To sample your BG spawn, just get a $10 - $12 minnow trap. Put some of your fish food inside a mesh bag, put it inside, tie a string on, and toss it into 2' of water. Let it sit overnight and pull it in. I was seeing 2" BG last August after stocking 3-6" adults in April.
Also, my fatheads from last April look to be all gone, at one time I had millions, but I have a heavy predator base.