Walter Wirth has tons of little bullheads. Channels are silver or grey. They will bite for most of the year but get preoccupied with their spawning. Like most catfish they go for a spot that has some good cover, submerged structures or fallen trees. Rocky outcroppings as well. They just hold tight to those spots. Always target those areas first, then hit up deeper, slow pools. The largest bullhead and channel I have seen came from the Willy. Do some searches through the forum. You will find some good reading in there!!