Explore the lives of ocean mammals that must return to the surface to breathe.
Whales, dolphins, and porpoises belong to a group of marine mammals called cetaceans. Unlike fish, they breathe air with lungs, are warm-blooded, give birth to live young, and feed their babies milk.
Learn what makes whales and dolphins mammals instead of fish.
Learn MoreSee how some of Earth's largest animals filter tiny food from seawater.
Learn MoreMeet dolphins, sperm whales, orcas, and other toothed cetaceans.
Learn MoreDiscover how whales can remain underwater while still needing air.
Learn MoreExplore the clicks, whistles, and songs cetaceans use to communicate.
Learn MoreFollow whales on some of the longest migrations in the animal kingdom.
Learn MoreLearn how young whales and dolphins grow and learn from adults.
Learn MoreWhales and dolphins share several characteristics with land mammals. They breathe using lungs rather than gills and must surface for air. They are warm-blooded, and mothers nurse their calves with milk while the young grow.
Baleen whales do not have ordinary teeth as adults. Instead, plates of baleen hang from their upper jaws and act as filters. A whale can take in water filled with krill or small fish and then push the water back out while trapping food inside its mouth.
Toothed whales include sperm whales, dolphins, porpoises, and orcas. They use teeth to catch prey such as fish and squid. Many toothed whales also use echolocation, producing sounds and listening to returning echoes to investigate their surroundings.
Cetaceans breathe through one or two blowholes located on top of the head. Before diving they take in air, and special adaptations help their bodies use oxygen efficiently. Different species have very different diving abilities, with some making much deeper and longer dives than others.
Sound travels very well through water, making it especially useful in the ocean. Dolphins can communicate with whistles and clicks, while some whales produce powerful calls that travel great distances. Male humpback whales are famous for complex patterns of sound often called songs.
Some whale species migrate thousands of kilometers between seasonal habitats. They may spend warmer months feeding in productive colder waters and travel toward warmer regions to breed or give birth. Scientists track migrations using observations, photographs, tags, and acoustic recordings.
A baby whale or dolphin is called a calf. Mothers provide milk and protection, and young animals often spend long periods learning important behaviors. Some species form lasting social groups in which relatives cooperate, communicate, travel, and sometimes hunt together.