This may seem like a daft question, but if the hatch takes place over a couple of weeks, are there duns and spinners present on the water at the same time? If so, how do you work out which the trout are taking to inform fly choice
Thanks,
Simon

Not a stupid question at all.

The duns and spinners tend to be on the water at different times of day. For the most famous English "mayfly" (i.e. Ephemera danica or "The Mayfly"), hatches of duns tend to finish by late afternoon, whilst the spinners fall on the water around dusk (ish).

You can also look for clues in the way that the fish rise (see for example "The complete mayfly" DVD from FishOn productions). Rises to duns tend to be aggressive and splashy (or even aerial!). Spent spinners are usually sipped much more delicately.

If your taking one for the pot, spoon it........

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