Possible Clues:

• Freshwater varieties
• Fish in streams
• Game fishes
• Cutthroat, steelhead and rainbow, for three
• Rainbow and Dolly Varden
• Whitlings, e.g.
• Brookies and steelheads
• Rare plural for the freshwater fish Salmo fario
• rainbow or brown fish, optional plural
• Plural fish, speckled, rainbow etc