ive got a batch of 6 runner ducklings who are now 5 weeks old yesterday. theyve been living outside with NO suplimental heat since 3 1/2 weeks old, but out temps have been pretty steady in the upper 70's to mid 80's during the day and in the 50's at night. they are doing fine, good eaters, active, silly..., belly and chest have actual feathers, as do under the wings and around the eyes, but their backs are still down. they have a small "house" (4ft long, 2 ft tall and 2 ft deep) with a 6" layer of shavings, and a small sheltered run attatched...so no worries about drafts and no worries about a huge shelter to try and heat...i knwo small spaces retain body heat better) Well tonight our temps are supposed to drop down to possibly as low as 36 degrees... Im just worried since there not completly fully feathered yet...despite being out for almost 2 weeks, is 36 degrees too low for 5 week old ducklings I have no way to run power to their house so if 36 is going to be too low for them im going to have to bring them in tonight which means setting the brooder box back up (and they will be MAD lol) but i dont wnt them to freeze to death either). the only water they have acess to IN the run is via a water bottle, so im not worried about them getting wet and chilled... Opinions? thoughts? whats "too cold" for 1/2 a dozen 5 week old runners?