Bighorn River
Hatch Guide: Bighorn River - Fort Smith, Montana
| Hatch Timing | Scientific Name | Common Name | Hook Size |
| Mar 1-May 31 | Family Chironomidae | Midge | 16-24 |
| Mar 1-Apl 30 | Skwala parallela | Skwala Stone | 8-12 |
| Apl 1-Jun 30 | Baetis species | Blue Winged Olive | 16-20 |
| Apl 1-May 31 | Siphlonurus alternatus | Gray Drake | 8-10 |
| Apl 1-May 31 | Stenonema vicarium | March Brown | 10-12 |
| May 1-Jul 31 | Ephemerella inermis | Pale Morning Dun (PMD) | 16-20 |
| May 15-Jul 31 | Claassenia sabylosa | Golden Stonefly | 2-4 |
| Jun 1-Aug 31 | Paraleptophlebia debilus | Mahogany Dun | 14-16 |
| Jun 1-Jun 30 | Pteronarlys calfornica | Salmonfly | 4-6 |
| Jun 1-Aug 15 | Genus Cheumatopsyche | Little Sister Sedge | 10-16 |
| Jun 1-Jul 31 | Ephemera simulans | Brown Drake | 10 |
| Jun 1-Jul 31 | Ephemerella doddsi | Green Drake | 10 |
| Jun 15-Jul 31 | Dicosomoecus jucundus | Giant Orange Sedge | 4-8 |
| Jun 24-Sept 21 | Isoperla patricia, I. marmona | Yellow Sally | 14-16 |
| Jul 1-Jul31 | Arctpsyche grandis | Great Grey Spotted Sedge | 6-10 |
| Aug 1-Sep 30 | Tricorythodes mintus,T.fallus | Trico | 18-22 |
| Aug 1-Nov 31 | Family Chironomidae | Midge | 16-24 |
| Sep 1-Nov 31 | Baetis species | Blue Winged Olive | 16-20 |
| Terrestrials | |||
| Apl 15-Sep 15 | Family Coleoptera | Beetles | 10-12 |
| Jun 1-Aug 30 | Family Formicidae | Ants | 14-16 |
| Jul 1-Sep 30 | Family Tettigoniidae | Grasshoppers | 8-12 |