Alex Mustard / Southern stingray (Hypanus americanus) swimming over ripples on sandbar, Grand Cayman, Cayman Islands.

Alex Mustard / Southern stingray (Hypanus americanus) swimming over sand ripples on sandbar, Stingray City, Grand Cayman. British West Indies.

Alex Mustard / A school of Southern stingrays (Hypanus americanus) on a sand bar, Grand Cayman, Cayman Islands. British West Indies. Caribbean Sea.

Alex Mustard / Southern stingray (Hypanus americanus) swimming over sand ripples on sandbar, Grand Cayman, Cayman Islands.

Doug Perrine / Sandbar shark {Carcharhinus plumbeus}, Pacific Ocean.

Doug Perrine / Sandbar shark {Carcharhinus plumbeus}, Pacific Ocean.

Flip Nicklin / Sandbar Shark (Carcharhinus plumbeus) underwater portrait, bottom-dwelling coastal species, worldwide distribution

Doug Perrine / Sandbar shark abstract {Carcharhinus plumbeus} Hawaii (Non-ex).

Alex Mustard / Southern stingray (Hypanus americanus) female swimming over ripples on a sand bank, photographed with a circular fisheye lens, The Sandbar, Grand Cayman, Cayman Islands, British West Indies, Caribbean...

Alex Mustard / Sand ripples, The Sandbar, North Sound, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Underwater shallow sand bar with ripples, North Sound, Grand Cayman, Cayman Islands, British West Indies. Caribbean Sea.

Luciano Candisani / Jacare Caiman (Caiman yacare) pair sunning on sandbar, Pantanal, Brazil

Alex Mustard / Southern stingray (Hypanus americanus) swimming over a sandbar, Grand Cayman, Cayman Islands. British West Indies. Caribbean Sea.

Alex Mustard / A southern stingray (Hypanus americanus) over a sandbar. Grand Cayman, Cayman Islands. British West Indies. Caribbean Sea.

Alex Mustard / Southern stingray (Hypanus americanus) swimming over a sandbar, Grand Cayman, Cayman Islands. British West Indies, Caribbean Sea.

Luciano Candisani / Aerial view of the Rio Negro in dry season showing meandering habit with point bars, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) sunning on sandbar, Pantanal, Brazil

Peter Lewis / Sandbar (Tombolo) connecting St Ninians Isle to the mainland Shetland Isles, the sand is above sea level except at extremely high tides, and is accessible to walkers, Shetland Isles, Scotland, UK

Doug Perrine / Dead Sandbar shark hanging under fishing boat {Carcharhinus plumbeus} killed by longline fishing, Philippines

Flip Nicklin / Sandbar Shark (Carcharhinus plumbeus) underwater portrait, bottom-dwelling coastal species, worldwide distribution

Flip Nicklin / Sandbar Shark (Carcharhinus plumbeus) underwater portrait, bottom-dwelling coastal species, worldwide distribution

Flip Nicklin / Sandbar Shark (Carcharhinus plumbeus) underwater portrait, bottom-dwelling coastal species, worldwide distribution

Bob Barbour / Kieran Horn, off-the-wall, Oahu, Hawaii

Bob Barbour / Kieran Horn, Pupukea Sandbar, Oahu, Hawaii

Bob Barbour / Kieran Horn, Pupukea Sandbar, Oahu, Hawaii

Jeff Rotman / Sandbar shark {Carcharhinus plumbeus} caught on long-line fishing, Mediterranean, Israel

Jeff Rotman / Sandbar shark caught on long line. Mediterranean. Israel Model released.

Jeff Rotman / Diver next to Sandbar shark caught on fishline (Carcharhinus plumbeus) Mediterranean long line fishing Model released.

Martin Willis / Beach Stone-curlew (Esacus magnirostris) pair on sandbar, Toolakea Beach, Queensland, Australia

Juergen Freund / Spotted scorpionfish {Scorpaena plumieri} camouflaged on sandbar, Caribbean

Flip Nicklin / Sandbar Shark (Carcharhinus plumbeus) underwater portrait, bottom-dwelling coastal species, worldwide distribution