It seems like Scott69's results are somewhat similar to yours.
I'm really unsure if you had a LMB spawn or not. Many say that bass can spawn very early especially when at low quantities in a larger body of water.
What size were the 3,000 bluegill when you stocked them?
I know without a doubt a I had a spawn in 2016, as I saw the fingerlings swimming the banks. The 3000 bluegill were 1-3". Remember, those were stocked in Jan of 2015, 6 months prior to the fingerling bass.
