I was joking about the white perch thing. You can catch them but not good eating unless you like bones. I know of some private ponds that have perch in them around Lincoln but good luck getting permission on those unless you know the owners well. Usually stocked for their pleasure. This side of the state doesnt have much for perch, game and parks seems to focus more on bass and blue gill in these parts. Iowa isnt far though and some to some good perch fishing plus their limits are better.
As for the ice at Branched Oak. Wouldnt even think of going there yet, even when we have good ice it still can be iffy out there if you dont know the lake well. Ask Eastwesterner about sending his friend for a swim night fishing a few years back.
All in all. The best perch fishing is out west, have to be willing to drive. And the drive is definitely worth it. Will be back up there for a few days over New Years.