Fly Fishing Hatch Chart
A season by season look at the major mayfly, caddis, stonefly and terrestrial hatches.
Open tool : Fly Fishing Hatch ChartMadison River Hatch Chart
What comes off the Madison, roughly when, and what size to carry. Timing moves every season with snowpack, flow and water temperature.
Showing every hatch in the chart.
Madison River hatches
| Hatch | Usual months | Hook sizes | Notes |
|---|---|---|---|
| Midge | Year round, best December to March | 18 to 22 | Slow side channels and soft edges. Fish them before noon. |
| Blue winged olive, spring | Late March to May | 14 to 18 | Overcast days bring the strongest emergence, especially on the Lower Madison. |
| Skwala stonefly | Early April | 8 to 10 | Warm afternoons. A short early season window that is easy to miss. |
| March brown | Late April to mid May | 10 to 14 | Most are size 12. Both the Upper and Lower Madison can fish well. |
| Mother's Day caddis | Late April to May | 14 to 16 | The bulk of it is on the Lower Madison. Runoff shuts it down in some years. |
| Salmonfly | Mid June to mid July | 4 to 8 | The hatch that made this river. Starts low and crawls upstream over a few weeks. |
| Golden stonefly | Late June to July | 8 to 12 | Follows the salmonfly upstream by about a week. |
| Pale morning dun | Late June to August | 14 to 18 | Cloudy mornings. The fifty mile riffle above Ennis is prime water for it. |
| Spruce moth | Mid July to mid August | 14 to 16 | Reported above Ruby Creek, near pines and bankside brush. |
| Terrestrials | Mid July to September | 6 to 14 | Hoppers, ants and beetles along the banks. Best once the wind picks up. |
| Callibaetis | Late July to September | 14 to 16 | Slower water, side channels and flats rather than the fast riffles. |
| Trico | August to early September | 20 to 24 | Early morning spinner falls on slick water. Long leader, fine tippet. |
| Caddis | May to October | 14 to 18 | Evening activity right through the summer on the Upper Madison. |
| Blue winged olive, fall | September to October | 16 to 22 | Overcast afternoons, and reported strongest through the canyon. |
| Sculpin and streamers | Year round, best in autumn | 2 to 8 | Not a hatch. Pre spawn brown trout respond to big flies in October and November. |
Three rivers wearing one name
The Madison does not fish as a single river, and a chart that pretends otherwise will put you on the wrong water. Inside Yellowstone Park it is a slow meadow stream. Between Quake Lake and Ennis it becomes the fifty mile riffle, a long continuous run of pocket water that holds the salmonfly hatch this river is known for. Below Ennis Lake the Lower Madison is wider, slower and considerably warmer.
That last difference matters more than any fly selection. The Lower Madison warms fast in midsummer, which is why the Mother's Day caddis is a Lower Madison event in spring and why the same stretch can be a poor choice in late July. The upper river stays colder and fishes through the summer.
The salmonfly hatch is the clearest example of timing over geography. It does not happen everywhere at once. It starts on the lower water in mid June and works upstream over the following weeks, so the same calendar date puts you in the middle of it or a month early depending on where you park.
Check conditions before you drive
Montana Fish, Wildlife and Parks publishes drought and temperature related fishing restrictions each summer, and stretches of the Madison have been affected in past seasons. Those restrictions are the rules that actually apply. Check them before you go rather than after.
Carry a thermometer and use it. The Trout Water Temperature Guide in these tools covers the ranges commonly published for when trout feed and when they are better left alone, and the Lower Madison in August is exactly the situation those ranges exist for.