Kevin Schafer / Galapagos Sea Lion (Zalophus wollebaeki) pups playing, Espanola Island, Galapagos Islands, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) looking out to sea on sandy beach. Endangered. Espanola Island, Galapagos, Ecuador, June.

Juergen Freund / Shovelnose ray (Rhinobatidae) on the sandy bottom with a diver. Tigabu Island, Malaysia, June 2009. Model released.

Juergen Freund / Aerial view of private tropical island surrounded by a white sandy beach and coral reefs, note helipad on end of pier, Palawan, Philippines, May 2009.

Billy Black / Distant figures with kayak on Sandy Island, near Carriacou Island, the Grenadines, Caribbean, January 2010.

Sue Flood / Woman tourist relaxing in hammock on tropical beach, Deadman's Bay, Peter Island, British Virgin Islands, April 2008, Model released

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) on sandy beach. Endangered. Seymour Island, Galapagos, Ecuador, June.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) on sandy beach. Endangered. Seymour Island, Galapagos, Ecuador, June.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) leaning against log on sandy beach. Endangered. Seymour Island, Galapagos, Ecuador, June.

Tui De Roy / Galapagos sea lions (Zalophus wollebaeki) reating on sandy beach. Endangered. Espanola Island, Galapagos, Ecuador, June.

Tui De Roy / Galapagos sea lions (Zalophus wollebaeki) resting on sandy beach. Endangered. Espanola Island, Galapagos, Ecuador, June.

Billy Black / Two common bottlenosed dolphins (Tursiops truncatus) off sandy beach with a Surf Hunter 29 Inboard. Collier Bay, Marco Island, Florida, USA. Property released, February 2007.

Konrad Wothe / Cardwell Beach with mangroves near Hinchinbrook Island, Queensland, Australia, October 2010

Juergen Freund / Shovelnose ray (Rhinobatidae) on the sandy bottom. Tigabu Island, Malaysia, June 2009.

Juergen Freund / Aerial of white sandy beach island resort, Palawan, Philippines, April 2010.

Juergen Freund / Aerial view of a private tropical island surrounded by a white sandy beach and coral reefs. note helipad at end of pier at top left of the island, Palawan, Philippines, April 2010.

Juergen Freund / Split level of Horned sea stars / chocolate chip starfish (Protoreaster nodosus) in the shallow sandy area with island in the background, Komodo NP, Indonesia.

Juergen Freund / Aerial view of coastal island community with outrigger boats on sandy beach, Palawan, Philippines, May 2009.

Juergen Freund / Aerial view of private tropical island surrounded by a white sandy beach and coral reefs, note helipad on end of pier, Palawan, Philippines, May 2009.

Juergen Freund / Aerial view of coastal island community with outrigger boats and white sandy beaches, Palawan, Philippines, May 2009.

Juergen Freund / Horned sea stars / Chocolate chip stafish (Protoreaster nodosus) on sandy seabed in shallow water, split level with an island in the background, Komodo NP, Indonesia, Indo-pacific, August 2009.

Juergen Freund / Young woman in "bridge" yoga pose on a sandy beach. Daram Island, Raja Ampat, West Papua, Indonesia, January 2010, model released.

Juergen Freund / Young woman in "bridge" yoga pose on a sandy beach. Daram Island, Raja Ampat, West Papua, Indonesia, January 2010.

Juergen Freund / Young woman in a yoga pose on a sandy beach. Daram Island, Raja Ampat, West Papua, Indonesia, January 2010.

Juergen Freund / A man and woman walking along the tideline of a white sandy beach. Daram Island, Misool, Raja Ampat, West Papua, Indonesia, January 2010.

Brent Stephenson / Weka (Gallirallus australis) walking along a sandy beach. Ulva Island, Stewart Island, New Zealand.

Billy Black / Rain shower across Sandy Island, the Grenadines, Caribbean, January 2010.

Billy Black / Figure beneath rainbow on Sandy Island, near Carriacou Island, the Grenadines, Caribbean, January 2010.

Steven David Miller / View of Great Sandy Strait, Fraser Island, Queensland, Australia September 2009

Juergen Freund / Split level of coral reef and Sandy Beach Resort, Ha'apai Islands, Tonga, Melanesia, Pacific

Juergen Freund / Joanna Browne collecting an 'upside down jellyfish' {Cassiopeia sp} from the sandy bottom of Lizard Island lagoon, for Coral Reef census, Lizard Island, Queensland, Australia, April 2008

Juergen Freund / Split level of granite rocks in sandy lagoon, Lizard Island, Queensland, Australia, April 2008.

