I have young guineas that can go in and out of their cope as they wish. They roost along the sides at night and even on their roosting stick inside their 'open air cope'. My question is at what temp should I add a heat lamp for them? or do I need to do this at all?? I live in Virginia just off the Blue Ridge Parkway and currently it is in the 60's at night.... Come winter I will close off three sides so the cold and dampness will be reduced and if it snows I will add a heat lamp for them but I am unsure for the current temps if they need that extra heat??? These younguns are varied in age...4 months thru 5 1/2 months... they all seem fine but I want to be sure I am doing right by them... I have ducks and a peacock too but the guineas are so much more fragile...or seem to be anyway. Thanks in advance!