What is happening here is a super cool phenomenon that happens at the beginning of the season at Grosvenor. The year's salmon smolt get funneled through the narrows where Grosvenor is located on their way towards the ocean. Because of this, tons of rainbow trout and lake trout corral these smolt in a feeding frenzy. Birds tend to flock to the area because fish are forcing the smolt to the surface, and as you can see hundreds of fish are typically boiling on the surface as they feed on the smolt. This is an angler's dream for dry fly fishing.
bristoladventures.com/lodges/...