Better check the regs on crossing state lines.
There are rules for all sorts of livestock, fish even, so I bet birds better be certified healthy and you better have a certificate in your hand.
Why not look for a place in the State you're heading to for you pheasants. Kills two problems at once, keeping them alive on the drive and the inspection deal.
If you do transport them, I'm with Aces. You better feed and water them. Birds have high metabolisms and will at a minimum need water. They may be pretty lethargic at the release site if you don't feed them also.
