Markus Varesvuo / White-tailed Eagle (Haliaeetus albicilla) mobbed by common gull (Larus canus) Flatanger, Norway, July

Todd Mintz / Bar Jack (Caranx ruber) predating dense school of Scad fish / Horse mackerel (Trachurus trachurus) Bonaire, Dutch Caribbean.

Juergen Freund / Carrier / Sea urchin crab (Dorippe frascone) carrying a fire urchin as a deterrent to predators. Lembeh Strait, North Sulawesi, Indonesia

Juergen Freund / Clark's anemonefish / Yellowtail clownfish (Amphiprion clarkii) prreing out from anemone tentacles. Misool, Raja Ampat, West Papua, Indonesia.

Philippe Clement / Oosterscheldekering / Eastern Scheldt storm surge barrier, the largest of 13 dams designed to protect the Netherlands from flooding. Neeltje Jans, Netherlands, March 2010

David Woodfall / Building a sea wall to combat climate change and protect fishing village from flooding, Sundarbans, Bangladesh, June 2008

Wild Wonders of Europe / Zankl / Newly hatched Loggerhead turtle (Caretta caretta) with its front flippers pressed tight to the marginal scutes of its carapace to avoid predation, Dalyan Delta, Turkey, August 2009

Claudio Contreras / Balloon fish (Diodon holocanthus) with defensive spines, Puerto Morelos National Park, Caribbean Sea, Mexico, January

Jeff Rotman / Black Blotched Porcupinefish (Diodon liturosus) inflated swimming in open ocean. Sipadan Islands, South China Sea.

Niall Benvie / White tailed sea eagle mantling prey {Haliaeetus albicilla} Norway

Fred Bavendam / Leopard Sea Cucumber (Bohadschia argus) ejects a mass of long white sticky cuvierian tubules as a defense when disturbed, Manado, Indonesia

Michael Pitts / Jellyfish in open sea with fish protected in tentacles. Palau, Pacific.

Markus Varesvuo / White-tailed Eagle (Haliaeetus albicilla) mobbed by common gull (Larus canus) Flatanger, Norway, July

Anup Shah / Celebes / Black crested macaque (Macaca nigra) group gathering around a snake they have found on the beach, Tangkoko National Park, Sulawesi, Indonesia.

Anup Shah / Celebes / Black crested macaque (Macaca nigra) group gathering around a snake they have found on the beach, Tangkoko National Park, Sulawesi, Indonesia.

Steven Kazlowski / Walrus (Odobenus rosmarus) a cow fights off a bull's advances at the end of mating season, Bering Sea, off the coast of Alaska, USA

Alex Mustard / A wunderpus octopus (Wunderpus photogenicus) warning pose, which includes flared arms and strongly contrasting striped pattern, at the entrance to its burrow, Java Sea, Amed, Bali, Indonesia

Alex Mustard / A mimic octopus (Thaumoctopus mimicus) makes a 'poisonous sole' impression, Java Sea, Puri Jati, Bali, Indonesia. South East Asia, Java Sea

Alex Mustard / Mimic octopus (Thaumoctopus mimicus) hiding, half buried in the sand. Java Sea, Jati, Bali, Indonesia, South East Asia

Claudio Contreras / Foureye Butterflyfish (Chaetodon capistratus). Cancun National Park, Caribbean Sea, Mexico.

Alex Mustard / Flying gurnard (Dactylopterus volitans) swimming across the seabed displaying large open pectoral fins, Georgetown, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Tui De Roy / Ross Seal (Ommatophoca rossii) mother displaying with young pup on pack ice, Southern Ocean, eastern Antarctica

Nick Upton / A nectar-feeding species of Horse fly (Pangonius funebris), a carpenter bee mimic, using its long proboscis to forage on Milk thistle (Carduus marianus) near the coast with the sea in the background,...

Ingo Arndt / Southern Elephant Seal (Mirounga leonina) female displaying, Jason Harbor, South Georgia Island

Jeff Rotman / Symbiotic Two-band clownfish / Two bar anemonefish (Amphiprion bicinctus) hiding in the protection of the tentacles of a Magnificent Sea Anemone (Heteractis magnifica) Red Sea, Egypt

Jeff Rotman / Symbiotic Two-bar clownfish / Two-band anemonefish (Amphiprion bicinctus) hiding in the protection of a Sea anemone's tentacles. Red Sea, Egypt

Ernie Janes / Sea defences along the beach at Walcott, Norfolk, UK, Winter

Juergen Freund / Sea cucumber (Bohadschia marmorata) discharging sticky threads as a defence mechanism, Palawan, Philippines.

Juergen Freund / Soft coral mimicing nudibranch (Ceratosoma alleni) crawling over tunicates on coral reef, Anilao, Batangas, Philippines

Juergen Freund / Horsehoe crabs (Tachypleus gigas) in defensive posture on sandy seabed, Palawan, Philippines.

