Digestive system of humpback whales stretching like an accordion. They allow whales to open their mandible to 90 degrees to gulp water and prey. They expel saltwater through the baleen plates, leaving behind krill and plankton. The whale's tongue plays a vital role in filter feeding, as it is used to push the water out of its mouth while keeping the prey trapped in its baleen bristles. As humpback whales do not have teeth, their food is swallowed whole and travels down the esophagus into the preliminary stomach (known as the forestomach) to be ground. Baleen whales have a multi-chambered stomach, divided into three distinct
Baleen whale minke whales, catching nearly 7,000; to a far lesser extent, they also caught fin whales. Animal-rights activist groups, such as the Greenpeace, object to Japan's scientific whaling, with some calling it a substitute for commercial whaling. In 2014, the International Court of Justice (the UN judicial branch) banned the taking of whales for any purpose in the Southern Ocean Whale Sanctuary; however, Japan refuses to stop whaling and has only promised to cut their annual catches by a third (around 300 whales per year). Baleen whales can also be affected by humans in more indirect ways. For species like the