Alex Mustard / Caribbean reef squid (Sepioteuthis sepioidea) North Wall, Grand Cayman, Cayman Islands, West Indies, Caribbean Sea

Alex Mustard / A Caribbean reef squid (Sepioteuthis sepioidea) perches on the hand of a diver. North Wall, Grand Cayman, Cayman Islands, West Indies, Caribbean Sea, April 2008, no release available.

Juan Carlos Munoz / Aerial view of the 'Long Wall', sand dunes along the Atlantic coast of the Namib desert, Swakopmund, Namibia, August 2008

Terry Whittaker / 2020VISION / Flock of Dark-bellied brent geese (Branta bernicla) flying over sea wall, South Swale, Kent, England, UK

Alex Mustard / Pederson cleaner shrimp (Periclimenes pedersoni) cleaning the eye of a Nassau grouper (Epinephelus striatus), Bloody Bay Wall, Little Cayman, Cayman Islands. British West Indies, Caribbean Sea.

Alex Mustard / Caribbean spiny lobster (Panulirus argus) scampers across a coral reef amongst sponges, Bloody Bay Wall, Little Cayman, Cayman Islands. British West Indies, Caribbean Sea.

Alex Mustard / Lionfish (Pterois volitans) sitting on the rim of large sponge on Bloody Bay Wall, Little Cayman, Cayman Islands, Caribbean Sea.

Nick Garbutt / Painted houses along the sea front, Tobermory, Isle of Mull, Inner Hebrides, Scotland, UK, June 2010

Jeff Rotman / Child snorkeling and exploring on coral reef wall. Red Sea, Egypt. Model released Model released.

Ernie Janes / Turnstones (Arenaria interpres) perched on sea wall with pier in background, Norfolk, UK, March

Philip Stephen / Fishing vessel "Ocean Pioneer" nearing Fraserburgh Harbour, with waves crashing against the harbour wall. Scotland, February 2011.

David Tipling / Three people watching common starlings (Sturnus vulgaris) arriving to roost at Palace Pier Brighton. UK, February

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

David Woodfall / A sea wall being built to protect fishing village from floods, in response to rising sea levels due to climate change, Sundarbans, Bangladesh, June 2008

David Woodfall / A sea wall being built to protect fishing village from floods, in response to rising sea levels due to climate change, Sundarbans, Bangladesh, June 2008

Juan Carlos Munoz / The "Long Wall", aerial view of sand dunes bordering the atlantic coast, near Swakopmund, Namib desert, Namibia, August 2008

Gavin Hellier / Fishing boats moored by the harbour wall in Rozel bay, Jersey, Channel Islands, 2009

Georgette Douwma / Red Soldierfish (Myripristis murdjan) sheltering on coral wall. Egypt, Red Sea.

Georgette Douwma / Red Soldierfish (Myripristis murdjan) sheltering on coral wall. Egypt, Red Sea.

Alex Mustard / Diver photographing a large formation of yellow tube sponges (Aplysina fistularis) growing on a coral reef, North Wall, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea. Model released...

Alex Mustard / 2020VISION / Short plumose anemones (Metridium senile) on wall of a sealoch, this species favours areas of strong current, both white and orange forms, Loch Long, Argyll and Bute, Scotland, UK, June

Nick Upton / Flock of Barnacle geese (Branta leucopsis) resting and preening on water margin of flooded pastureland near the Severn estuary sea wall, Gloucestershire, UK, March

Terry Whittaker / 2020VISION / View of a breached sea wall, with established saltmarsh on right and regenerating habitat on left, such breaches are purposefully made and are part of the regeneration of saltmarsh landscape, providin...

Terry Whittaker / 2020VISION / Tide rushing through a purposefully made breach in a sea wall, such breaches are part of the regeneration of saltmarsh landscape, providing both a rich wildlife habitat and greater flood protection fr...

Terry Whittaker / 2020VISION / Landscape showing eroding saltmarsh against a sea wall, the majority of saltmarsh habitat that is lost in the UK is caused by similar 'hard' coastal defences preventing the landward migration of saltm...

Terry Whittaker / 2020VISION / Landscape showing eroding saltmarsh against a sea wall, the majority of saltmarsh habitat that is lost in the UK is caused by similar 'hard' coastal defences preventing the landward migration of saltm...

