It's a cruelty to animals.  They ship these poor birds in huge unairconditioned mail trucks, then rural carriers have to try to get these poor creatures to their shipping address.  They are not cared for in these huge unairconditioned trucks, passed on to rural carriers who if not for the sake that they'd lose their job would rather open the box and let them all go free.  It's pitiful. And this is not just small birds.  Read on...

http://pe.usps.com/archive/html/dmmarchive1209/C022.htm