Owl Lake

Drainage: Stillwater
Approaches: Approximately 14 miles one way on the Upsidedown Trail, all on trail, with 3,700 feet up and 700 down. FWP also puts it at roughly 12 trail miles from the West Fork Stillwater trailhead.
Elevation: 9,594 feet
Fish: Yellowstone cutthroat and rainbow hybrids, common and self-sustaining. Montana FWP.
Coordinates: 45.27554, -110.09905
Bugs: Mosquitoes, just bad enough to be annoying.

Getting there

On trail from either the Upsidedown or the West Fork Stillwater side. No route-finding.

We came at it mid-traverse from a camp at Wounded Man, by way of Diaphanous. Owl is about eight tenths of a mile southwest of Diaphanous and 17 feet below it, and we were in its ground for a bit over half an hour.

The hike

Owl is 14.4 acres and 30 feet at the deepest, with a 13-foot average.

FWP classes the fish as cutthroat-rainbow hybrids but notes that what is actually swimming there looks like pure rainbow. They are big and they are hard to catch. The 2025 crew fished it with a rod, called the fishing slow, said they observed a few large rainbows, and landed exactly one — at 19.6 inches. In 2018 they got seven averaging 13.9 with one at 19.5.

Two surveys, seven years apart, both turning up fish in the nineteens.

FWP says there are some good places to camp with firewood nearby.

Tips & safety

• Navigation: On trail from either trailhead. Eight tenths of a mile southwest of Diaphanous if you are working across the plateau.

• Camping: Some good spots with firewood nearby.

• Fishing: Slow, and worth it. Fish to nearly 20 inches in both of FWP's last two surveys, and their 2025 crew landed one fish in a session.

• Bugs: Mosquitoes, annoying rather than bad.