Crappie can be sampled very easily with a small mesh long-handle dip net, a very low cost tool. This time of the year it is easy to reach out and scoop along a pond bank to catch fry, as they will be feeding in very shallow water. Then one must be able to identify small crappie. I should have some crappie fry about now. Maybe I'll try to get some pics.

Also, remember, small crappie are good forage for large crappie AND HSBs. So a good crappie spawn isn't the end of the world, as long at the population of adult crappie and HSBs are large enough to take advantage of crappie offspring. To make this work to your advantage, stock the initial crappie after their spawning season, say late April/May. That way you don't get a quick spawn from the small initial stocker crappie, which might lead to quick problems. Still, these are theoretical predictions.

It's ALL about the fish!