John

Thirty buckets of dead fish sounds devastating. I'm sorry to hear that.

I have a 1.5 acre pond that had a very low density stocking of YP and SMB last Fall. I found one dead YP this Spring but have had no indication that there are any YP or SMB remaining and am worried that I may have had a winter kill and they mostly sunk to the bottom, therefore I didn't find floaters. Like you, I tried fishing at different times of the day, different weather, different bait presentations, etc without luck. If I could catch just one SMB and one YP, get a quick length and weight and release them, I'd be happy but so far no success. Given my very low density stocking and the prolific forage population, I expected that enticing something to bite may be difficult but I was hopeful that it was at least possible. They're either not there, or I'm a terrible fisherman. I hope its the latter.

The YP that were stocked would have been large enough to spawn this Spring but it's unlikely that the SMB were large enough to do so. Given this, I decided to try to trap YP YOY. Setting traps near structure, away from structure, varying the depth, time of day, bait, etc. led to traps full of forage and not a single YP or SMB.

Although both species are hardy, I've had no evidence that they are still in there so I'm moving forward with plans to restock (at a higher density this time and with twice the water volume).

Some things that are working against you is that the YP have plenty of places to evade you (your weed beds) and they have plenty of forage so enticing one to bite will likely take more effort than what it otherwise would. If you have a few minnow traps, give those a try. You should be able to get a survey of your shiners at the same time.

I tend to catch perch ice fishing in deeper parts of ponds, so sending a camera into the deepest part when ice fishing may reveal them if they are still there.

Depending on the sizes and numbers of your fish, carrying capacity of your pond may be a factor in your fish kill happening to begin with, but I'll leave that to the experts on here to comment on.

Keep us posted with your progress. I hope you find that they are just eating less this time of year, but a thriving population is still in there.