Espen Bergersen / Long-finned pilot whale (Globicephala melas). Kvaloya, Norway.

Espen Bergersen / Gulls and Killer whales / orcas (Orcinus orca) feeding on herring. Kvaloya, Troms, Norway October

Espen Bergersen / Killer whale / orca (Orcinus orca) male. Kvaloya, Troms, Norway October

Espen Bergersen / Humpback whales (Megaptera novaeangliae). Kvanangen, Troms, Norway. November

Espen Bergersen / Killer whales / orcas (Orcinus orca). Spyhopping. Kvaloya, Troms, Norway November

Tony Wu / Humpback whale (Megaptera novaeangliae australis) male calf playing at ocean surface after coming up to breathe. Vava'u Islands, Tonga.

Tony Wu / Humpback whale (Megaptera novaeangliae) lying on its side while executing a series of pectoral fin slaps on ocean surface. Vava'u, Tonga, South Pacific.

Nick Hawkins / Galapagos green turtle (Chelonia mydas agassizi) swimming above sea floor with shoal of fish in background. Off San Cristobal Island, Galapagos.

David Fleetham / Humpback whale (Megaptera novaeangliae), mother and calf swimming just below surface in front of the West Maui Mountains. South of Lahaina, West Maui, Hawaii.

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.

Jack Dykinga / Eroded salt laden sandstone 'fins' in incredible sculpted forms comprise an area know as 'Little Finland.' Gold Butte National Monument, Nevada, USA. President Barack Obama designated the monument on...

Jack Dykinga / Eroded salt laden sandstone 'fins' in incredible sculpted forms comprise an area know as 'Little Finland.' Gold Butte National Monument, Nevada, USA. President Barack Obama designated the monument on...

Jack Dykinga / Eroded salt laden sandstone 'fins' in incredible sculpted forms comprise an area know as 'Little Finland.' Gold Butte National Monument, Nevada, USA. President Barack Obama designated the monument on...

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.

Claudio Contreras / Whale shark (Rhincodon typus) feeding view of tail, Isla Mujeres, Caribbean Sea, Mexico, August. Vulnerable species.

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

Richard Robinson / Blue shark (Prionace glauca) worked from below with rays of sun, off the coast of Hawke's Bay, New Zealand, February.

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

Gabriel Rojo / Southern Right whale (Eubalaena australis) breaching, Peninsula Valdes, Chubut, Patagonia, Argentina.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) juvenile on beach, Galapagos

Floris van Breugel / Black and white photograph of humpback whale (Megaptera novaeangliae) tail slapping at surface, Glacier Bay National Park, Alaska, USA, August 2014.

Espen Bergersen / Humpback whale (Megaptera novaeangliae) with fin above water, Andfjorden close to Andoya, Nordland, Northern Norway. January.

Espen Bergersen / Humpback whales (Megaptera novaeangliae) and Killer whale (Orcinus orca) feeding on a bait ball of Herring. Andfjorden close to Andoya, Nordland, Northern Norway. January.

Fred Olivier / Adelie penguins (Pygoscelis adeliae) wide angle portrait of two with larger group in background, Antarctica.

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

Pascal Kobeh / Group of California sea lions (Zalophus californianus) in a kelp forest (Macrocystis pyrifera), California, USA. Pacific ocean.

Ben Cranke / Fin whale (Balaenoptera physalus) surfacing with mountain landscape, Liefdefjorden, Svalbard, Norway. July 2011.

Alex Mustard / Portrait of male Scalefin anthias (Pseudanthias squamipinnis) swimming in open water, to feed on plankton. Ras Katy, Sinai, Egypt. Gulf of Aqaba, Red Sea.

Roy Mangersnes / Bearded seal (Erignathus barbatus) stretching flipper, on an ice floe, Spitsbergen, Svalbard, Norway, July.

Gabriel Rojo / Orca (Orcinus orca) baby age 10 days, swimming with his mother. Punta Norte Natural Reserve, Peninsula Valdes, Chubut Province, Patagonia Argentina

Andy Trowbridge / Grey Seal (Halichoerus grypus) at rest on submerged rock, head and one flipper above water. Shetland Islands, Scotland, UK. July.

Nick Upton / Grey seal (Halichoerus grypus) pup resting on a sandy beach, stretching and rubbing its head with its flipper, Norfolk, England, UK, January.

Chris & Monique Fallows / Orca male (Orcinus orca) raising pectoral flipper out of the water, Prince William Sound, Alaska, USA.

Chris & Monique Fallows / Indo Pacific Sailfish (Istiophorus platypterus) feeding on sardines, Isla Mujeres, Mexico.

Chris & Monique Fallows / Split level shot of Great white shark (Carcharodon carcharias) fin above the water and leisure boat in the background, with Seal Island, False Bay, South Africa.

Jeff Rotman / Pectoral fin of a Steepheaded parrotfish (Chlororus gibbus) in the Red Sea, Egypt.

Cheryl-Samantha Owen / Southern Rockhopper penguin (Eudyptes chrysocome) tame bird 'Rocky' used for educational purposes, Southern African Foundation for the Conservation of Coastal Birds (SANCCOB), Cape Town, South Africa....

Alex Mustard,Alex Mustard / A signal blenny (Emblemaria hypacanthus) displays its showy dorsal fin as it extends out of its tube home. La Paz, Mexico. Sea Of Cortez, East Pacific Ocean.

Ben Hall / Orcas (Orcinus orca) pod feeding on herring, wide shot showing surrounding landscape, Iceland, January 2013

Denis-Huot / Killer whales (Orcinus orca) off the coast of British Columbia, North Pacific Ocean

Steven Kazlowski / Killer whale (Orcinus orca) large pod with one male approaching, in Kenai Fjords National Park, Chiswell Islands National Marine Sanctuary, South Central Alaska, USA

Alex Mustard / Basking shark (Cetorhinus maximus) rear view of shark feeding at the surface on plankton, Cairns Of Coll, Isle of Coll, Inner Hebrides, Scotland, UK, North East Atlantic Ocean, June

Jeff Rotman / Common Thresher Shark (Alopias vulpinus) caught on gill net being hauled up onto boat, Huatabampo, Mexico, Sea of Cortez, Pacific Ocean. Model released. Model released.