Erlend Haarberg / Stoat (Mustela erminea) in white winter coat, trying to steal fish (trout) hanging on transparent fishing line. Vauldalen, Sor-Trondelag, Norway, April

Ann & Steve Toon / Osprey (Pandion haliaetus) catching trout, Rothiemurchus estate, Cairngorms, Scotland, UK, July

Linda Pitkin / 2020VISION / Arctic charr (Salvelinus alpinus) males showing breeding colours, in a river where they have come to spawn, Ennerdale Valley, Lake District NP, Cumbria, England, UK, November 2011. 2020VISION Exhibiti...

Linda Pitkin / 2020VISION / Arctic charr (Salvelinus alpinus) female with males showing breeding colours, in spawning river, Ennerdale Valley, Lake District NP, Cumbria, England, UK, November 2011

Linda Pitkin / 2020VISION / Arctic charr (Salvelinus alpinus) males showing breeding colours, in spawning river, Ennerdale Valley, Lake District NP, Cumbria, England, UK, November 2011

Laurent Geslin / Arctic charr (Salvelinus alpinus) eggs, collected from Lake of Geneva, France, December 2007.

Charlie Summers / Brook trout (Salvelinus fontinalis) in breeding colouration, migrating upstream to spawn, Colorado, USA, September.

Remi Masson / Brook trout (Salvelinus fontinalis) in a mountain lake. Savoie, Alps, France

Charlie Summers / Brook trout (Salvelinus fontinalis) depositing roe into the redd she built while a male waits nearby to come and fertilize the eggs. Rocky Mountain National Park, Colorado, USA, October.

Nick Hawkins / Brook trout (Salvelinus fontinalis) close up of skin / scales, Miramichi River, New Brunswick, Canada, June.

Jussi Murtosaari / Arctic charr (Salvelinus alpinus), Finland, July.

Charlie Summers / Brook trout (Salvelinus fontinalis) female fanning her tail as she digs a redd or nest in her spawning stream. Image taken in Rocky Mountain National Park of Colorado.