JD,
Some others with more knowledge than me can chime in here, but having some adult shiners that are temporarily above forage size will produce more forage for your bass by spawning. Even the adult shiners will eventually become forage as the bass get larger. On the negative side, there have been posts indicating that goldies are known egg eaters (so are many other fish). I'll be interested to see other posts on this topic as I have not introduced goldens to my pond but am considering doing so.
