First sign of trouble

I woke up this morning and found that one of the chicks was missing tail feathers.  I think that it lost them to either stress or being picked on by the other chicks.  The temperature in the brooder fell to 89 degrees overnight.  It should be at 95 degrees.  That could have added to the stress.  I hope this little guy pulls through, we'll just have to keep an eye on it and make sure the others don't peck him.