Guys from Tionesta up river you start to lose the Flathead population big time, by the time you get to Warren you out of them, for some reason the flats will not go that far up, Kinzua Reservoir has no Flatheads I have done a lot of gill netting and studies out of that lake and never ever caught one Flathead in the Lake. Up river from Kinzua alot of studies clear to Port Allegany and never seen one in that area either, Lots of Channel cats have been stocked in the Allegany River and Kinzua Reservoir.
I think you will find from Tionesta up stream you will most likely catch Channels. I lived up there for several years and never seen a Flathead except below Tionesta.
Fishgeek: his boss has caught a few of them up there but not very many, not like they are down river into the mouth of the Ohio River.