Last year I caught a good sized (14") Smallie above Cherry Run in early April and have caught a few other times in the early spring on Penns. So I would guess they are around in small numbers any time of the year and not just in the warm weather season. Not a real big deal really since as stated above many trout streams have a small population of SMBs.I've caught smallmouth in Bald Eagle Creek below Milesburg, and in Kettle Creek in the special regs area. I've caught smallmouth in Penns Creek near the PFBC access above Cherry Run and have seen them as far up as the old rr bridge at Poe Paddy. In all these cases they appear to move up as the water temperatures rise. I don't think they are there year around.