This chart divides fish and shellfish into groups by texture and flavor, and will help you find substitute species that can be interchanged in recipes.
Mild Flavor
Moderate Flavor
Full Flavor
Delicate Texture
Cod
Crabmeat
Flounder
Haddock
Pollock
Scallops
Skate
Sole
Black Cod
Butterfish
Lake Perch
Lingcod
Whitefish
Whiting
Bluefish
Mussels
Oysters
Moderate Texture
Crawfish
Lobster
Rockfish
Sheepshead
Shrimp
Tilapia
Walleye
Pike
Orange Roughy
Canned Tuna
Conch
Mullet
Ocean Perch
Shad
Smelt
Surimi
Trout
Canned Salmon
Canned Sardines
Mackerel
Smoked Fish
Firm Texture
Catfish
Grouper
Halibut
Monkfish
Sea Bass
Snapper
Squid
Tautog
Tilefish
Amberjack
Drum
Mahi-Mahi
Octopus
Pompano
Shark
Sturgeon
Clams
Marlin
Salmon
Swordfish
Tuna

source: National Fisheries Institute

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