“. . . any introduction made for aquaculture must be thought of as a potential addition to the wild fauna in the receiving country.”
              R. L. Welcomme, FAO, 1988
A quote from R.L. Welcomme states that any introduction made for aquaculture must be thought of as a potential addition to the wild fauna in the receiving country.  The keyword here is potential. Not always is that going to happen, but the potential can be there.