TechMysterious North Sea holes: Porpoises involved

Mysterious North Sea holes: Porpoises involved

Images source: © Wikimedia Commons | Marcus Wernicke (Tuugaalik), Porpoise Conservation Society (

6:11 AM EST, February 28, 2024

In the shallow waters of the North Sea, millions of round or oval-shaped holes are found, varying in width up to 197 feet and about 4.3 inches deep. According to Live Science, these formations connect, forming larger structures which, in places, resemble Venn diagrams. Earlier theories attributed their presence to methane gas escaping from the seabed.

Mysterious holes at the bottom of the North Sea

Recent studies, as reported in the "Communications Earth & Environment" journal, propose a novel explanation. Porpoises, not methane, frequenting this part of the sea, are likely the architects behind these holes. These mammals burrow in the seabed while foraging, suggesting that they, along with other large sea creatures, significantly influence the seabed's landscape.

Jens Schneider von Deimling, a geologist from the University of Kiel, was initially skeptical of the methane hypothesis. To test its accuracy, he led an expedition in the North Sea, using advanced equipment, including a special echosounder, to map the seabed and its shallow waters in detail. Their analysis showed no links to methane emissions.

The quest to demystify the North Sea's seabed did not end there. Researchers employed a multibeam echosounder, noted for its high-resolution seabed imaging capabilities, as highlighted by Live Science. This technology enabled the team to examine the depressions precisely, debunking the theory of methane-related conical shapes. The breakthrough came after consulting biologists and porpoise experts, casting new light on the phenomenon.

Further investigations involved modeling habitats for eels and porpoises, overlaying this data with oceanographic information, such as currents. Findings revealed that these habitats overlapped significantly with the studied areas. Echo-sounding data corroborated their hypothesis: regions predicted to host porpoises and similar species coincided with a higher density of holes. The scientists deduced that the larger holes might be cavities formed by sea currents, areas frequented by porpoises. They are optimistic about obtaining photographic proof of porpoises actively creating these seabed holes in the near future.

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