Globally significant fisheries take place in the seas surrounding the Arctic Ocean. The pollock fisheries in the Bering Sea and the cod fisheries in the Barents Sea are among the largest in the world. Large fish stocks require large feeding areas. Global warming has brought warmer waters and reduced ice cover in the Arctic, facilitating the northwards extension of fish stocks such as capelin and cod. This has brought speculations that commercial fisheries might develop in the Central Arctic Ocean.