As a whole the cetacean family is composed of around 80 – 90 species of whale, dolphin and porpoise and is divided into two suborders depending on the marine mammals characteristics.
Baleen whales make up one of two whale suborders within the cetacean family.
The other is the toothed whale suborder which also includes all species of dolphin and porpoise.
Most baleen whales are significantly larger in size when compared to the toothed whale species with the blue whale (the largest of the baleen whales) reaching lengths in excess of 100 ft.
Unlike their toothed whale cousins baleen whales are born with baleen plates instead of teeth.
Due to the absence of teeth baleen whales hunt for their food differently than toothed whales.
In fact many species of baleen whale hunt for food using a method known as filter feeding.
These whales capture their food by swimming towards their prey with their mouth open and use their baleen bristles to filter large amounts of fish, krill, shrimp, octopus, various crustaceans and other sea sediments from the water.
They then expel the water out of their mouth (often using their tongue) while leaving their prey stuck in the baleen bristles.
The bristles, which are attached to the baleen plates, are often said to resemble the teeth found on a comb and are spaced far apart enough to allow water to escape, while preventing prey from getting out.
Some baleen whales will also hunt for bigger prey such as large fish, squid or octopus, but most prefer smaller sources of food due to their lack of teeth and small throats.
In terms of social structure baleen whales are known to be quite solitary in nature often traveling alone or in small groups.
Larger pods or groups may form during migration, feeding or breeding periods and reduce in size once they finish interacting with one another.
Communication among baleen whales involves loud low-pitched moans and whines, and physical gestures such as spy hopping, lob tailing, breaching and charging.
Lastly, because baleen whales are quite large in size their large mass and thick blubber allows them to be very efficient at maintaining body heat in cold climates which allows various species to travel, live and thrive in extremely cold climates.