Alex Mustard / Goliath grouper (Epinephelus itajara) on a rich coral reef with a diver swimming alongside, Bloody Bay Wall, Little Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Diver tickling Nassau grouper (Epinephelus striatus) Bloody Bay Wall, Little Cayman, Cayman Islands. British West Indies, Caribbean Sea. Model released.

Alex Mustard / Brown tube sponges (Agelas conifera) formation on reef wall with diver above, image taken with a circular fisheye, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Brown tube sponges (Agelas conifera) formation on reef wall, with diver in distance, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Giant barrel sponges (Xestospongia muta) young group on the wall of a coral reef, with diver above in distance, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Brown tube sponges (Agelas conifera) formation on a reef wall, with sun shining through the water and diver above, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / A pair of sponges (Porifera) at the base of a pinnacle off the main reef wall with diver in background, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Red clingfish (Arcos rubiginosus) living on a deepwater sea fan (Iciligorgia nodulifera) on the reef wall, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Red rope sponge (Amphimedon compressa) on coral reef wall with diver in background, High Rock Drop Off, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Terry Whittaker / 2020VISION / Regenerating saltmarsh and sea wall breaches, Wallasea Wild Coast Project, RSPB Greater Thames Futurescapes Project, Wallasea Island, Essex, England, UK, October 2011

Ernie Janes / Flock of Turnstones (Arenaria interpres) drinking at freshewater pool behind the sea wall, Norfolk, UK, February

Ernie Janes / Broken sea wall caused by wave erosion and storm damage, Happisburgh, Norfolk, UK, winter

Juergen Freund / Fan corals (Gorgonacea) on the coral wall. Misool, Raja Ampat, West Papua, Indonesia, January.

Juergen Freund / Fan corals (Gorgonacea) on the coral wall. Misool, Raja Ampat, West Papua, Indonesia.

Juergen Freund / Fan corals (Gorgonacea) on the coral wall. Misool, Raja Ampat, West Papua, Indonesia.

Juergen Freund / Fan corals (Gorgonacea) on the coral wall with diver in the background. Misool, Raja Ampat, West Papua, Indonesia, January 2010

Matthias Breiter / Giant Green Sea Anemone (Anthopleura xanthogrammica) group and Ochre Sea Stars (Pisaster ochraceus) on rock wall on St. Lazaria Island, Alaska

Toby Roxburgh / Rock mounds laid out as coast defence along the shoreline just north of the old Severn Crossing, River Severn, England, 2010.

Nick Upton / Yellow-legged gull (Larus michahellis) standing on city wall high above the sea. Bonifacio, Corsica, May.

Nick Upton / Yellow-legged gull (Larus michahellis) standing on city wall high above the sea, with limestone cliffs in the background. Bonifacio, Corsica, May.

Nick Upton / Yellow-legged gull (Larus michahellis) standing on city wall high above the sea, with limestone cliffs in the background. Bonifacio, Corsica, May.

Alex Mustard / A pair of shy young California sealions (Zalophus californianus) peer out from against a colourful, coral encrusted wall, inside an underwater cave. Los Isotes, La Paz, Mexico. Sea of Cortez, East Pac...

Pete Oxford / Aerial view of the sea wall protecting Georgetown, a city built below sea level, Guyana, December 2009

Aflo / ic-00703 Domestic tabby cat sitting on sea wall {Felis catus}

Aflo / ic-00701 Domestic cat resting on sea wall {Felis catus}

Aflo / ic-00605 Domestic cat sitting on sea wall {Felis catus}

Aflo / ic-00604 Domestic cat sitting on sea wall rear view {Felis catus}

David Woodfall / Grazing Freisian cattle (Bos taurus) on sea wall Lydney marsh, Severn Estuary, Gloucestershire, England

David Woodfall / Men buiding sea wall to combat rising sea levels, climate change, Ganges delta, Bangladesh, July 2008

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

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

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

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

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

Sue Flood / Shovels hung up against wall in Captain Scott's hut, Cape Evans, Ross Island, Ross Sea, Antarctica, December 2008

Juan Carlos Munoz / The "Long Wall", aerial view of sand dunes bordering the atlantic coast, near Swakopmund, Namib desert, Namibia, August 2008

Alan Williams / Carrion crow (Corvus corone) scavenging food from a dead crab on sea wall, Liverpool Bay, UK, February

