Soča River · hatch chart
Marble trout from 1 April; grayling from 16 May; the season closes at the end of September
By month
JanFebMarAprMayJunJulAugSepOctNovDec
| Month | Insect | Stage | Size | Time | Intensity |
|---|---|---|---|---|---|
| Apr | Large Dark Olive (Baetis rhodani) | Dun | #14 | 13:00-16:00 | |
| May | March Brown (Rhithrogena) | Dun | #12-14 | 11:00-16:00 | |
| Jun | Blue-Winged Olive (Serratella) | Dun at dusk | #16-18 | 19:30-22:00 | |
| Jun | Caddis (Rhyacophila) | Adult, evening | #12-14 | 20:00-23:00 | |
| Jul | Yellow mayfly (Potamanthus) | Dun | #12 | 20:00-22:30 | |
| Sep | Blue-Winged Olive (Serratella) | Spinner fall | #16-18 | 14:00-17:00 |
Flow and visibility
The Soča is a karst alpine river: after rain in the Julian Alps it can rise a metre in a few hours and turn from turquoise to milky grey-green, which is why locals fish the morning and watch the afternoon sky. Peak clarity is usually in the morning before the day's snowmelt arrives from the high tributaries. Water temperature in the upper valley rarely exceeds 14°C, even in August.
The insect plate
