Yep, you can catch some nice cats on fly rods. Especially the open water feeders like blues and channels. Cause despite what most folks think or claim they are less junk eaters (though they will) but more baitfish eaters like bass.
What winter flies are working for you all? I had a tank hit a rainbow warrior on Saturday. Had some little bitties hit a prince nymph with rubber legs as well. ( trout fishing)