Since we live in N GA the temps don't get too cold here - the coldest night so far this winter was 16 degrees. We used a red heat lamp for several nights in the coop while the temps were in the teens. Seems that the girls were irritable and pecked at each other more. So did the cold make them cranky or less sleep from the red light? Its getting colder again we're not going to use the heat lamp and see what happens. The girls seem happy - we're averaging 8.5 eggs a day from nine 8 1/2 month old hens. The coop is snug and has deep litter. Has anyone else observred cranky behavior when using a red lamp or do chickens not see red light?