Catfish feed primarily through their sense of smell and they have a distinct taste for shad in any body of water that is home to both fish. Catfish anglers are missing out on a big trade secret if they don't match the hatch by fishing with cut shad during the time that shad runs are on and catfish are feeding beneath them.
Shad can be heard and seen busting the top of the water in lakes and rivers where they stage big spring runs. At times shad will be all over the place running to and fro and wise anglers who will be looking for catfish watch them.
During their runs, shad are attacked by a host of predators including many hungry birds, as well as gorging largemouth bass, striped bass, and, yes, catfish. The chaos of a spring shad run is a sight to behold as critters from above and below try to bust in and grab a shad dinner.
All of this means that shad are being wounded during their runs. Bits and pieces of wounded shad filter down in the water column at the lakes and rivers and catfish naturally enjoy the harvest.
A good shad run is like ringing the dinner bell for a catfish. Even if a catfish doesn't snag a whole shad it can gulp down a hearty meal on the leftovers that the other feasters leave behind.
That's why you will find big catfish underneath schools of shad. Not only are they eating the shad, they are also picking up all the bits and pieces the birds and fish dropped while devouring their shad buffet.
The trick is to get hold of a shad. You can often do this by fishing for them with various small jigs and bucktails. In some places you are allowed to use a cast net to capture shad. Once you have a fresh shad in your hand you have a bait no hungry catfish can refuse.
Most anglers fish cut shad on a fish finder rig. You have to have the bait on the bottom, so big weights may be necessary. In heavy current egg sinkers of one ounce or more help you keep your cut shad where it needs to be.
Catfish will find your cut shad bait if you leave it under a school of running shad. They are there just waiting for dinner. If that's what you're after too, then using cut shad to catch catfish makes fishing simple.