The name “Trout Lake” is a bit of a misnomer. At barely 12 acres, “pond” would be a more apt description. Fortunately, the “trout” piece of the moniker is not exaggerated at all. In fact, Trout Lake contains some of the largest fish in all of Yellowstone Park. Located on a tiny tributary of Soda Butte Creek in the far northeastern corner of the park, Trout Lake sits in a small bowl adjacent to a beautiful alpine meadow. In the early 1900’s, the National Park Service ran a fish hatchery in Trout Lake, a testament to the lakes’ fertility. This led to the introduction of Rainbow Trout in the lake, though Cutthroat predominate. The tiny inlet stream, which is closed to fishing, is quite a sight during June and early July when it is packed with large spawning Cutthroats. It can be quite the spectacle, and I have witnessed otters and coyotes taking advantage of an easy meal. The fish in Trout Lake are impressive, with Cutthroats ranging from 14-22” and the Rainbows, while scarce, can run 20-30”. The downside to this is that the abundance of food that allows fish to attain these sizes also allows them to be picky in their feeding habits.
Special Note: Both the inlet stream and the small cove at the inlet are closed to fishing. Signs on the shore clearly mark this closure. Please respect this closure and do not harrass spawning fish.
Fishing Trout Lake
Trout Lake will fish best early in the summer. The lake gets very weedy later in the summer, making fishing extremely difficult. Since many of the fish are still spawning during June, sight fishing is the preferred method on Trout Lake. Fish that have completed their spawning run will move back into the lake and feeding will now be their priority. Subsurface fishing is the most effective method here. While you will see the occasional rise on the surface, there is so much aquatic life down below that the fish rarely have the need. Floating lines with bead head flies or a bit of split shot work fine, as do specialty sinking lake lines.
Your fly selection needs to a bit more precise here than your average mountain lake. Damselfly nymphs and scuds are both excellent choices. If choosing more generic nymphs like Pheasant Tails or Hares Ears, fish them in smaller sizes (#18) than you would on lakes with less discerning trout. A small wooly bugger or leach pattern is always worth a try.
You can sight fish effectively by two methods. One is to remain stationary and wait for a fish to cruise by. The other is to move slowly and carefully around the lake looking for fish. Typically some combination of both works best. Knowing where to present the fly is a trial and error game. Land your fly too close to the fish and you will spook him. Land too far away and the fish may change directions or your fly may sink out of view before it is spotted. Hopefully you will have enough chances to get it right. Trout Lake is small with a muck bottom, so avoid wading here.