Juergen Freund / Split level of granite rocks in sandy lagoon, Lizard Island, Queensland, Australia, April 2008.

Andrew Walmsley / South Island pied oystercatcher (Haematopus finschi) feeding on a sandy beach, Christchurch, New Zealand, February

Andrew Walmsley / South Island pied oystercatcher (Haematopus finschi) walking on sandy beach, Christchurch, New Zealand, May

Andrew Walmsley / South Island pied oystercatchers (Haematopus finschi) at roost on sandy beach, Christchurch, New Zealand, May

Tim Laman / Fiddler crabs {Uca sp} living in a sandy tidal flat among the spike-like finger roots of {Sonneratia alba} mangrove trees. Kostrae Island, Federated States of Micronesia.

Tim Laman / Fiddler crabs {Uca sp} living in a sandy tidal flat among the spike-like finger roots of Mangrove apple trees {Sonneratia alba}. Kostrae Island, Federated States of Micronesia.

Tim Laman / Fiddler crab {Uca sp} living in a sandy tidal flat among the spike-like finger roots of Mangrove apple trees {Sonneratia alba} Kostrae Island, Federated States of Micronesia.

Tim Laman / Fiddler crabs {Uca sp} living in a sandy tidal flat among the spike-like finger roots of {Sonneratia alba} mangrove trees. Kostrae Island, Federated States of Micronesia.

Tim Laman / Fiddler crab {Uca sp} living in a sandy tidal flat among the spike-like finger roots of Mangrove apple trees {Sonneratia alba}. Kostrae Island, Federated States of Micronesia.

Tim Laman / Fiddler crabs {Uca sp} living in a sandy tidal flat among the spike-like finger roots of Mangrove apple trees {Sonneratia alba}. Kostrae Island, Federated States of Micronesia.

Roger Powell / Winter plumaged Grey plover (Pluvialis squatarola) on sandy estuary feeding grounds. Holy Island, Northumberland, UK

Colin Monteath / Royal Penguin (Eudyptes schlegeli) group walking on beach, Sandy Bay, Macquarie Island, Subantarctic, Australia

Colin Monteath / Southern Elephant Seal (Mirounga leonina) juveniles sparring, Sandy Bay, Macquarie Island, Subantarctic, Australia

Yva Momatiuk & John Eastcott / Southern Elephant Seal (Mirounga leonina) bull resting on sandy beach, Right Whale Bay, South Georgia Island

Theo Allofs / Large driftwood root on sandy beach south of Cape Foulwind, New Zealand

Inaki Relanzon / Aerial view of the island of Nosy Tanikely with sandy beach on one side and rocky coast on the other, near Nosy Be, North Madagascar.

Inaki Relanzon / Aerial view of the island of Nosy Tanikely with sandy beach on one side and rocky coast on the other, near Nosy Be, North Madagascar.

Paul Hobson / Two Australian sealions (Neophoca cinerea) touching noses on sandy beach, Kangaroo Island, South Australia

Paul Hobson / Australian sealion (Neophoca cinerea) on sandy beach, Kangaroo Island, South Australia

Paul Hobson / Australian sealion (Neophoca cinerea) female on sandy beach, Kangaroo Island, South Australia

Mike Parry / Dugong (Dugong dugon) returning to surface after resting on the sandy sea floor, Lamen Bay, Epi Island, Vanuatu

Konrad Wothe / Royal Penguin (Eudyptes schlegeli) group and Southern Elephant Seals (Mirounga leonina) on beach, Macquarie Island, Australia

Yva Momatiuk & John Eastcott / Gentle sea waves rolling on sandy St. Kilda Beach in soft morning light, winter, Dunedin, Otago, South Island, New Zealand

Jeff Rotman / Allmouth / Goosefish (Lophius piscatorius) camouflaged on sandy bottom. Glenan Island, France, Atlantic Ocean.

Tim Fitzharris / Dune vegetation and shorebird tracks in sand, Santa Rosa Island, Gulf Islands National Seashore, Florida

Tom Vezo / American oystercatcher {Haematopus palliatus} walking on sandy beach, Long Island, NY, USA

Pete Oxford / Royal Penguins {Eudyptes schlegeli} arguing, Sandy Bay, Macquarie Island, Tasmania, Australia

Mike Parry / Dugong (Dugong dugon) returning to surface after sleeping/resting on the sandy sea floor, Lamen Bay, Epi Island, Vanuatu

Konrad Wothe / Royal Penguin (Eudyptes schlegeli) coming ashore, Macquarie Island, Australia

Konrad Wothe / Royal Penguin (Eudyptes schlegeli) running out of surf, Macquarie Island, Australia

