David Fleetham / Great white shark (Carcharodon carcharias) dorsal fin visible on surface. Guadalupe Island, Mexico.

Tony Wu / Indo-Pacific sailfish (Istiophorus platypterus) in feeding frenzy, with the remains of a previously large school of sardines (Sardina sp) in background. Isla Mujeres, Cancun, Mexico.

SCOTLAND: The Big Picture / Pod of Bottlenose dolphins (Tursiops truncatus) surfacing just offshore, Black Isle, Scotland, UK, July.

Espen Bergersen / Killer whale / Orca (Orcinus orca) male surfacing at sunset, Kvaloya, Troms, Norway October

Tony Wu / Humpback whale (Megaptera novaeangliae) female with calf, pursued by males during heat run. Vava'u, Kingdom of Tonga. Pacific Ocean.

Jordi Chias / Split level view of Blue shark (Prionace glauca) at surface at sunset, Azores Islands, Portugal, Atlantic Ocean

Wild Wonders of Europe / Widstrand / Dorsal fin of Orca / Killer whale (Orcinus orca) surfacing, Senja, Troms County, Norway, Scandinavia, January. Cetaceans are attracted to this area to feed on the large numbers of spawning Herring fis...

Brent Stephenson / Type B Killer whale (Orca orcinus) surfacing, close-up, Antarctic Sound, Antarctic Peninsula, Antarctic, January.

Ben Hall / Orcas (Orcinus orca) pair in sea surrounded by mountains, Iceland, January.

Hiroya Minakuchi / Orca (Orcinus orca) pod surfacing, Prince William Sound, Alaska

Hiroya Minakuchi / Orca (Orcinus orca) pod surfacing, Hokkaido, Japan

Richard Robinson / Hector's dolphin (Cephalorhynchus hectori) Akaroa Harbour, South Island, New Zealand, November. Editorial use only.