Breaching is a behavior exhibited by whales where they propel their entire body out of the water, exposing up to 90% of their body above the surface. Breaching is a genuine jump with an intent to clear the water, and it is believed to be a display of strength and power, serving as a territorial claim. Whales showcase their physical prowess and send a clear message to other individuals or competing pods that the area they occupy is their territory. Breaching is also believed to be a way for whales to communicate with others in their pod, as the powerful splash and sound created by breaching can travel vast distances underwater.

Whales use two techniques to breach. The first method, most common in sperm and humpback whales, is conducted by swimming vertically upwards from depth and heading straight out of the water. The other more common method is to travel close to the surface and parallel to it, and then jerk upwards at full speed with as few as 3 tail strokes to perform a breach.

Breaching is a sign that the animal is physically fit enough to afford energy for this acrobatic display, hence it could be used for ascertaining dominance, courting, or warning of danger. It is also possible that the loud "smack" upon re-entering is useful for stunning or scaring prey, similar to lobtailing.

In summary, breaching is a behavior exhibited by whales where they propel their entire body out of the water, and it is believed to be a display of strength and power, serving as a territorial claim, and a way for whales to communicate with others in their pod.