Most guys build ponds with steep banks, 3:1 or even 4:1 slopes. That's hard on GSH. Not much shallow area for them to take cover in and not much flooded vegetation for them to spawn in. The ponds I have seen with the best long term survival of GSH are ponds with some shallow areas(less than 18").
I have never tried the fry method for stocking GSH, so I have no experience there. I think there is a lot to learn. Some studies should be done to see where the fry should be stocked into the pond. Shallow areas or out in the middle where it is deeper? Since GSH spawn in shallow areas, it would seem to me that the fry would do better in shallow areas but it is hard to tell until some studies are done...
Another important factor is if there is a good zooplankton bloom occurring when the fry are stocked. No bloom, and your fry will die or have such a slow growth rate they will be easy pickings.
Personally, I think the stocking of advanced adult GSH just prior to spawning is going to be a better way of getting GSH to take hold in an established pond. If only a dozen adult fish survive, they'll be producing millions of fry. Fry that are not in shock from being in a plastic bag for several hours and released into a pond. A new pond with only FHM and sunfish present, the fry option may be a cheaper and better option.
I have been able to establish GSH into ponds with adult predatory fish by stocking advanced sized GSH. GSH 6"+ in length. The bigger the GSH the better.
