Rainbow Trout
Tulumnes; Wikimedia Commons / EOL (CC BY-SA) · CC-BY-SA

Rainbow Trout

Oncorhynchus mykiss

trout
  • Look for a broad reddish or pink stripe running along the side of the fish from behind the gills all the way to the tail — this is the most distinctive marking.
  • The pink or red lateral stripe is brightest and most vivid on breeding males, which can help you identify the fish's sex in the field.
  • Coloration can vary widely depending on whether the fish came from a stream, lake, or ocean — stream fish tend to be more colorful while ocean-run fish (steelhead) may appear much more silvery.
  • Adult fish can range from small stream-sized fish around 1 lb up to much larger lake or ocean-run individuals reaching 20 lb, so body size alone won't identify this species — always check for the side stripe.