Scientists have found what is thought to be the world’s largest fish breeding area beneath Antarctic ice. Estimates run as high as 60 million for the number of active ice fish breeding nests found.
The nests are neatly spaced and guarded by an adult fish watching over an estimated 2100 eggs per nest. 60 million is a guess based on counting the number of nests observed and extrapolating. Discovery of the nest site is fueling efforts to place controls on fishing in the area to help protect the ecosystem.
This breeding ground is in Antarctica and was discovered by accident. Researchers studying sea life discovered massive numbers of nests of ice fish. The research vessel Rv Polarstern was breaking through the ice and dragging cameras and other equipment along the bottom and found the nests. Rv Polarstern is operated by the Alfred Wegener Institute. The ship is a key research unit of the institute, which conducts ocean research in frigid Arctic and Antarctic waters. The institute is named after Alfred Wegener. Wegener was a scientist who first proposed the Continental Drift theory in 1912.
The approximately 33 members of the Channichthyidae (ice fish) family have some highly unusual characteristics.
Icefish have heads that resemble crocodiles, leading them to be called crocodile ice fish. These fish swim in water that can be 28 degrees fahrenheit, but do not freeze. They have antifreeze proteins in their blood. The fish lack hemoglobin so the exact mechanism of oxygen transfer is not fully understood. Since they do not have scales and live in oxygen rich water some oxygen transfer may occur on the skin surface. They have large hearts which may allow for sufficient oxygen transfer. Their bones are less dense and lighter than those of many other fish. They also lack swim bladders common among bony fish to control buoyancy. The bladders allow the fish to stay at one level without having to waste energy moving up and down.
Icefish were discovered in 1927. Since then theyhave been the subject of study due to their unusual characteristics. For example, their light, mineral poor bones as studied for insights into human osteoporosis.
The nests were discovered in the Weddell Sea about one million square miles in size. It is a bay off the Antarctic coast. The sea is named after James Weddell an explorer and seal hunter who traversed it in 1823,