Baleen whales are a group of large marine mammals known for their unique feeding system. Instead of teeth, they have baleen plates made of keratin, which they use to filter small fish and plankton from the water. This allows them to consume large amounts of food efficiently while swimming. These whales are among the largest animals on Earth, with species like the blue whale reaching lengths of up to 100 feet. Baleen whales are typically found in oceans around the world and are known for their long migrations between feeding and breeding grounds.