So the cons of gshad are that they get bigger than predators can eat and over time will destroy your fishery by robbing nest of eggs.
There are several cons of gshad. They are not nest egg robbers. Their biggest issue is they reproduce so fast and their young growth so fast, that one, they overpopulate taking up a large percentage of the biomass in a pond. A major reason why even if they are stocked in a trophy bass pond, that pond should be at least 5 acres IMO. With their growth rate, they often outgrow their predator's mouth gape in a matter of a month or two. Large numbers of gshad compete with the young and often even middle sized game fish for food as they feed heavily on zooplankton.
The pros are that they create an outstanding forage base for a few years with the ability to provide larger prey to large predators.
Gshad provide good forage for a very short period of time to most predators other than large LMB, say over 18" or SMB over 22". That is one big SMB! Gshad and SMB really don't mix...
Will golden shiners be able to sustain themselfs if allowed ample time to inhabit the pond before say perch and smb are added?
This answer to this question is, it all depends... However, if conditions are favorable, then yes it is very likely golden shiners can maintain a self sustaining viable population in a SMB, YP pond... GSH need areas of shallow water with flooded vegetation to spawn and to use as a nursery for their YOY. Without this, their reproductive success rate will be very low and they will steadily be eaten out of the pond. Stocking golden shiners in advance of stocking particularly the SMB and allowing them a chance to establish and get some size to them, could help in getting them established. SMB are far less piscavorous than are LMB. Another important factor is not allowing the SMB and YP to overpopulate. If they do, they will over predate their forage a well.
What else could be added that would be a sustainable forage? I've heard that pumpkin seed reproduce to fast for smb to keep up with. Res wouldnt survive our winters.
As you mentioned, you're too far north for RES so they are not an option. Species that I feel could work well in a SMB, YP perch pond are: golden shiners, bluntnose minnows, fathead minnows, spotfin shiners, lake chubsuckers and orangespotted sunfish. Also don't forget that most good SMB ponds have at least a fair percentage of rocky areas. These areas should be utilized for stocking crayfish. SMB love crayfish and will readily feed on them.
