Whales: Common Behaviour
The most common whale to breach is the Humpback whale (seen left). Breaching is actually a quite mysterious act. Basically, breaching occurs when a whale pushes its body out of the water in an acrobatic-like movement. Then, it splashes back into the water, most commonly on its back!
Most scientists speculate that breaching occurs as a result of a whale attempting to get barnacles off its body - the younger calves (baby whales) will mimic the adults, playing and learning (sound familiar?). Most commonly, whales breach half of their bodies out of the water. However, breaches can consist of full body exits, as well!
Blowing occurs when a whale comes up to the surface of the water to let its air out (exhales) and back in again (inhales). This is obviously a common occurence as whales are mammals that need to breath oxygen. Thus, what comes out of a whale's blowhole is a mixture of hydrogen and oxygen! Once a whale is ready to descend back under the water, it will close its blowhole and fluke (described below).
The purpose of fluking is for deep-sea diving. All whales, especially large baleen whales, fluke. A whale will thrust its tail out of the water in order to gain more momentum for deep dives - much like the way in which a human thrusts his or her feet out of the water in order to dive to the bottom of a swimming pool! For humans, these dives can only last a few minutes (if that), but for whales, deep sea dives usually last up to 30 minutes (90 minutes for Sperm whales, who are the longest-time diving whales).