Ask Fish and Game
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Q. Why can you take 10 brook trout, but only 6 trout?
A. Brook trout are an introduced species that is very prolific and competes with native trout for food and habitat. Reducing the competition is the objective of this limit. Actually, the rule is "ten in addition to the trout limit" so if your first six trout were brook trout, you could be going home with 16 of them altogether.