Rainbow Trout and Similar Species
Oncorhynchus mykiss
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Open the appSeveral fish can be confused with Rainbow Trout. Here are the key differences.
Species often confused with {name}
Cutthroat Trout
Oncorhynchus clarkii
Key differences: Cutthroat Trout typically have a red or orange 'cutthroat' mark in the fold of the lower jaw, which Rainbow Trout lack. Cutthroat Trout often have larger, more irregularly shaped spots, and their caudal fin is typically less forked and may have fewer spots. Hybridization between the two species (cutbows) can make identification challenging.
Brown Trout
Salmo trutta
Key differences: Brown Trout typically have fewer, larger, and often haloed spots (red and black) on their sides, with fewer spots on the caudal fin. Their body coloration is often more golden-brown. The adipose fin of a Brown Trout is typically orange or reddish, whereas a Rainbow Trout's is usually spotted and darker.
Brook Trout
Salvelinus fontinalis
Key differences: Brook Trout are char, not true trout, and belong to a different genus. They have distinctive worm-like markings (vermiculations) on their back and dorsal fin, red spots with blue halos on their sides, and white leading edges on their pectoral, pelvic, and anal fins. Their tail fin is typically square or slightly emarginate.
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