Belly River Drainage in Glacier National Park Professional Review and Guide
"This eTrail includes these fishing destinations in the Belly River Drainage: Belly River, North Fork of the Belly River, Whitecrow Creek, Mokowanis River, Mokowanis Lake, Glenns Lake, Cosley Lake, and Elizabeth Lake. Species include: bull trout, rainbow trout, arctic grayling, mountain whitefish, brook trout, mountain whitefish, lake trout, and bull trout.
The fish are finicky and often hard to catch during the day, but in the evening you can usually get an 8-inch brookie or two without much effort. From fertile Elizabeth Lake, the grayling and rainbow populations sometimes drift downstream, making it possible to catch bigger fish in the river. Also,
because there are lake trout in Glenn and Cosley Lakes, it is possible to catch large predatory fish in the river."