Expedition Uncovers Intricate Geometric Fish Nests in Antarctica's Weddell Sea

In January 2019, researchers set out on an expedition to the Weddell Sea in Antarctica to search for the wreckage of the HMS Endurance, a ship that became trapped and destroyed by ice in 1915. While they were unable to locate the wreck, the expedition made an unexpected discovery: the seafloor of the Weddell Sea was covered in striking geometric patterns created by fish.

The expedition's remotely operated underwater vehicle, nicknamed Lassie, captured footage of over 1,000 nests built by a species of rockcod fish called yellowfin notie. These nests were arranged in distinct shapes, including clusters, crescents, straight lines, ovals, and U-shapes. The researchers believe these patterns represent a strategy by the fish to protect their eggs from predators like ribbon worms.

The expedition was able to explore the Weddell Sea seafloor after the massive A68 iceberg calved from the Larsen C Ice Shelf in 2017, exposing the previously hidden area. Scientists are now petitioning for the Weddell Sea's fragile ecosystem to be protected, as it faces rapid climate change. The discovery of the complex fish nesting behavior is a testament to the diversity of life that still remains to be uncovered in this remote and challenging environment.