Over the last couple of years we have seen several oscillations in the supply of live bait. At the start of the Pandemic supplies of live bait were low because of the increased number of anglers that were out of work and took up fishing again, using larger quantities of live bait than the suppliers had anticipated. This summer as the Covid craze lessened and people went back to work, retail suppliers couldn't make a profit on bait because stores were not ordering large quantities. During these periods when supplies were low, I was constantly being asked the question about what size live bait is best for the local species of fish. Some weeks the larger baits were available and at other times only the smaller bait was in the stores.
Actually the same question is consistently asked with regard to lures. Will a 14 inch bass attack a 4 inch lure? Like just about every subject related to fishing, there are many answers to these questions depending on who you ask and no answer is really wrong because there are many variables that effect the answer.
First let me say that if a Lake Norman fish is hungry, regardless of its species, it will attack almost anything that swims by as long as it is smaller than itself. The phots below was sent to me by a reader who caught this trout that was digesting this smaller trout half its size. While the fish was being digested, the trout actually attacked the anglers lure. That was a hungry trout.
We don't have trout in our lake but a bass, if hungry enough will attack nearly any fish that is smaller than itself. I have found that during the spring and early summer months when the water temperature is in the comfortable range between 60 and 80 degrees, every species in this lake prefers medium sized bait between 3 and 4 inches. As the water warms and when it gets very cold, bass will tend to want a larger bait knowing that they don't like to exert a lot of energy attacking their prey. Size of course is only one issue for the predators. Any bait or lure that acts like it is wounded or otherwise unable to swim away, will be a preferred meal for a bass.
Catfish also have a preference regarding live bait. Channel cats will attack smaller bait and often will like something that smells. Blue cats prefer larger baits with the really big ones wanting a sizeable chunk of bait. Flatheads like their food to be alive, no matter what size it is
With the situation being as it is these days when we never know what's available, I say take what you can get. Its better to be on the lake with the wrong size bait than sitting at home waiting for the right size to come along.