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 / 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.

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

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...

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

Remi Masson / Group of Barbels (Barbus barbus) spawning, River Rhone, Rhone-Alpes, France, April.

Remi Masson / Group of Nase (Chondrostoma nasus) and Barbels (Barbus barbus) spawning, River Rhone, Rhone-Alpes, France, April.

Remi Masson / Shoal of Nase (Chondrostoma nasus) spawning, River Ain, Rhone-Alpes, France, April.

Konrad Wothe / Chub (Squalius cephalus) trying to catch a Banded demoiselle (Calopteryx splendens), Bavaria, Germany, June.