Remi Masson / Pike (Esox lucius) hunting in a shoal of Perch (Perca fluviatilis), Lake Neuchatel, Switzerland. June.

Remi Masson / Large Pike (Esox lucius) more than a meter long, resting on a lake bed, Lake Neuchatel, Switzerland. June.

Remi Masson / European beaver (Castor fiber) eating branches in the water before approaching the camera, River Rhone, Rhone-Alpes, France, June.

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

Remi Masson / Water lilies (Nymphaea alba) lit by the sun's rays, seen under water. Alps, Ain, France. June. Highly commended in the the Underwater World category, GDT European Wildlife Photographer of the Year 201...

Remi Masson / Common toads (Bufo bufo) mating surrounded by strings of toadspawn. Ain, Alps, France. First prize in the category "The Underwater World, GDT European Wildlife Photographer of the Year 2014 competiti...

Remi Masson / Group of Black bullhead (Ameiurus melas) shoaling to protect themselves against predators, River Rhone, Rhone-Alpes, France, July.

Remi Masson / Tracking shot of a Eurasian beaver (Castor fiber) swimming underwater, turns to look at camera, River Rhone, Rhone-Alpes, France, June.

Remi Masson / Eurasian beaver (Castor fiber) carrying branches back to lodge, dropping them when alarmed. River Rhone, Rhone-Alpes, France, June.

Remi Masson / Pair of Pumpkinseeds (Lepomis gibbosus) mating, male chasing other individuals away, River Rhone, Rhone-Alpes, France, June.

Remi Masson / Male Common toads (Bufo bufo) fighting underwater during mating season, with a pair mating Ain, Rhone-Alps, France, March.

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