Jellyfish swarm Danish coasts in rare numbers

Unusually large swarms of jellyfish have washed up along Danish shores, with beaches in northern Jutland, including Hou, reporting dense clusters of the slimy creatures, DR reports.

The surge is driven by a combination of warm water, favourable wind patterns, and the lowest Baltic Sea water levels in 140 years, creating ideal conditions for the jellyfish.

Hou harbour master Åge Johansen said the numbers are striking. “It’s intense when they arrive in these swarms. I haven’t seen this many jellyfish since I was a child,” he told DR.

The phenomenon is not limited to Hou, with similar reports emerging from other coastal areas. Additionally, the American comb jelly, also known as the sea walnut, has been spotted along Danish shores, though it poses no threat to humans.