Ingo Arndt / Mass of Sea trout (Salmo trutta trutta) eggs, with embryos visible, Europe.

Ingo Arndt / Sea trout (Salmo trutta trutta) alevin just hatched with full yolk sac, Europe

Laurent Geslin / Red fox (Vulpes vulpes) carrying Brown trout (Salmo trutta) found near a fishing pond, England

Linda Pitkin / 2020VISION / Brown trout (Salmo trutta) fry on river bed, Cumbria, England, UK, September.

Linda Pitkin / 2020VISION / Fisheries assistant Stephanie Kershaw and volunteer John Dumont at the Eden Rivers Trust electrofishing for juvenile Atlantic salmon (Salmo salar) and Brown trout (Salmo trutta) as part of a capture a...

Andy Trowbridge / Split level shot of a fly fisherman (Murray Trowbridge) releasing a large brown trout (Salmo trutta) in a gin clear 'backcountry' river, North Canterbury South Island, New Zealand. January, 2012. Mode...

Alex Mustard / 2020VISION / Brown trout (Salmo trutta) swimming through sun beams in a freshwater lake, Capernwray Quarry, Lancashire, UK, July

Linda Pitkin / 2020VISION / Brown trout (Salmo trutta) in turbulent water at a weir, River Ettick, Selkirkshire, Scotland, UK, October

Laurie Campbell / Brown trout (Salmo trutta) resting on river bed near the Aigas Field Studies Centre, Inverness-shire, Scotland, July

Linda Pitkin / 2020VISION / Brown trout (Salmo trutta), Ennerdale Valley, Lake District NP, Cumbria, England, UK, November 2011. Did you know? Trout scales have growth rings which you can read in the same way tree rings.

Kim Taylor / Brown Trout (Salmo trutta) juvenile jumping through the water surface to take a hoverfly. Surrey, UK.

Alex Mustard / 2020VISION / Silhouette of Brown trout (Salmo trutta) in freshwater lake, Capernwray, Lancashire, UK, July