Mark Brownlow / Sperm whale {Physeter macrocephalus} diving, tail fluke, Kaikoura, South Island, New Zealand

Jordi Chias / Humpback whale (Megaptera novaeangliae) fluke Antarctic Peninsula, Antarctica.

Jordi Chias / Humpback whale (Megaptera novaeangliae) diving, tail fluke, Antarctic Peninsula, Antarctica.

Shane Gross / Larval flounder (possibly Laeops Kitahara) in the open ocean at night off Anilao, Philippines.

Espen Bergersen / Humpback whales (Megaptera novaeangliae) showing tail fluke when they dive. Kvanangen, Troms, Norway. December

Espen Bergersen / Humpback whale (Megaptera novaeangliae) diving. In background a diving boat and 3 divers visible in the water. Kvanangen, Troms, Norway. November

Espen Bergersen / Sperm whale {Physeter macrocephalus} showint tail fluke as it dives. Photographed just before midnight. 22 nautical miles northwest of Andenes, Northern Norway. July

Espen Bergersen / Humpback whale (Megaptera novaeangliae) showing tail fluke as it dives. Kvanangen, Troms, Norway. November

Espen Bergersen / Killer whale / orca (Orcinus orca) splashing with tail fluke. Kvaloya, Troms, Norway October Sequence 4 of 7

Espen Bergersen / Humpback whale (Megaptera novaeangliae) showing tail fluke as it dives. Kvanangen, Troms, Norway. December

Nick Hawkins / North Atlantic right whale (Eubalaena glacialis) tail fluke, diving to feed in the Gulf of Saint Lawrence, Canada. Endangered species. July

Espen Bergersen / Aerial shot of a Humpback whale (Megaptera novaeangliae) diving and showing tail fluke, Troms, Norway, January.

Espen Bergersen / Aerial shot of a female Humpback whale (Megaptera novaeangliae) and calf surrounded by Killer whales (Orcinus orca), mother hits sideways with her tail fluke to drive Killer whales away, Skjervoy, Tro...

Flip Nicklin / Humpback Whale (Megaptera novaeangliae) tail slapping at sunrise, Lahaina, Maui, Hawaii

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) sailing at sunset, Peninsula Valdez, Argentina

Juergen Freund / Slow motion aerial shot of a Pygmy blue whale (Balaenoptera musculus brevicauda) blowing / breathing at the surface before diving, Banda Sea, Indonesia.

Claudio Contreras / Grey whale (Eschrichtius robustus) tail, San Ignacio Lagoon, El Vizcaino Biosphere Reserve, Baja California, Mexico, March

Franco Banfi / Sperm whale (Physeter macrocephalus) tail below water as whale surfaces, Dominica, Caribbean Sea, Atlantic Ocean, Vulnerable species.

Sue Daly / Close up of a Plaice (Pleuronectes platessa), swims away, Sark, British Channel Islands, UK, June.

Espen Bergersen / Sperm whale (Physeter macrocephalus) tail fluke visible as whale dives. outside Andoya, Norway March

Tony Wu / Humpback whale (Megaptera novaeangliae) executing a dramatic tail slap, throwing up a cascade of water with its powerful fluke, Vava'u, Tonga, South Pacific

Tony Wu / Humpback whales (Megaptera novaeangliae) unusual scene with two adults tail-slapping together in rough seas, Vava'u, Tonga, South Pacific

Tony Wu / Humpback whale (Megaptera novaeangliae) rear view, taken while the whale was staying still and singing. Hunga Channel. Vava'u, Kingdom of Tonga, Pacific Ocean.

Tony Wu / Humpback whale (Megaptera novaeangliae) males tail fluke, Vava'u, Tonga, Pacific Ocean.

Tony Wu / Humpback whale (Megaptera novaeangliae), fluke of female with male calf playing below, Vava'u, Tonga, Pacific Ocean.

Wild Wonders of Europe / Widstrand / Humpback whale (Megaptera novaeangliae) tail fluke above water before diving, Senja, Troms County, Norway, Scandinavia, January. Cetaceans are attracted to this area to feed on the large numbers of sp...

Wild Wonders of Europe / Widstrand / Humpback whale (Megaptera novaeangliae) tail fluke above water before diving, Senja, Troms County, Norway, Scandinavia, January. Cetaceans are attracted to this area to feed on the large numbers of sp...

