Brook Trout

Trout and char

Salvelinus fontinalis · also called brookie, speckled trout, squaretail

The brook trout is a char rather than a true trout, which is why its markings run the opposite way — light on dark instead of dark on light. The white-edged fins are visible from several feet away and settle it.

Quick facts

Appearance
Dark olive-green with pale worm-like squiggles across the back, red spots ringed with blue halos on the flank, and white leading edges on orange lower fins.
Typical size
0.2–3 lb
Waters
stream cold, lake
Regulations
Native brook trout populations are declining and many streams have protective limits, gear restrictions or full catch-and-release rules.

How to confirm it

  • Pale worm-like vermiculations across a dark back — light markings on dark, the reverse of trout.
  • White leading edge on the pectoral, pelvic and anal fins, backed by a black line.
  • Red spots surrounded by blue halos.
  • Square tail, giving it the name squaretail.

What it is confused with

One check settles each of these.

Brown trout has dark spots on a light body. Brook trout has light squiggles on a dark body and white-edged fins.

Rainbow has a fully spotted tail and no white fin edges.

Why this matters beyond curiosity

  • Look-alike species often carry different limits. Walleye and sauger, black and white crappie, pike and muskie, blue and channel catfish — each pair can have different sizes, seasons and daily limits in the same water.
  • Check it before the fish goes in the livewell. Most of the tests on this site take seconds and are far easier on a fish you are still holding.
  • If you cannot tell, release it. That is the answer that is never wrong, and it is the one a warden will not argue with.
  • Regulations are set by your state or province and change annually. This site identifies fish; it does not tell you the rules. Check the current regulations for the water you are on.