Every fish, every river, every fly — illustrated with real photography, annotated by naturalists, and kept in your pocket. Begin your own collection today.
Enter the compendium →1,200+ species, sourced from iNaturalist and enriched with our own notes on habitat, season, and what they're biting.
Plate I
Plate II
Plate III
Plate IVThe West's native trout, named for the crimson slash beneath the jaw. A willing riser to a well-placed dry fly, it holds in cold, clean freestone rivers and alpine lakes — a barometer for the health of the water it lives in.