Hatch Chart
Hatch timing is highly dependent on weather, water conditions, and temperatures. The dates and information provided are intended as general guidelines, and may vary from year to year.
| Dates | Hatches | Size | Imitations (Patterns) |
|---|---|---|---|
| March 1 - May 15 | Midges | 18-20 | Griffiths Gnat, Emerging Midge, Parachute Adams |
| April 1 – May 15 | Blue winged Olive (BWO) | 18 | Blue Winged Olive, CDC Biot BWO, Adams, BWO Nymph |
| May 15 - June 15 | March Brown | 14-16 | March Brown, Adams |
| May 20 - August 30 | Caddis | 10-18 | Elk Hair Caddis, Parachute Caddis, Slow Water Caddis, Flashback Caddis Nymph |
| June 15 - August 15 | Golden Stonefly | 6-12 | Yellow and Orange Stimulators, Kauffman’s Stone Nymph, Brook’s Stonefly Nymph |
| July 15 - August 15 | Western Green Drake | 8-12 | Green Drake, Green Paradrake, Thorax |
| July 15 - September 15 | Grasshopper | 4-12 | Dave’s or Whitlock’s Hopper, Club Sandwich, Triple Decker |
| July 15 - October 1 | Ants (Black & Red) | 14-20 | Parachute Ant, Foam Ant, Fur Ant |
| August 1 - October 1 | Tricos | 18-22 | Trico Spinner, Adams, CDC Biot Trico |
| August 15 - October 1 | Fall Caddis | 6-8 | Mikaluck Sedge, Goddard Caddis, Stimulator (Orange, Brown & Green) Elk Hair Caddis |
| September 1 - August 15 | Blue Winged Olive | 18-20 | CDC Biot BWO, BWO, Adams |
| Year Round | Midges (when temperature permits) | 16-22 | Black Gnat, Griffith’s Gnat, Chironomid Nymphs |
Other Popular & Versatile Patterns
- San Juan Worm (Wire & Chenille versions): Size 2-14
- Chernobyl Ant: Size 6-12
- Gold Ribbed Hare’s Ear Nymphs (Bead Head): Size 12-16
- Pheasant Tail Nymphs (Bead Head): Size 14-18
- Mini Leeches, Balanced Leeches in the Fall & Winter: Size 10-14
- Back Swimmers (Prince Nymph, Foam Water Boatman) in the Fall & Winter: Size 10-14
- Foam Beetle, Deer Hair Beetle in the Fall: Size 12-16
- Prince Nymph (Bead Head): Size 12-18
- Clouser Minnow: Size 2-10
- Wooly Buggers & Bow River Buggers: Size 2-10
Includes the Crowsnest and Livingstone Rivers
| Dates | Hatches | Size | Imitations (Patterns) |
|---|---|---|---|
| March 15 - May 30 | Tiny Winter Black | 12-16 | Pheasant Tail Nymph |
| April 15 - June 15 | Blue Winged Olive (BWO) | 18-20 | CDC Biot BWO, Thorax BWO, BWO Dry and Nymph |
| May 15 - June 15 | March Brown | 12-14 | March Brown, Thorax MB |
| May 15 - June 25 | Salmon Fly | 4-8 | Orange Stimulator, Fluttering Stone, Bird’s Stone, Improved Sofa Pillow |
| May 20 - August 30 | Caddis | 12-18 | Elk Hair Caddis, Parachute Caddis, Latex Caddis Nymph, Flashback Caddis Nymph |
| June 1 - July 15 | Golden Stonefly | 6-10 | Yellow Stimulator, Improved Sofa Pillow |
| June 5 - August 20 | Little Yellow Sally | 10-14 | Elk Hair & Parachute Caddis (Yellow Body), Little Yellow Stone, Gold Ribbed Hare’s Ear Nymph |
| June 5 - July 30 | Quill Gordon | 14-16 | Quill Gordon, Light Cahill |
| June 15 - July 25 | Pale Morning Dun (PMD) | 16-18 | CDC PMD, PMD Dry, Light Cahill, Parachute PMD, PMD Spinner |
| June 15 - July 15 | Western Green Drake | 8-10 | Green Drake Dry, Olive Paradrake, Green Humpy |
| July 5 - August 5 | Small Western Green Drake | 12-16 | Green Drake Dry, Green Humpy |
| July 15 - September 15 | Grasshopper | 4-12 | Dave’s & Whitlock’s Hopper, Club Sandwich, Charlie Boy, Spent Hopper |
| July 15 - October 1 | Ants (Red or Black) | 14-20 | Parachute Ant, Foam Ant, Fur Ant, Transpar-ant |
| August 5 - October 5 | Fall Caddis (Sedges) | 6-10 | Goddard Caddis, Orange, Green & Brown Stimulator, Mikaluk Sedge, Elk Hair Caddis |
| September 1 - October 15 | Blue Winged Olive (BWO) | 18-20 | CDC Biot BWO, Thorax BWO, BWO Dry and Nymph |
Other Popular & Versatile Patterns
- San Juan Worm (Chenille & Wire): Size 2-14
- Prince Nymph: Size 12-18
- Pheasant Tail Nymph: Size 2-18
- Gold Ribbed Hare’s Ear: Size 12-16
- Kaufmann’s Stonefly Nymph: Size 4-10
- Montana Stonefly Nymph: Size 4-10
- Royal Wulff & Royal Trude: Siz e 12-16
- Griffith’s Gnat: Size 12-22
- Chernobyl Ant: Size 8-14
- Turk’s Tarantula: Size 8-12
- Wooly Bugger: Size 6-10
- Clouser Minnow: Size 4-10
Includes Rivers such as North and South Ram, Stouffer Creek, and Clearwater
*Applies more to Higher Elevation and mountain streams such as those indicated above, than lower elevation Foothills streams hatches.
| Dates | Hatches | Size | Imitations (Patterns) |
|---|---|---|---|
| June 1 - August 30 | Caddis | 12-18 | Elk Hair Caddis, Parachute Caddis, Slow Water Caddis, Latex Caddis Nymph, Flashback Caddis Nymph |
| July 1 - August 15 | Golden Stonefly | 6-12 | Orange and Yellow Stimulator, Yellow Montana Stone, Kauffman’s Golden Stone |
| July 15 - August 15 | Western Green Drake | 10-12 | Green Drake Dry, Thorax Green Drake, Parachute Green Drake, Olive Paradrake |
| August 1 - September 25 | Grasshopper | 6-12 | Dave’s & Whitlock’s Hopper, Club Sandwich, Charlie Boy |
| August 15-September 15 | Blue Winged Olive (BWO) | 18-20 | CDC Biot BWO, BWO Dry, Parachute BWO, BWO Spinner |
Other Popular & Versatile Patterns
- H&L Variant Size 12-16
- Griffith’s Gnat: Size 12-18
- Adams: Size 12-16
- Turk’s Tarantula: Size 8-12
- Chernobyl Ant: Size 8-14
- Royal Wulff & Trude: Size 12-16
- Wooly Bugger: Size 8-10