A good emergency heat source can be made with 3 tea candles in a 1 lb coffee can. It puts out so much heat that you can't hold your hand over the can. Those little candles are very cheap and will burn up to 4 hours. It will literally take the chill off of a small tent if the drafts are kept to a minimum! Keep in mind the tent needs to be vented and the base needs to be on a flat rock. I have often worried after a close call years ago about carbon monoxide in tents as it happened to me. I think this is reasonably safe and start off small maybe one or two candles. Never use jelly alcohol or your stove. You do not want to burn off the oxygen. This is just to warm up the tent - 4 hours is enough in most situations - let it go out. In the morning it would help getting changed. A back up idea is to put the tea light on your stove tripod in a can off to a side where you wont bump it. Be careful out there.
Why question the intentions of a road-crossing chicken?