Alex Mustard / Southern stingray (Dasyatis americana) swimming over sand in shallow water, split level photo with blue sky and clouds. The Sandbar, Grand Cayman, Cayman Islands. British West Indies. Caribbean Sea.

Juergen Freund / Banded archerfish (Toxotes jaculatrix) spitting, Oolioo Sandbar, Territory Wildlife Park, Berry Springs, Northern Territory, Australia.

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).

John Chan / Breeding colony of Elegant terns (Sterna elegans) gathered on a sandbar, Bolsa Chica Ecological Reserve, California, USA, March.

John Chan / Breeding colony of Elegant terns (Sterna elegans) gathered on a sandbar, Bolsa Chica Ecological Reserve, California, USA, March.