You may be right. I am looking at the water temps. and 35 fow is TOO WARM for the likeness of perch. I just can't see this as being true also. Scratching my head, hoping someone has a reliable report soon. Was wanting to try tomorrow. Now, wait till Friday. Maybe grasshopper.
Over the years rearing fish including Yellow Perch I think food source is more important than temperature. I had brown trout coming up in 85 degree surface water to feed and go back down in the trout pond a couple of weeks ago. Fortunately I've cranked the well back up and max temperature on the surface is in the upper 60's. My yellow perch that I have grown to 3.26 pounds now, survive in my 9 feet deep maximum depth pond (average depth 7 feet) through the summer. If it really gets warm they slow down and sulk on the bottom but they survive. The stock originally comes from Lake Erie.