Why do flatheads migrate upriver? To spawn? To eat? or just seasonal migration? There is a fish ladder on the river which allows fish like shad and stripers to migrate upstream through the dams. There is a camera in the fish ladder which allows us to view it live. In the past 2 days, I've counted hundreds of flatheads migration upstream through the fish ladder. And these are not small fish either. My opinion of this is they go in there to feed because there is a plethora of food for them (shad, bass, suckers, carp, trout, stripers). Also, with all the fish moving upstream, how you you approach fishing this dam??? Would you fish below it??? or Would you fish above it???? I have never fish directly above a dam. Below the dam is very fast running water and snags (rocks and boulders). I never knew there were so many big flatheads here directly in the city of Philadelphia. Please help me get one before the PAFBC gets them before I do!!!