Breaching (humpback whale): Breaching is the act of propelling the body upward until at least 40 per cent of it is clear of the water. Researchers arent sure why cetaceans breach; it could be an act of aggression, or just fun.

False killer whales: False killer whales are typically seen in family groups moving rapidly along the surface with their heads and upper bodies raised clear of the water. Pod sizes of several hundred are not uncommon, although groups of 10 to 20 are most frequent.

Gray whale: Gray whales are one of the most energetic large whales, frequently engaging in spyhopping and breaching.

Humpback fluke.

Sperm whale: This species is renowned for diving to tremendous depths and regularly remains submerged for over an hour. These energy-sapping dives are often followed by lengthy recuperation periods when the whale lies motionless at the surface.

Killer whale (or orca): Despite its name, the killer whale is in fact the largest of the dolphins, and perhaps the most striking and familiar of all cetaceans. Killer whales are often very active at the surface, where they are frequently observed breaching, spyhopping and flipper slapping.

Bow riding (common bottlenose dolphins): Swimming in the pressure wave created ahead of large objects pushing through the water such as whales or ships. This behavior, a specialty of most dolphins, is useful in assisting with identification as some species and populations are more keen to ride the bow than others.

Clockwise from top-right: spyhopping killer whales, Pacific white-sided dolphin, bottlenose dolphins.