I put the Coturnix outside finally a couple days ago after keeping them inside for a week or so, they are supposed to be right around 4-5 months old. After I put them in the new setup in the small metal shed 6ftx 4ftI put a thermometer in there and with the 25mph winds we have had for two days it was a chilly 30 degrees in the shed. I felt sorry for them so I put a 100 watt heat light above them, the top 3 cages get the most warmth but I guess the bottom 3 will get the residual warmth. I kept the 100 watt "spot" bulb ( its all I had ) on overnight and it must have been pretty warm because their water didnt freeze and all my outdoor pens of chickens and pigeons had frozen water. I checked this morning and the temp in there was about 40 degrees. This morning I went ahead and picked up a 250 watt heat bulb and put it in the socket, I left that on a couple hours and rechecked it and it was up to 50 or so and the birds are up and moving around more, I also picked up a bunch of dead grass and made little nests in the back of each cage for them and they seem to be cuddling up in that pretty well. I know I read on here that most people just protect them from drafts and no heat, I just felt sorry for them after keeping them in my 70+ degree house for a week them putting them out when a cold snap is hitting.