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
Cetacea radiation. This shrinks the food supply for many marine animals, but the filter-feeding baleen whales are most impacted. Even the Nekton is, in addition to intensive exploitation, damaged by the radiation. Food supplies are also reduced long-term by ocean acidification due to increased absorption of increased atmospheric carbon dioxide. The CO reacts with water to form carbonic acid, which reduces the construction of the calcium carbonate skeletons of food supplies for zooplankton that baleen whales depend on. The military and resource extraction industries operate strong sonar and blasting operations. Marine seismic surveys use loud, low-frequency sound that show what is