When does the Olive Upright hatch?

April–July, typically 11:00–15:00. It starts from about 8°C, peaks around 12°C and tails off by 17°C.

What flies imitate the Olive Upright?

Olive Upright, Waterhen Bloa, Olive Comparadun, CDC Olive Emerger, typically on a #16–14 hook.

How big is the Olive Upright?

Spinner stage: 7–10mm. That matches a #16–14 hook.

Mayfly · Aquatic insect

Olive Upright

Rhithrogena semicolorata

Size

7–10mm

Hook size

#16–14

Hatch window

Season April–JulyPeak time 11:00–15:00

Water temperature

12° peak

8°17°

How fish feed on it

The yellow-bodied spinner returns to the rough water it came from. Broken surface makes it hard to see either the fly or the rise, so fish the seams where the current smooths off.

Flies that imitate this

Olive Upright

Waterhen Bloa

Olive Comparadun

CDC Olive Emerger

Ecology

Rivers & stillwaterAlpine riversSpate rivers

Where you'll find this

British IslesPresent
IberiaPresent
The AlpsPresent
ScandinaviaPresent
Continental EuropePresent
Atlantic fringePresent

Present throughout

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