Brook Trout

Identification

The brook trout is a beautifully colored fish of 20 to 40 cm with a distinctive marbled pattern on the back and dorsal fin — wavy, worm-like light green markings on a dark background. The flanks show red spots with blue halos. The pelvic and anal fins have a white leading edge followed by a black stripe. It is not a true trout but a char, related to the Arctic char.

Behavior & ecology

Originates from North America, where it lives in cold mountain streams. Requires very clean, cold, oxygen-rich water (ideally below 16°C) and is more sensitive to pollution than the brown trout.

In the Netherlands

Does not occur naturally and has only been occasionally stocked in some cold streams in southern Limburg. With only 30 records, extremely rare. No self-sustaining populations are known. It potentially competes with the native brown trout and is no longer actively stocked.