My scientific response is the pre-spawn feeding frenzy starts when the Forsythia are in bloom. Well I don't really know when it starts but as long as the bass know, I will follow their lead. When I go fishing on Saturday, if the fish are biting, then it must be pre-spawn feeding. If they are not biting, it must still be wintertime fishing. I may be totally wrong but at least I keep my sanity and my ego that way.
Mike