I am curious about this heat intolerance for YP. I really do believe it is a limiting factor for several "cool water" species in more southern climates. Species like YP, TM, NP, WE and HSB all seem to stress out from heat less when they are smaller, but when they start reaching what one would consider trophy sizes, they cannot handle warm waters. I wish there was more data or research on what the cut off size for each species is... At what point do they hit that size and at what temp/DO concentration do they start to struggle. I have seen a good amount of research for HSB, but the others less so...
All I know is both Bill and I have found a few floaters in the 14 inch plus range when we get an extended heat wave although not too many. My strain is originally from Lake Erie and I believe Bill's are at least mostly from Lake Erie, so obviously they have not adapted to temps in the 80's to 90's.
There are yellow perch naturally as far south as North and South Carolina so it would make sense if they have evolved to be more temperature tolerant. CJ, I do wonder how many of these fish are brackish water fish where cooler water is found, but you would know more about that.
Another thing that causes fish to go belly up in Bill's pond is when Cecil Baird shows up. Don't ask me why but Bill can verify it. Perhaps the presence of a fish taxidermist scares them to death.
