Researchers unearthed a surprising seafloor discovery: a highly organized city of fish nests with striking geometric patterns in a remote part of the Western Weddell Sea, an area that had been covered by a thick ice shelf for centuries.
The seafloor has once been concealed by a thick ice shelf, but that changed in 2017 when the massive A68 iceberg calved from the Larsen C Ice Shelf.
However, the iceberg measured 2,239 square miles, about the size of Delaware.
For that purpose, researchers conducted this study to explore the biology of the western Weddell Sea and to search for the wreck of the HMS Endurance which became trapped and cracked by ice in 1915.
In this connection, senior lecturer in the School of Life Sciences at the UK’s University of Essex, Dr. Michelle Taylor said, “The sea ice in particular was a challenge as at the time there was a bottleneck and a buildup of sea ice around that area.”
On the contrary, the wreckage was not found, but the voyage captured crucial underwater footage of marine life dwelling in the frigid depths of the Weddell Sea-a vulnerable ecosystem that needs to be protected by law.
While Lassie passed over the Weddell seafloor, large concavities appeared in the sand; the round spots were noticeably clean compared to their surroundings, which were littered with the decomposing remains of organisms.
The video footage helped scientists to observe the fish and fish larvae within the dimples that Lassie recorded.
While a closer look helps to reveal the fish to be a species of rockcod called Lindbergichthys nudifrons known as the yellowfin notie.
The researchers also found the 1,036 active nests located across five sites on the seafloor showing six distinctive patterns.
The study further revealed that the individual and isolated nests are commonly larger than any arranged in a particular shape.
The results demonstrated that the patterns represent a strategy for survival against predators.
While the fish on the outside of the clutter patterns, the fish at the center receive the most protection from predators.
The researchers observed that this arrangement represents the “selfish herd theory” where individuals mitigate the domain of danger by specifically putting other individuals between themselves and an approaching predator.
Nonetheless, the research study provides crucial evidence of breeding habitats, strengthening the idea of the Weddell Sea Marine Protected Area, and highlights a surprising seafloor discovery with significant conservation implications.
