Sort Sol in Tondermarsken

Sort Sol, the black sun, is the local name for the starling murmurations over the reed beds of the south Jutland marsh in spring and autumn, when birds gathering to roost mass in the air in numbers reaching several hundred thousand and move as a single body, darkening the sky at dusk, which is where the name comes from. The birds feed on the wet meadows through the day and come in as the light goes, and the display can last twenty minutes or an hour depending on weather and on whether a raptor is present, which tightens the flock dramatically. Guided evening trips run from Tonder and Ribe in season with guides who know which reed beds are being used, since the roost moves.

What you actually see

• Massing starlings at dusk - several hundred thousand birds moving as one.
• The reed bed roosts - the beds the birds drop into after the display.
• Raptors in the flock - the hawks that tighten the murmuration.
• The marsh at evening - flat reclaimed land under a wide sky.

When to go

Mid-March to mid-April and mid-September to mid-October, in the hour before dark. An evening. Guided trips book out in peak weeks. Calm dry evenings give the longest displays.

Honest expectations

It does not happen every night and the roost site moves, so going without a guide often means missing it entirely. Cold, wind and mosquitoes are all factors. Displays can be brief. Numbers vary enormously between years and evenings.

Nearby

Tonder is the southern base; Ribe is north and runs its own trips.