Juergen Freund / Two Horsehoe crabs (Tachypleus gigas) on sandy seabed, one in defensive posture, Palawan, Philippines.

Juergen Freund / Heart urchin (Echinocardium sp) of the family Loveniidae. These sea urchins are named for their shape. Lembeh Strait, North Sulawesi, Indonesia

Juergen Freund / Coconut octopus / veined octopus (Octopus marginatus) in a shelter made from a broken bottle and sealed with a large sea shell. Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Coconut octopus / veined octopus (Octopus marginatus) in a shelter made from a broken bottle and sealed with a large sea shell. Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Nudibranch (Phyllodesmium briareum) on the sea bed. This nudibranch mimics a soft coral. Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Carrier / Sea urchin crab (Dorippe frascone) carrying a fire urchin as a deterrent to predators. Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Saddleback anemonefish juvenile (Amphiprion polymnus) tending to freshly laid eggs. Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Four True clownfish / Clown anemonefish(Amphiprion percula) in their mostly-retracted anemone. North Raja Ampat, West Papua, Indonesia.

Juergen Freund / True clownfish / Clown anemonefish (Amphiprion percula) hiding among the tentacles of a sea anemone. Lembeh Strait, North Sulawesi, Indonesia

Juergen Freund / Sea cucumber (Bohadschia marmorata) discharges sticky threads as a defense mechanism when threatened, Palawan, Philippines, Indo-pacific.

Sergey Gorshkov / Steller's sea eagle (Haliaeetus pelagicus) mantling fish prey beside Lake Kuril, Kamchatka, Far East Russia, January

Sergey Gorshkov / Steller's sea eagle (Haliaeetus pelagicus) aggressive behaviour, Lake Kuril, Kamchatka, Far East Russia, January

Sergey Gorshkov / Steller's sea eagle (Haliaeetus pelagicus) mantling fish prey beside Lake Kuril, watched by other sea eagles, Kamchatka, Far East Russia, January

Sergey Gorshkov / Steller's sea eagle (Haliaeetus pelagicus) feeding on fish prey, mantling, Lake Kuril, Kamchatka, Far East Russia, January

Sergey Gorshkov / Steller's sea eagle (Haliaeetus pelagicus) defending fish prey, Lake Kuril, Kamchatka, Far East Russia, January

Philippe Clement / Sea-buckthorn (Hippophae rhamnoides) thorns and buds opening, Belgium

Tim Laman / Boxer crab (Lybia tesselata) holding small sea anemones in its claws (a mechanism for defense in this species). Bali, Indonesia

Jeff Rotman / Diver uses shark billy to fend off Caribbean Reef Shark (Carcharhinus perezi) Bahamas, Caribbean Sea Model released.

GEORGETTE DOUWMA / Clark's anemonefish (Amphiprion clarkii) with newly laid eggs, Papua New Guinea.

GEORGETTE DOUWMA / Mimic octopus (Thaumoctopus mimicus) hunting for prey over sandy seabed. One arm is investigating a burrow, while the skin between the other arms is streched to form a 'tent' to prevent any prey escap...

Jeff Rotman / Reef Octopus {Cyanea sp) inking snorkeler and wild Bottlenose Dolphin (Tursiops truncatus), Nuweiba, Egypt - Red Sea. Model released Model released.

Jeff Rotman / Orbicular burrfish / Short-spined porcupinefish (Cyclichthys orbicularis) puffed up with water, Lembeh Strait, Celebes Sea, Sulawesi, Indonesia.

Jeff Rotman / Orbicular burrfish / Short-spined porcupinefish (Cyclichthys orbicularis) puffed up with water, Lembeh Strait, Celebes Sea, Sulawesi, Indonesia.

Jeff Rotman / Mimic Octopus (Thaumoctopus mimicus) swimming, streamlined, mimicing a sea snake, Lembeh Strait, Celebes Sea, Sulawesi, Indonesia.

Jeff Rotman / Mimic Octopus (Thaumoctopus mimicus) swimming through water mimicing a flounder. Lembeh Strait, Celebes Sea, Sulawesi, Indonesia.

Fred Bavendam / Titan Triggerfish (Balistoides viridescens) with spines from a sea urchin it has eaten, Bali, Indonesia

Fred Bavendam / Leopard Sea Cucumber (Bohadschia argus) ejects mass of long white sticky tubules as a defense, Australia

Sue Daly / Beadlet anemone {Actinia equina} with tentacles partially extended, underwater, Gouliot Caves, Alderney, Channel Islands, UK

Juergen Freund / Sea cucumber {Holothuroidea} showing Cuvieren tube system excreted from anus in defense, Indo-pacific

Georgette Douwma / Sea urchin cardinalfish (Siphamia versicolor) sheltering amongst the spines of the venomous Fire urchin (Asthenosoma varium). Rinca, Indonesia.

