Josh, if you can find out your water temperatures, we should be able to determine if you should be seeing fathead minnows easily.

If not, then you are probably correct in that they didn't make it. Stocking while a pond is iced over probably has small chances of success.

I would explore getting a few pounds of fatheads to stock ASAP.

Excerpt from Robert Crais' "The Monkey's Raincoat:"
"She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."