Don't misunderstand me, I love the way that chickens can be both incredibly smart one minute and yet as dumb as a dishcloth the next, but when I moved the chooks water into it's trial winter location (over a small heater) I was amazed that the previous 7 months of knowledge disappeared in an instant! I only moved the blooming thing 3 feet, but no they moped about clearly not drinking anything. I had to 'teach' them what it was all over again (fortunately it only took a few taps to get them started again). The heater is a new idea to stop the water freezing and it's showing one or two degrees C at the moment, so I am doubting it will work once it gets properly cold (it's only -5 C at the mo). And yet the very same chickens found the only 6' section of wall on the outside of our home at ground level that has any heating on inside (at that level it's all storage or underfloor areas apart from a bathroom, living accom is 3 foot out the ground.) the wall must radiate a fraction of it's heat, although none that I could feel with my bare hands, but they congregate exactly there, smart huh? Chickens dontcha just love em!