Whales roam throughout all of the world’s oceans, communicating with complex and mysterious sounds. the blue whale can reach lengths of more than 100 feet and weigh up to 200 tons—as much as 33 elephants. Despite living in the water, whales breathe air. they are warm-blooded mammals who nurse their young. A thick layer of fat called blubber insulates them from cold ocean waters. Whales are at the top of the food chain and have an important role in the overall health of the marine environment. Whales play a significant role in capturing carbon from the atmosphere.