Montana Missouri River Fish Survey

Just heard from FW&P over in Region 4, that’s the area along the Rocky Mountain Front with headquarters in Great Falls. With all the focus on hunting and colder weather no one is thinking much about fishing. Fly fishers are at their benches and vises creating the next great pattern. Judging by the latest fish survey numbers the Missouri may be the place to put those patterns to the test next season.

Fish surveys this year indicate rainbow and brown trout numbers remain above the long-term average in the Missouri River between Holter Dam and the town of Cascade. State fisheries crews this fall estimated 5,194 rainbow trout greater than 10 inches long per mile near the town of Craig on the Missouri. Not only is that above the long-term average of 3,174 rainbows per mile, but continues a trend of above average numbers over the past three years: 6,034 per mile in 2011 and 7,312 in 2012.

This year’s population was bigger in size and slightly lower in abundance than the past two years, says Fish, Wildlife and Parks fisheries biologist Grant Grisak, which is typical as the current population reaches its maximum size.

“This year,” Grisak says, “87 percent of the rainbow trout in the Craig section were 15 inches long or greater, and 35 percent of the population was 18 inches long or longer.”  Next year, the population should return to normal levels, unless an unusually high water event occurs in the spawning tributaries, Grisak says. High water in the Missouri River tributaries typically results in high rainbow trout production.