Terrestrial · Order Coleoptera
Beetle
Also called Japanese beetle, Terrestrial beetle.
Short answer
Beetles fall into rivers all summer and sink immediately, which is why they catch fish that refuse everything else. They are the most under-used terrestrial in fly fishing, they need no hatch to work, and a size 14 black beetle drifted along a shaded bank is one of the most reliable summer flies there is.
What a beetle is
Beetles are the quiet workhorse of summer terrestrial fishing. They are abundant in streamside vegetation everywhere, they fall in constantly, and they are heavy enough that they sink or ride awash rather than perching on the surface. Trout eat them with no hesitation at all — a beetle is a solid mouthful with no legs thrashing and nothing to inspect. On small wooded streams in the Appalachians they are arguably the single most useful fly in the box from June to September, and on hard-fished eastern limestone water a sunk beetle takes fish that have refused mayfly imitations all morning.
- Hook size
- Hook sizes 12 to 18
- Colour
- Black above all, with peacock, green and iridescent versions that match Japanese beetles
The stages trout eat
- Adult
- The only stage anglers fish. Falls in from overhanging trees and banks.
- Drowned
- Beetles sink readily. Fished just subsurface they are more realistic than floating.
When does the beetle hatch?
| When | What is happening |
|---|---|
| June | Beetles become numerous as vegetation thickens. Fishing improves through the month. |
| July – August | Peak, especially on streams with heavy overhanging cover. |
| September | Still strong, and overlapping with ants and hoppers. |
| First frost | Finished for the year, like all terrestrials. |
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
Wooded streams above all: Shenandoah National Park, the Smokies, Pennsylvania limestone creeks, New England hill streams, the Driftless coulees. The Virginia, Pennsylvania and Maryland pages all name terrestrials in their summer calendars.
Fly fishing in Virginia Fly fishing in Pennsylvania Fly fishing in Maryland Fly fishing in North Carolina Fly fishing in Wisconsin
How to fish it
Drift it tight to the bank, under the branches, where the naturals actually fall. Add a tiny strike indicator or fish it behind a visible dry if you cannot track it, because a sunk beetle is invisible and you will miss takes. A deliberate plop on landing helps rather than hurts — a beetle hitting the water makes a noise, and trout have learned what that noise means.
- Cast under the branches, not into the middle of the river. That is where beetles fall.
- Let it sink. A beetle riding high is the wrong silhouette.
- If you cannot see it, fish it eighteen inches behind a visible dry.
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