The Black Sun of Denmark
In spring and autumn, at sunset over the Danish marshes, the sky goes dark as a million birds swirl together in vast, shifting shapes.
What was reported
In the marshes of south-western Jutland, near the border with Germany, huge flocks of migrating starlings gather in spring and autumn. At dusk they rise together and wheel across the sky in great clouds, folding and stretching like smoke, before dropping into the reedbeds to roost.
With up to a million birds, they can blot out the setting Sun. The Danes call it sort sol, 'black sun'.
Explanations offered
Starlings gather in murmurations to protect themselves from hawks and falcons: each bird follows its nearest neighbours, and the whole flock moves as one. How they coordinate so quickly is still studied by scientists.
- When
- Every spring and autumn
- Where
- Tønder marshes, Southern Denmark, Denmark
- Witnesses
- Thousands of visitors each year
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.
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