Tell us about yourself!
My hat is off to you. your work is excellent. One tip on the electronics front would be to use a lower frequency crystal. The 16MHz crystal could be lowered to 1MHz or lower. This would decrease the current consumption dramatically. You can still use the software by changing the delays. My recommendation would be to use a Seiko 1MHz oscillator module which you can buy from Mouser or Digi-Key. These are tiny SMD parts. Simply feed the output of the oscillator to XTAL-1 of the MPU. There is no need to change the MPU's fuse settings when this is done. Again, fantastic job.
A different method is much easier and far less time consuming. 1, Buy a plastic ball from a toy store.2, Tightly wrap the ball with several layers of foil.3, polish using a rag and some metal polish. 4, Use it for something useful such as the top cap of a Tesla coil.
Great project, but good luck with the paint. PVC is almost impossible to paint. My guess is that your nice red paint will peel off the bird houses in a week or two at most. The birds won't care so all in all, you have done a magnificent job.
Thanks for the great tutorial. One thing though. You need to do some study regarding your preference for fat free foods. There is a lot of evidence that it is a disaster to your body to eat fat free. You may well be on the road to dementia when you get older. The body and brain needs fat to work properly.