Thanks, everybody! We'll be building the 'Hen Pen' (aka, temporary housing in our wellhouse until the coop is built) hopefully in the next few days! We've decided to put the brooder inside it, on the ground, with the doors open, so they can sleep under the lamp if they want, or if they don't, they don't have to.
Okay, this sounds silly, but are any of your chicks afraid of the dark? When I turn off the lights at night, without the brooder lamp on, they stuff themselves in the corner and chirp for several minutes. How could they be cold? Only a few seconds ago they were absolutely fine, and now they act like the temperature's dropped thirty degrees! Do they just not like the dark?