Mayfly · Drunella grandis in the West, Ephemera guttulata in the East
Green Drake
Also called Drake, Western green drake, Eastern green drake.
Short answer
The green drake is a large mayfly, hook size 8 to 12, whose hatch lasts only a week or two but brings the biggest trout in a river to the surface. Western and eastern green drakes are different insects with the same nickname. Anglers plan holidays around it, and the timing is notoriously hard to catch.
What a green drake is
Two quite different insects share this name. In the West, Drunella grandis is a stout olive-green mayfly of fast freestone water, hatching in late June and July. In the East, Ephemera guttulata is a bigger, paler, cream-and-olive burrowing mayfly whose famous emergence on Penns Creek and the Delaware comes in late May and early June, followed by the ghostly white spinner fall anglers call the coffin fly. What they have in common is size and consequence: both are large enough that a trout which has spent the year eating size 20 insects will abandon caution for them, and both hatch for a short, unpredictable window.
- Hook size
- Hook sizes 8 to 12
- Colour
- West: dark olive-green body, slate wings. East: cream to pale olive body, heavily mottled wings
The stages trout eat
- Nymph
- Large and conspicuous. Eastern drakes burrow in silt; western drakes crawl in fast rocky water.
- Emerger
- A big insect takes a long time to get out of its shuck, and trout take full advantage.
- Dun
- Unmistakable — a mayfly the size of a small moth drifting down the current.
- Spinner
- The eastern coffin fly, white and spectral, falling at dusk. One of the great sights in fly fishing.
When does the green drake hatch?
| When | What is happening |
|---|---|
| Late May – early June | The eastern hatch. Penns Creek and the Upper Delaware, and crowds to match. |
| Mid-June | The eastern hatch moves upstream and north; the Catskills and northern Pennsylvania. |
| Late June – July | The western hatch on Colorado and Idaho freestone water, moving upriver as the season warms. |
| July | High-altitude western rivers — the Fryingpan and the Roaring Fork — at the tail of the season. |
Emergence dates move with latitude, altitude and the weather of a given year. Treat these windows as a shape, not a diary, and check a local report before you travel.
Where it matters
In the East, Penns Creek, the Upper Delaware and the Catskills. In the West, the Henry's Fork, the Fryingpan, the Roaring Fork and the McKenzie. The state pages for Pennsylvania, New York, Colorado, Idaho and Oregon all name it in their season calendars.
Fly fishing in Pennsylvania Fly fishing in New York Fly fishing in Colorado Fly fishing in Idaho Fly fishing in Oregon
How to fish it
Be there. That is most of it — the hatch lasts days, not weeks, and shops and forums track it hour by hour. When it is on, fish a larger tippet than you normally would, because the fly is heavy and the fish are big. Many anglers do better in the hour before the hatch on a drake nymph, and better again at dusk on the spinner, than in the chaos of the hatch itself.
- Western and eastern green drakes are different insects. Buy flies for the one you are fishing.
- The spinner fall often beats the hatch, and almost nobody stays for it.
- If you miss the drakes by a week, go upstream or uphill — the hatch climbs as the season warms.
Flies that imitate it
Each of these is a card in the deck, and each has a full page in Our Fly-brary.
Keep reading
- Dry fly vs nymph — which stage to fish, and when
- Why trout refuse your fly — usually the wrong stage, not the wrong pattern
- Best time of day to fly fish — the daily logic behind the table above
- Our Fly-brary — every fly in the deck, explained