Where did my crappies go?
And no lakes of any real size close by - especially that aren't flowage/reservoir lakes.
Location really changes in reservoir-type lakes between winter and spring.
If it was one of the little lakes in the area,those small waterbodies can really take a hit from fishing. If you weren't the only guy who was fishing them and the fish were all concentrated - say,in the deepest part of a small basin - then they COULD have (almost) all gone to hot grease heaven.