When does the Small Dark Olive hatch?

June–October, typically 15:00–20:00. It starts from about 9°C, peaks around 14°C and tails off by 20°C.

What flies imitate the Small Dark Olive?

Greenwell's Glory, Tups Indispensable, CDC Olive Emerger, typically on a #18 hook.

How big is the Small Dark Olive?

Spinner stage: 4–6mm. That matches a #18 hook.

Mayfly · Aquatic insect

Small Dark Olive

Baetis scambus

Size

4–6mm

Hook size

#18

Hatch window

Season June–OctoberPeak time 15:00–20:00

Water temperature

14° peak

9°20°

How fish feed on it

A small dark fall in the evening, hard to see and easy to write off as nothing.

Flies that imitate this

Greenwell's Glory

Tups Indispensable

CDC Olive Emerger

Ecology

Rivers & stillwaterChalk streamsAlpine rivers

Where you'll find this

British IslesPresent
IberiaPresent
The AlpsPresent
ScandinaviaPresent
Continental EuropePresent
Atlantic fringePresent

Present throughout

About the genus Baetis

Baetis is a genus of mayflies of the family Baetidae, known as the blue-winged olive to anglers. There are at least 150 described species in Baetis . They are distributed worldwide, with the most variety in North America and northern Europe.

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