One thing that is synonymous with baits that tend to attract catfish is the way they smell. Nearly all catfish baits have a strong smell that is not pleasant to humans. One of the most effective -- and most unpleasant-smelling -- baits is shad guts. The entrails of larger shad seem to draw bites from catfish when no other baits can. Properly rigged, shad guts catch catfish of all sizes.