Konrad Wothe / Royal Penguin (Eudyptes schlegeli) pair on nest, Macquarie Island, Australia

Tui De Roy / Yellow-eyed Penguin (Megadyptes antipodes) commuting to nest hidden inland in dense vegetation, Sandy Bay, Enderby Island, Auckland Islands, New Zealand

Tui De Roy / Yellow-eyed Penguin (Megadyptes antipodes) pair commuting to nest hidden inland in dense vegetation, Sandy Bay, Enderby Island, Auckland Islands, New Zealand

Tui De Roy / Yellow-eyed Penguin (Megadyptes antipodes) commuting to nest hidden inland in dense vegetation, Sandy Bay, Enderby Island, Auckland Islands, New Zealand

Tui De Roy / Yellow-eyed Penguin (Megadyptes antipodes) commuting to nest hidden inland in dense vegetation, Sandy Bay, Enderby Island, Auckland Islands, New Zealand

Tui De Roy / Yellow-eyed Penguin (Megadyptes antipodes) group of three commuting to nest hidden in dense inland vegetation, Sandy Bay, Enderby Islands, Auckland Group, New Zealand

Tui De Roy / Yellow-eyed Penguin (Megadyptes antipodes) group of five commuting to nest hidden in dense inland vegetation, Sandy Bay, Enderby Islands, Auckland Group, New Zealand

Tui De Roy / Royal Penguin (Eudyptes schlegeli) pair on landing beach, Sandy Bay, Macquarie Island, Australia

Norbert Wu / Pine Cone Algae (Rhipocephalus sp) tiny clumps of algae growing in well-lit sandy ocean floor, Roatan Island, Honduras

Pete Oxford / Tourist photographing Royal penguin on beach on Macquarie Island, Tasmania, Australia

Pete Oxford / Royal penguins (Eudyptes schlegeli). Sandy Bay, Macquarie Island, Tasmania, Australia

Pete Oxford / Royal penguins (Eudyptes schlegeli). Sandy Bay, Macquarie Island Tasmania, Australia

Pete Oxford / Royal penguins (Eudyptes schlegeli). Sandy Bay, Macquarie Island, Tasmania, Australia

Onne van der Wal / Three children playing on a long sandy beach, South Island, New Zealand.

Onne van der Wal / Child running along a long sandy beach, South Island, New Zealand.

Onne van der Wal / People standing on the hilltop overlooking a sandy beach, South Island, New Zealand.

Onne van der Wal / Sandy beach, South Island, New Zealand.

Onne van der Wal / Sandy beach, South Island, New Zealand.

Onne van der Wal / A small island with sandy beach in the Northern Vava'u island group, Tonga, South Pacific.

Onne van der Wal / A small island with sandy beach in the Northern Vava'u island group, Tonga, South Pacific.

Roberto Rinaldi / Yacht at Sandy Cay, Jost Van Dyke Island, British Virgin Islands (BVI)

Roberto Rinaldi / Sandy beach on White Bay, Jost Van Dyke Island(JV Dyke), also known as Barefoot Island, British Virgin Islands (BVI)

Roberto Rinaldi / Sandy Cay beach, Jost Van Dyke Island, British Virgin Islands (BVI)

Roberto Rinaldi / Sandy Cay on Jost Van Dyke Island (JV Dyke), British Virgin Islands (BVI)

Roberto Rinaldi / Deserted sandy beach on Ile des Pins (Isle of Pines / Kanak Island), Grande Terre, New Caledonia, Melanesia.

Roberto Rinaldi / View from cliff-top of sandy bay on Lord Howe Island, New South Wales, Australia.

Angelo Giampiccolo / Fishing boats on a sandy beach. Balicasag Island, Bohol, Philippines.

Angelo Giampiccolo / Horseshoe crab (Limulus sp) moving on sandy beach, Long Island, New York, USA.

Colin Monteath / King Penguin (Aptenodytes patagonicus) investigating photographer, Sandy Bay, Macquarie Island, Subantarctic, Australia

Colin Monteath / Seaweed in Sandy Bay, Macquarie Island, Subantarctic, Australia

Roberto Rinaldi / Boat approaching Sandy Cay on Jost Van Dyke Island (JV Dyke), British Virgin Islands (BVI).

Roberto Rinaldi / Woman sunbathing on the sandy shore, Lankayan Island, Borneo. Model released.

Mitsuaki Iwago / Australian Sea Lion (Neophoca cinerea) pair sunning on a sandy beach at sunset, Kangaroo Island, Australia

Yva Momatiuk & John Eastcott / Gentle surf rolling on sandy beach at sunrise in winter, Westland, West Coast, South Island, New Zealand