Espen Bergersen / Fluke of diving Humpback whale (Megaptera novaeangliae) with full moon low on the horizon during polar night time, with blow from second whale in the background, Kvaloya, Troms, Northern Norway. Novem...

Jack Dykinga / Humpback whale (Megaptera novaeangliae) fluke marked with barnacle attachments, CONANP protected area, Baja Sur, Sea of Cortez, Mexico. February.

Ole Jorgen Liodden / Blue Whale (Balaenoptera musculus) tail fluke above water surface. Spitsbergen, Svalbard, August.

Juan Carlos Munoz / Southern right whale (Eubalaena australis / Balaena glacialis australis) flipping its tail out of the water. Valdes Peninsula, Patagonia, Argentina, Oct 2008

Mark Carwardine / Blue whale (Balaenoptera musculus) fluking / diving, Endangered species, Sea of Cortez, Baja California, Mexico

Mark Carwardine / Blue whale (Balaenoptera musculus) fluking / diving, Endangered species, Sea of Cortez, Baja California, Mexico

Wild Wonders of Europe / Lundgren / Sperm whale (Physeter macrocephalus) fluke with a whale watching boat in the distance, Pico, Azores, Portugal, June 2009

Wild Wonders of Europe / Jensen / Tail fluke of a diving Humpback whale (Megaptera novaeangliae) Disko Bay, Greenland, August 2009

Doug Perrine / Humpback whale thrashes water with tail fluke, Hawaii (taken under permit no 587)

Doug Perrine / Sperm whale {Physeter macrocephalus} raising tail fluke before diving. North Atlantic.

Colin Monteath / Humpback Whale (Megaptera novaeangliae) tail near iceberg, Antarctica

Colin Monteath / Humpback Whale (Megaptera novaeangliae) observed by tourists in a zodiac boat near Melchoir Island, Antarctic Peninsula, Antarctica

Flip Nicklin / Sperm Whale (Physeter macrocephalus) tail, New Zealand

Flip Nicklin / Sperm Whale (Physeter macrocephalus) tail, New Zealand

Flip Nicklin / Sperm Whale (Physeter macrocephalus) tail, New Zealand

Mark Jones / Blue Whale (Balaenoptera musculus) tail, Sea of Cortez, Baja California, Mexico

Mark Jones / Blue Whale (Balaenoptera musculus) tail, Sea of Cortez, Baja California, Mexico

Flip Nicklin / Sperm Whale (Physeter macrocephalus) tail, New Zealand

Flip Nicklin / Sperm Whale (Physeter macrocephalus) tail

Flip Nicklin / Sperm Whale (Physeter macrocephalus) tail, New Zealand

Flip Nicklin / Gray Whale (Eschrichtius robustus) portrait of back as it skims surface of water, Clayoquot Sound, Vancouver Island, British Columbia, Canada

Flip Nicklin / Southern Right Whale (Eubalaena australis) tail, Peninsula Valdez, Argentina

Flip Nicklin / Blue Whale (Balaenoptera musculus) tail, Sea of Cortez, Mexico

Flip Nicklin / Blue Whale (Balaenoptera musculus) and researchers, Sea of Cortez, Mexico

Flip Nicklin / Blue Whale (Balaenoptera musculus) tail, Sea of Cortez, Mexico

Doug Perrine / Tail fluke of diving Sperm whale {Physester macrocephalus} North Atlantic Ocean (Non-ex).

Todd Pusser / Tail fluke of diving Sperm whale {Physeter macrocephalus} Kaikoura, New Zealand, Pacific

Espen Bergersen / Humpback whales (Megaptera novaeangliae) tail fluke Troms, Norway.

Espen Bergersen / Killer whales / orcas (Orcinus orca) at surface, slapping tail fluke, Norway. November.

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

Espen Bergersen / Killer whales / orcas (Orcinus orca) fluke at surface, Troms, Norway. November.

Espen Bergersen / Killer whale / orca (Orcinus orca) splashing with tail fluke. Kvaloya, Troms, Norway. Sequence 1 of 7 November.

Sergio Hanquet / Short-finned pilot whale (Globicephala macrorhynchus) fluke on surface, whale diving. Tenerife, Canary Islands.

