Whales are mammals that belong in the Cetacea order, alongside dolphins and porpoises. There are two sub-orders of whales: baleen and toothed whales. The baleen whales get the name from the comb-link fringe on their upper jaw. This fringe, called baleen, is designed for filtering plankton and other small fish and crustaceans that may pass through. Passive feeders such as these include blue whales and grey whales. Toothed whales possess normal teeth made of bone, used for consuming fish and squid, and sometimes other whales, marine mammals such as seals, and birds such as penguins. More active hunters usually than baleen whales, killer whales and beluga whales are a few examples of toothed whales. Whales are streamlined in form, with paddle-shaped forelimbs or flippers and a long tail split in two horizontally at the end. Their tail end is called a fluke, and it helps to propel the whale through the water. Some, but not all whales, may have a dorsal fin on their back.
Whales navigate through the use of echolocation. They can be found in every ocean, but the range differs between species. Because whales are mammals, they possess lungs to breathe air. They can remain submerged mostly at the surface while breathing through a blowhole located on the top of their head. Baleen whales have two blowholes, while toothed whales only have one. They are also warm-blooded and provide milk for their young to feed off of. A whale’s gestation period can take anywhere between 9 to 15 months, producing only 1 offspring upon giving birth. The nursing period is long and baby whales form a close bond with their mother. Many whales will feed in colder waters and migrate long distances to warmer waters for annually during the breeding season, especially baleen whales. Depending on the species, a whale may migrate alone or in a group known as a pod. Toothed whales are often in pods when migrating, hunting, and raising their young.
Whale watching is a popular activity for tourists looking to catch a glimpse of these massive, and rather active, marine mammals. Many whales, even the largest ones, have the capacity to jump high or breach the surface of the water. Whales can communicate with each other by splashing their flukes, which may possibly be a signal for danger, and singing to one another. Whales do need to sleep, but they must be careful not to remain unconscious for extended periods since they need air to breath. Many whale species can be found on the endangered species list because of threats such as pollution, sonar testing, whaling practices and sea level rise and temperate changes caused by climate change. Whaling practices in particular are the biggest issue. While the International Whaling Commission has prohibited the hunting of these species, countries like Norway, Iceland, and Japan still continue their activities.