My chickens are about 10 weeks old now and have been in their new coop for about 3 weeks. At dusk instead of getting on their roosts, they all cram in the corner of coop and fight and push for position. This pushing and shoving goes on for 20 or so minutes until they cease and settle down. I wonder why they do this and not roost? Is this just habit they are used to? The only thing I can think of is that I had them longer in their brooder than I should have and they got used to not roosting........ Anybody else have/had this problem?