I believe crawdads will eat anything. They would prefer live caught fish, insects, or live plants, but will settle for the dead as a second option.
The ONLY crayfish allowed in Mo is the northern (Orconectes virilis).
***EDIT***The only crayfish allowed to be sold in Missouri is the northern NOT the only one allowed in Missouri. I would suspect trouble if you got caught using something else for bait.****
My ~60 year old pond was only two foot deep when I purchased the place (filled in with muck) and had absolutely NO plant life. I thought the thing was contaminated. But, you could throw out a trap and catch many many small crawdads in an hour, hundreds in a day so long as you upped the bait occasionally. This explained the absence of vegetation as water quality checks proved the pond in good order with the exception of slightly basic water. I bucket stocked some creek fish and with a year or so the crawdads could not be caught, but you could get plenty of GSF. My first lesson in the GSF. They wiped out the crawdads and some vegetation started to show up. Mostly FA. Once the pond was drained it became evident that a dozen GSF can produce about 1,000 in two summers Anyhow, I digress! It's what I do.
