Edible dormouse nights and the 'polharjenje' season

Edible dormouse (Glis glis). Notranjska, Kočevsko, Loška dolina, beech forests country-wide, Slovenia.

Best time: 20 Aug – 5 Oct (August to October). Where: Snežnik castle forests, Kozarišče (Loška dolina), Kočevski Rog beech forests, Cerknica – Slivnica slopes (Slovenia). Time of day: Canopy activity starts at dusk, peaks between about 22:00 and 02:00 in mast years, and fades before dawn.

• You can go on your own
• Free
• No binoculars needed
• Sound 4/5

Open it in the interactive calendarSunrise and sunset listening times for the day you pick, and the map.

When is the best time?

Peak: 20 Aug – 5 Oct. Late August to early October in beech-mast years; traditional trapping opens 1 October

Active from 15 Jul to 20 Oct (July to October) in a typical year.

Time of day

Canopy activity starts at dusk, peaks between about 22:00 and 02:00 in mast years, and fades before dawn.

• Night canopy: last light → 02:00

What will you hear?

Squeals, churring and 'kissing' contact calls from the canopy, loud scrabbling on bark, beechnut shells raining down; in mast years the forest sounds like it is full of monkeys.

Binoculars?

No binoculars needed. Canopy sound 10–20 m up in the dark; a red torch or thermal imager for a glimpse, binoculars are useless.

Where to go

• Snežnik castle forests, Kozarišče (Loška dolina) — Heart of the dormouse-hunting tradition; the castle holds a dormouse collection. Beech forests all around. Map
• Kočevski Rog beech forests — Dormice are extremely abundant in mast years and are a main bear food in autumn. Map
• Cerknica – Slivnica slopes — Beech slopes above the lake; combine with the reedbed at dusk. Map

How to go on your own, and what it costs

Any beech forest track in a mast year: the Snežnik castle park and forest roads from Kozarišče, the Rog road, the Slivnica trail above Cerknica. Free, open at night; go in September before the trapping season starts on 1 October.

Cost: Free; Snežnik castle museum entry €8 adult (2026).

Field-recording notes

Dormouse vocalisation is a mast-year phenomenon — in a poor beechnut year the forest is nearly silent. The trapping season (1 Oct–30 Nov, permit-based, culturally important) brings people and lamps to the same forests from the first night of October, so record in September. Canopy sound is 10–20 m up: a vertical stereo pair or a boundary mic strapped to a trunk works better than ground-level rigs. Owls (tawny, Ural) hunt dormice and call over them. Dormice are legally huntable in Slovenia but the species is protected in most neighbouring countries.

Sources

• Total Slovenia News – dormouse hunting
• Dormouse hunting as part of Slovene culture (paper)

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More: all spectacles in Slovenia · wildlife at night · Slovenia in August · Slovenia in September · Slovenia in October