Tony Wu / Humpback whale (Megaptera novaeangliae australis) female with calf swimming above head. Rake marks on fluke created by Orca or False Killer whale predators. Vava'u Islands, Tonga.

Andy Rouse / Humpback whale (Megaptera novaeangliae) fluke at sunrise, Svalbard, Norway.

Andy Rouse / Humpback whale (Megaptera novaeangliae) tail fluke in distance, Svalbard, Norway, July.

Gabriel Rojo / Orca (Orcinus orca) pod hunting Sealion, tossing it out of the sea, Punta Norte, Valdez Peninsula, Argentina. April.

Gary Bell/ Oceanwide / Humpback Whale (Megaptera novaeangliae) tail slapping, Coffs Harbor, Solitary Islands Marine Park, New South Wales, Australia

Nick Hawkins / North Atlantic right whale (Eubalaena glacialis) struggling to free itself from entanglement in fishing gear, showing wounds on tail fluke, Gulf of Saint Lawrence, Canada. August.

Jordi Chias / Humpback whale (Megaptera novaeangliae) fluke Antarctic Peninsula, Antarctica.

Tony Wu / Water streaming off of a diving Humpback whale's (Megaptera novaeangliae) fluke, with 42ft Nordic Tug Legend visible in the background. Chantham Strait, Alaska, USA.

Shane Gross / Larval flounder (possibly Laeops Kitahara) in the open ocean at night off Anilao, Philippines.

Espen Bergersen / Humpback whale (Megaptera novaeangliae) showing tail fluke as it dives. Kvanangen, Troms, Norway. December

Espen Bergersen / Sperm whale {Physeter macrocephalus} showint tail fluke as it dives, at midnight, Northern Norway. July

Espen Bergersen / Killer whale / orcas (Orcinus orca) splashing with tail fluke. Kvaloya, Troms, Norway October

Espen Bergersen / Killer whale / orca (Orcinus orca) splashing with tail fluke. Kvaloya, Troms, Norway October Sequence 6 of 7

Espen Bergersen / Killer whale / orca (Orcinus orca) splashing with tail fluke. Kvaloya, Troms, Norway October Sequence 3 of 7

Espen Bergersen / Killer whale / orca (Orcinus orca) splashing with tail fluke. Kvaloya, Troms, Norway October Sequence 2 of 7.

Espen Bergersen / Killer whale / orca (Orcinus orca) splashing with tail fluke. Kvaloya, Troms, Norway October Sequence 5 of 7

Espen Bergersen / Aerial shot of three Humpback whales (Megaptera novaeangliae) socialising, Troms, Norway, January.

Espen Bergersen / Aerial shot of a Humpback whale (Megaptera novaeangliae) diving and showing tail flukes, Troms, Norway, January.

Espen Bergersen / Aerial shot of a Humpback whale (Megaptera novaeangliae) diving, Troms, Norway, January.

Espen Bergersen / Aerial shot of two Humpback whales (Megaptera novaeangliae) breathing at surface, one dives, Troms, Norway, January.

Espen Bergersen / Aerial shot of a Humpback whale (Megaptera novaeangliae) surfacing to breathe, before diving again, Troms, Norway, November.

Flip Nicklin / Humpback Whale (Megaptera novaeangliae) breaching near shore, Lahaina, Maui, Hawaii

Flip Nicklin / Humpback Whale (Megaptera novaeangliae) diving near coast, Maui, Hawaii

Mark Carwardine / Humpback whale (Megaptera novaeangliae) tail fluke above water about to dive with whale watching boat behind, Bay of Fundy, New Brunswick, Canada

Doc White / Humpback whale (Megaptera novaeangliae) fluke slapping. Southeast Alaska, USA. July.

Doc White / Humpback whale (Megaptera novaeangliae) fluke slapping in coastal waters. Southeast Alaska, USA. July.

Doc White / Humpback whale (Megaptera novaeangliae) fluke slapping in coastal waters. Southeast Alaska, USA. July.

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) diving, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) sailing at sunset, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) sailing at sunset, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) pair surfacing and sailing, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) sailing at sunset, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) sailing at sunset, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) sailing, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) pair sailing and surfacing at sunset, Peninsula Valdez, Argentina

Hiroya Minakuchi / Southern Right Whale (Eubalaena australis) sailing, Peninsula Valdez, Argentina