Digestive system of humpback whales Digestive system of humpback whales The digestive system of humpback whales ("Megaptera novaeangliae") is adapted to digest tiny crustaceans such as krill, plankton, and small fish (including herring and mackerel) which the whale filters from the ocean using its baleen, a sieve-like structure in the upper jaw. Humpback whales belong to the parvorder baleen whales, which are carnivorous, seasonal feeders. The baleen, a sieve-like structure in the upper jaw made of keratin, is used to filter plankton, among other food sources, from the water. Ventral grooves are expandable concave furrows that line a whale's throat and have the peculiarity of
Baleen whale Baleen whales are K-strategists, meaning they raise one calf at a time, have a long life-expectancy, and a low infant mortality rate. Some 19th century harpoons found in harvested bowheads indicate this species can live more than 100 years. Baleen whales are promiscuous, with none showing pair bonds. They are polygynous, in that a male may mate with more than one female. The scars on male whales suggest they fight for the right to mate with females during breeding season, somewhat similar to lek mating. Baleen whales have fibroelastic (connective tissue) penises, similar to those of artiodactyls. The tip of