trout 1,860 Catchable (6+ inches)
1970/06/03 Rainbow Trout 4,200 Catchable (6+ inches)
1970/05/19 Rainbow Trout 2,280 Catchable (6+ inches)
1970/05/06 Brook Trout 1,200 Fingerling (3-6 inches)
1970/05/06 Rainbow Trout 480 Catchable (6+ inches)
1970/04/09 Rainbow Trout 1,500 Catchable (6+ inches)
1970/04/04 Brook Trout 600 Fingerling (3-6 inches)
1970/04/04 Rainbow Trout 200 Fingerling (3-6 inches)
1970/04/04 Whitefish 1,200 Fingerling (3-6 inches)
1969/09/10 Rainbow Trout 1,750 Fingerling (3-6 inches)
1969/08/28 Rainbow Trout 1,920 Fingerling (3-6 inches)
1969/08/27 Rainbow Trout 5,280 Catchable (6+ inches)
1969/08/25 Rainbow Trout 4,200 Catchable (6+ inches)
1969/08/19 Rainbow Trout 4,560 Catchable (6+ inches)
1969/08/05 Rainbow Trout 4,200 Catchable (6+ inches)
1969/07/31 Rainbow Trout 2,640 Catchable (6+ inches)
1969/07/30 Rainbow Trout 2,800 Catchable (6+ inches)
1969/07/15 Rainbow Trout 3,960 Catchable (6+ inches)
1969/07/01 Rainbow Trout 1,920 Catchable (6+ inches)
1968/09/16 Rainbow Trout 3,600 Catchable (6+ inches)
1968/09/06 Rainbow Trout 3,600 Catchable (6+ inches)
1968/08/29 Rainbow Trout 1,400 Catchable (6+ inches)
1968/08/23 Rainbow Trout 2,100 Catchable (6+ inches)
1968/08/07 Rainbow Trout 2,700 Catchable (6+ inches)
1968/07/23 Rainbow Trout 1,500 Catchable (6+ inches)
1968/07/22 Rainbow Trout 1,500 Catchable (6+ inches)
1968/07/16 Rainbow Trout 1,560 Catchable (6+ inches)
1968/07/10 Rainbow Trout 1,620 Catchable (6+ inches)
1968/06/18 Rainbow Trout 1,740 Catchable (6+ inches)
1968/05/28 Rainbow Trout 1,500 Catchable (6+ inches)
1968/05/08 Rainbow Trout 3,990 Catchable (6+ inches)
1968/04/24 Rainbow Trout 1,720 Catchable (6+ inches)
1968/04/02 Rainbow Trout 5,280 Catchable (6+ inches)
Source: IDFG Fish Stocking Database.

Licenses and Tags

Learn more about IDFG Licenses, Tags & Permits
 

The Big Lost River has a 6-trout limit from Memorial Day weekend to December 1, and is one of the few places where anglers can harvest Yellowstone Cutthroat Trout from a stream. However, please remember Mountain Whitefish are catch-and-release only year-round to protect this unique population. 

Fishing Rules, 2025 - 2027

All Waters Open All Year

Except as modified in Special Rules
Fishing is not allowed within the posted upstream and downstream boundary of any fish weir or trap.

Daily Bag Limits

The following daily bag limits apply to all waters within each region except as modified in the Special Rules. The possession limit is 3-times the daily bag limit.

Special Rules

Big Lost River and tributaries
  • December 1 through Friday before Memorial Day weekend – trout – catch-and-release; (except Brook Trout); whitefish – catch-and-release
  • Saturday of Memorial Day weekend through November 30 - trout limit is 6; whitefish – catch-and-release
Upper Snake Region Bag Limits
Bass (Largemouth and Smallmouth)

  • Bass - no bag, length, or possession limits

Brook Trout

  • Brook Trout limit is 25
  • Harvest allowed during any open season unless otherwise noted under Special Rules - if gear or bait restrictions are listed, they apply when fishing for Brook Trout

Bull Trout

  • Bull trout - catch-and-release

Kokanee

  • Kokanee limit is 15

Sturgeon

  • Sturgeon - catch-and-release
  • Sturgeon must not be removed from the water and must be released upon landing
  • Barbless hooks, sliding swivel device to secure a weight, and a lighter test line to secure weight to sliding swivel device are required. See fishing regulations for details

Tiger Muskie

  • Tiger Muskie limit is 2, none under 40 inches

Trout includes Brown Trout, Golden Trout, Lake Trout, Arctic Grayling, Cutthroat Trout, Rainbow Trout, and trout hybrids (e.g. Tiger Trout)

  • Trout limit is 6, all species combined
  • Bull Trout and Brook Trout are listed separately

Walleye (Have not been stocked intentionally in this Region. May be harmful to existing fisheries.)

  • No bag, length, or possession limits, harvest is encouraged

Whitefish

  • Whitefish limit is 25 - see Big Lost River exception
  • Harvest allowed during any open season unless otherwise noted under Special Rules - if gear or bait restrictions are listed, they apply when fishing for whitefish

Protected Nongame Fish including Bluehead Sucker (also known as Green Sucker)

  • May not be harvested or possessed

All Other Fish Species includes bullfrogs and crayfish

  • No bag, length or possession limit
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