Brown Trout Identification Guide

Key identification features

• Golden-brown to olive body, paler on the flanks and silvery in fish that have spent time in lakes or the sea
• Round black spots, often with pale halos, scattered on the head, back, and upper sides
• Scattered red or orange spots along the lateral line, usually also haloed in pale blue or white
• Tail fin has few or no spots, unlike heavily spotted trout species
• Adipose fin often edged in orange with a few dark spots

Common look-alikes

• Rainbow trout: shows a broad pink to red lateral stripe and dense black spotting covering the entire tail fin, both absent or minimal in brown trout
• Brook trout: has a wavy vermiculated pattern on the back and white-edged lower fins rather than round spots on a golden body
• Atlantic salmon: more streamlined body, spots are typically X-shaped or irregular rather than simple round black dots, and lacks red spots

Where you'll see one

Native to Europe and western Asia but widely introduced worldwide, inhabiting cool rivers, streams, and lakes, with sea-run forms migrating between fresh and salt water.