Alex Mustard / Yellowtail tang (Zebrasoma xanthurum) male and female turn belly to belly during spawning to ensure fertilization. Temple, Ras Umm Sid, Sharm El Sheikh, Sinai, Egypt. Red Sea. This action is very fast...

Alex Mustard / Southern stingray (Dasyatis americana) two swimming over sand bar, under stormy sky. Grand Cayman, Cayman Islands. British West Indies.

Alex Mustard / Dugong (Dugong dugon) male and juvenile Golden trevally (Gnathanodon speciosus) swimming over Seagrass (Halophila stipulacea) meadow. Marsa Nabaa, Marsa Alam, Egypt.

Alex Mustard / Green turtle (Chelonia mydas) resting on sea floor and two juvenile Golden trevally (Gnathanodon speciosus). Marsa El Shouna, Marsa Alam, Egypt.

Alex Mustard / Oceanic whitetip shark (Carcharhinus longimanus) swimming close to surface. Brothers Islands, Egypt.

Shane Gross / Flying fish (Exocoetidae) in Sargasso Sea, Atlantic Ocean.

Shane Gross / Caribbean reef shark (Carcharhinus perezi), two from below, one close up. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Alex Mustard / Whale shark (Rhincodon typus) close to the camera with a golden trevally fish (Gnathanodon speciosus) and outline of another whale shark behind , in the plankton-rich green waters of La Paz bay, Baja...

Franco Banfi / School of Munk's devil ray, pygmy devil ray, (Mobula munkiana), feeding on plankton at night, photographed on a long exposure, Espiritu Santo Island, Sea of Cortez, Baja California, Mexico, East Pacif...

Shane Gross / Almaco jack (Seriola rivoliana) uses a discarded fishing net, drifting in the open ocean as shelter. The Bahamas.

Nick Hawkins / Blue shark (Prionace glauca) with a pair of pilot fish (Naucrates ductor) off Halifax, Nova Scotia, Canada. July.

David Pattyn / Great crested grebe (Podiceps cristatus) adult with freshly caught fish. Tench (Tinca tinca) to feed to its young chick, Valkenhorst Nature Reserve, Valkenswaard, The Netherlands, June