Georgette Douwma / Sea urchin cardinalfish (Siphamia versicolor) sheltering amongst the spines of the venomous Fire urchin (Asthenosoma varium). Rinca, Indonesia.

Georgette Douwma / Sea urchin cardinalfish (Siphama versicolor) sheltering amongst the spines of urchin (Astropyga radiata). Rinca, Indonesia.

David Shale / Deep sea Glass squid {Cranchia sp} from Mid-Atlantic Ridge, squirting ink

Norbert Wu / Sea Cucumber exhibits escape response when threatened by arms of Sunflower Sea Stars (Pycnopodia helianthoides), Vancouver Island, British Columbia, Canada

Norbert Wu / Sea Cucumber exhibits escape response when threatened by arms of Sunflower Sea Stars (Pycnopodia helianthoides), Vancouver Island, British Columbia, Canada

Norbert Wu / Purple Sea Urchin (Strongylocentrotus purpuratus), Vancouver Island, British Columbia, Canada

Norbert Wu / Purple-ring Top Snail (Calliostoma annulatum) attacking Strawberry Anemone (Corynactis californica), California

Niall Benvie / Adult White tailed sea eagle (Haliaeetus albicilla) defending carcass from ravens, Estonia

Niall Benvie / Adult White tailed sea eagle (Haliaeetus albicilla) territorial desplay, defending its territory, Estonia

Michael Pitts / Caribbean reef squid {Sepioteuthis sepioidea} with tentacles splayed in defense posture, Belize, Caribbean Sea

GEORGETTE DOUWMA / Pharao cuttlefish (Sepia pharaonis) male guarding egg-laying female from approaching male, Andaman Sea, Thailand.

GEORGETTE DOUWMA / Pharao cuttlefish (Sepia pharaonis), very small male guarding large egg-laying female from approaching male, Andaman Sea, Thailand.

Florian Graner / Goosefish (Lophius sp) camouflaged against the sea-floor, Norway

Florian Graner / Goosefish (Lophius sp) camouflaged against the sea-floor, Norway

Luciano Candisani / Parrotfish (Sparisoma vetula) sleeps in mucus bubble for defense, Caribbean Sea, Bonaire Island, Netherlands Antilles

Jeff Rotman / Porcupinefish (Diodon hystrix) close-up of spines. Egypt, Red Sea.

Philippe Clement / North Sea, beach and sea dyke, Ostend, Belgium

Philippe Clement / North Sea, beach and sea dyke, Ostend, Belgium

Thomas Lazar / Bald Eagle (Haliaeetus leucocephalus) adult on sea ice with head raise giving territory call, standing with wings out encircling fish in talons, protecting food from other nearby adults, Kenai Peninsu...

Thomas Lazar / Bald Eagle (Haliaeetus leucocephalus) adult on sea ice standing with wings out encircling fish in talons, protecting food from other nearby adults, Kenai Peninsula, Alaska, USA

WILLIAM OSBORN / Sea holly close-up of flowers {Eryngium maritimus} Mid Glamorgan, Wales, UK

WILLIAM OSBORN / Sea holly on beach {Eryngium maritimus} Mid Glamorgan, Wales, UK

Juergen Freund / Diver with Crown of thorns starfish {Acanthaster planci} Indo-Pacific ocean

GEORGETTE DOUWMA / Table coral showing damage caused by Crown of Thorns starfish Red Sea Egypt

Piotr Naskrecki / Spinybacked Orb-weaver Spider (Gasteracantha cancriformis) their abdomen, or opisthosoma, is heavily sclerotized and armed with hard spines possibly to protect against birds and lizards, Solomon Islan...

GEORGETTE DOUWMA / Crown of thorns starfish {Acanthaster planci} Red Sea, Egypt

Doug Perrine / Leopard sea cucumber {Bohadschia argus} emitting sticky cuvierian tubules from anus as defense measure, Mabul Island, Borneo, Malaysia

Gary Smith / Wooden groynes - method of coastal defense against erosion - with choppy sea in sunshine, Norfolk, Uk

Gary Smith / Wooden groyne - method of coastal defense against sea erosion - at low tide, Norfolk, Uk.

Constantinos Petrinos / Nudibranch releases toxic slime under threat {Glossodoris hikuerensis} Sulawesi

Jeff Rotman / Masked Pufferfish {Arothron diadematus} inflated and hiding in coral, Red Sea, Egypt

Jeff Rotman / Striated sea cucumber {Pearsonalthuria graeffei}

Jeff Rotman / Masked Pufferfish {Arothron diadematus} inflated with water, Red Sea, Egypt

Jeff Rotman / Black blotched porcupinefish {Diodon liturosus} inflated, Red Sea, Egypt.

Jeff Rotman / Black blotched porcupinefish {Diodon liturosus} inflated, Red Sea, Egypt.