Types of Trout and How to Identify Them

by Gaogao

The family of Salmonidae or “salmonids” include 45 species of salmon, trout, chars, and whitefish found in North America. Three genera within the Salmonidae family, Salmo, Salvelinus, and Oncorhynchus contain highly sought after types of trout species targeted by anglers from around the world.

It is important for anglers to know how to correctly identify their catch. This guide is designed to aid you in identification of the most commonly sought after trout species. When identifying trout it will be important to notice body coloration, fin color and shape, and the color and size of spots or vermiculations on their sides, backs, and fins.

brown troutbrown trout
brown trout photo by Nick Loveland / iNaturalist

Brown Trout (Salmo trutta)

  • Brown to yellow brown in color (vibrant orange colors during spawning season)
  • Black spots with margins and red spots with white margins
  • Adipose fin has a red margin with red spots
  • Anal, pelvic, and pectoral fins orange to yellow in coloration
  • Few to no spots on tail
  • Develop a bluish hue over the gill plate
  • 9-14 anal fin rays
  • Slightly forked caudal fin
  • See the full Brown Trout Species profile
brook troutbrook trout
Brook Trout photo by Henrique Pacheco / iNaturalist

Brook Trout (Salvelinus fontinalis)

  • Dark green back with stretched blotches
  • Spots on the side of the fish are yellow and red with a blue halo
  • Side profile fades from a green into a yellow or red lower quarter (vibrant during spawning season)
  • Belly is silvery white
  • Anal, pelvic, and pectoral fins are red with a white edge
  • 9-13 anal fin rays
  • Stretched blotches on tail
  • Slightly forked caudal fin
rainbow troutrainbow trout
Rainbow Trout photo by Kyle Nessen / iNaturlist

Rainbow Trout (Oncorhynchus mykiss)

  • Olive green back fading into a silvery green side profile
  • Black spots on sides, back, and top fins without margins
  • Spots are found throughout the caudal fin
  • Reddish-pink coloring can be present along the side and gill plate
  • Belly is silvery white
  • 10-12 anal fin rays
  • Slightly forked caudal fin
  • See the full Rainbow Trout Species profile
cutthroat troutcutthroat trout
Cutthroat Trout photo by Nick Loveland / iNaturalist

Cutthroat Trout

Formerly clumped into Oncorhynchus clarkii, as of 2023 there are now four recognized species. Coastal Cutthroat (Oncorhynchus clarkii), Lahontan Cutthroat Trout (Oncorhynchus henshawi), Westslope Cutthroat Trout (Oncorhynchus lewisi), Rocky Mountain Cutthroat Trout (Oncorhynchus virginalis)

  • Green back fading into a silver green side
  • Black spots generally towards the back half of body
  • Orange slit under the lower jaw
  • Can have yellow-orange anal, pelvic, and pectoral fins
  • 8-12 anal fin rays
  • Slightly forked caudal fin with various coloration and black spotting
Lake troutLake trout
Lake Trout photo by Allan Harris / INaturalist

Lake Trout (Salvelinus namaycush)

  • Dark brown to silvery green body color
  • Cream colored spots/blotches along body and fins
  • Anal, pectoral, and pelvic fins lighter brown with faded white edge
  • Deeply forked caudal fin
  • 8-12 anal fin rays
golden troutgolden trout
Golden Trout photo by J. Dreier / iNaturalist

Golden Trout (Oncorhynchus aguabonita)

  • Golden yellow body color with slightly green back
  • Black spots on the top and back portion of the body
  • Dorsal fins and caudal fin spotted
  • Around 10 parr marks along the lateral line
  • Reddish pink stripe down lateral line and gill plate
  • Anal, pelvic, pectoral fins orangish with white and black tips
  • 11 to 12 anal fin rays

 

Bull Trout (Salvelinus confluentus)

  • Darker greenish-grey body with lighter belly
  • Light to orange spots along body
  • No markings on the dorsal or caudal fin
  • Dorsal, adipose, and caudal fins dark
  • Pelvic, pectoral, and anal fins lighter with white edge
  • 8 to 11 anal fin rays
tiger trouttiger trout
Tiger Trout photo by Steven Merkley / INaturalist

Tiger Trout (Salmo trutta × Salvelinus fontinalis)

  • Cross between Brook and Brown trout
  • Body color ranges from yellow-brown to deep orange
  • Covered in wavy tiger-like markings and blotches
  • Do have markings on the caudal fin
  • Faded white edges on pelvic and anal fins
  • 9-13 anal fin rays
speckled sea troutspeckled sea trout
speckled sea trout photo by Evan Grimes / iNaturalist

Spotted Seatrout (Cynoscion nebulosus)

  • Actually it is not a Salmonidae species it is a Sciaenidae or drum croaker
  • Dark grey to green back with white belly
  • Dark round spots with white margins
  • Pair of canine teeth on upper jaw
  • Second dorsal fin instead of adipose
  • Square caudal fin with black edge
  • Jaw extends to back margin of the eye

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Steven BardinSteven Bardin

Steven Bardin

Steven Bardin obtained his bachelor’s degree in Freshwater Biology from Tarleton State University in 2009 and his master’s degree in Fisheries Science from Texas A&M in 2013. While at Tarleton, Bardin worked for Harrell Arms at Arms Fish Farm and Bait Company. In 2011 he founded Texas Pro Lake Management. He strives every day to take a scientific approach to helping his clients maximize the production of their fisheries.

Outside of TPLM Bardin has written for Wired2Fish, taught as an adjunct professor for Tarleton State University, and served as an instructor and camp coordinator for Bass Brigade youth leadership camp. In 2021, Bardin helped Major League Fishing found their Fisheries Management Division and leads their conservation efforts today.

Bardin is a member of Texas Aquatic Plant Management Society, Texas Chapter of American Fisheries Society, Southern Division of American Fisheries Society, Society of Lake Management Professionals, Texas Freshwater Fishing Hall of Fame Board, Texas Brigades Board, Texas Freshwater Fisheries Advisory Committee, and the Major League Fishing Anglers Association Board.

You can follow him on Facebook and Instagram.

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