Alan Williams / Brent goose (Branta bernicla) flock flying in over sea wall to feed on farmland, Whitstable, Kent, UK, January

Alan Williams / Brent goose (Branta bernicla) flock flying in over sea wall to feed on farmland, Whitstable, Kent, UK, January

Philippe Clement / Harbour wall and lighthouse at Saint-Vaast-la-Hogue, Normandy, France, December 2008

Philippe Clement / Harbour wall and lighthouse at Saint-Vaast-la-Hogue, Normandy, France, December 2008

Philippe Clement / Waves crashing into jetty and over harbour wall during storm at Saint-Valéry-en-Caux, Normandy, France, December 2008

Philippe Clement / Waves crashing into jetty and over harbour wall during storm at Saint-Valéry-en-Caux, Normandy, France, December 2008

Merryn Thomas / Berber leaning over sea wall in Essaouira, Morocco, November 2008.

Fred Bavendam / Slate Pencil Urchin (Heterocentrotus mammillatus) pair attached to rock wall, Kona, Hawaii

Michele Westmorland / Reef wall covered with corals, sponges and starfish. Bev's Reef, Tufi, Papua New Guinea

Yva Momatiuk & John Eastcott / Crumbling blocks and wall of blue glacier marked by morraine debris descending toward sea, Neumayer Glacier, South Georgia Island

Yva Momatiuk & John Eastcott / Wall of blue glacier descending toward sea with cumulus clouds and mountains of Allardyce Range behind, Neumayer Glacier, South Georgia Island

Gary K. Smith / Cley Nature Reserve, showing freshwater marsh, reedbeds, birdwatching hides, sea wall and sea in distance, North Norfolk, UK

Graham Eaton / Black-headed Gull (Chroicocephalus ridibundus) on sea wall, Cemlyn, UK, June

Georgette Douwma / Necklace sea star (Fromia monilis) on reef wall with sponges, Rinca, Indonesia

Gary K. Smith / Reedbed (Phragmites australis), coastal freshmarsh, dyke and sea wall, Salthouse, Norfolk, England, UK

Gary K. Smith / Reedbed (Phragmites australis), coastal freshmarsh, dyke and sea wall, Salthouse, Norfolk, England, UK

Gary K. Smith / Coastal car park flooded by water from freshwater marsh, sea wall in background, North Norfolk, UK

Gary K. Smith / Coastal car park flooded by water from freshwater marsh, sea wall in background, North Norfolk, UK

Kirkendall-Spring / Rocks in the surf at Hole-in-the-Wall on the Pacific Coast, Olympic NP, Washington, USA

GEORGETTE DOUWMA / Large pincushion starfish (Culcita novaguinea) on reef wall. Andaman Sea, Thailand.

Kirkendall-Spring / Sunset at the Hole-in-the-Wall, pacific coast, Olympic National Park, Washington, USA

Pete Cairns / White tailed Sea Eagle (Haliaeetus albicilla) looking out over sheep pasture, Mull Argyll, Scotland, UK captive

GEORGETTE DOUWMA / Ochre sea stars {Pisaster ochraeceus} and Giant green anemones {Anthopleura xanthogrammica} exposed on rock wall during low tide, Olympic National Park, Washington, USA.

GEORGETTE DOUWMA / Ochre sea star {Pisaster ochraeceus} exposed on rock wall at low tide, Olympic National Park, Washington, USA.

GEORGETTE DOUWMA / Ochre sea stars {Pisaster ochraeceus} exposed on rock wall at low tide, Olympic National Park, Washington, USA.

Barry Bland / Waves crashing against sea wall near beach huts, Southwold, Suffolk, UK.

Norbert Wu / French Angelfish (Pomacanthus paru) along coral wall, Saba, Caribbean

Norbert Wu / Basslet (Pseudanthias sp) school crowds coral wall with colorful Soft Corals (Dendronephthya sp), Red Sea

Fred Bavendam / Sea Star (Leiaster sp) crawling among Stony Coral (Tubastraea sp) on a reef wall, Manado, North Sulawesi, Indonesia

Fred Bavendam / Spine-cheek Anemonefish (Premnas biaculeatus) living on a Bulb Tentacle Sea Anemone (Entacmaea quadricolor) on a reef wall, Manado, Indonesia

Fred Bavendam / Giant Green Sea Anemone (Anthopleura xanthogrammica) trio in tide pool, browning wall, British Columbia, Canada