I have a friend who takes great pride in catching large smallmouth bass during the winter. He floats the smallmouth bass rivers in his canoe. He concentrates on the deepest sections of the large pools. An important part of the large basses diet at this time of the year are the real madtoms that live on the streambottom. He uses the Murray's Black Madtom Sculpin Streamer size 4 and Murray's Olive Madtom Sculpin Streamer size 4. He swims them slowly along the streambottom with great success.
The South Fork of the Shenandoah River has many of these deep pools downstream of Luray. The North Fork of the Shenandoah River had many of these deep poools downstream from Chapman's Landing.