E. Disease and parasites. As in any animal population, a variety of diseases can be responsible for baleen whale deaths. Many types of external and internal parasites are common to baleen whales. Baleen plates can be infested by copepods, nematodes, and protozoans. A parasitic copepod attaches in the blubber layer.
Diatoms grow on the skin of some species, including the blue whale.
This creates an olive-colored film on the skin surface. Some species such as gray and humpback whales are heavily infested by external parasites. Barnacles feed on plankton in the water. Whale lice feed on whale skin and damaged tissue such as a wound. F. Entrapment in ice.