Don't know if anyone posted this tidbit yet:
There is a product that mountainbike riders have been using that is perfect for hunters.
It's a small backpack that contains a collapsible water container. The water is accessed thru a flexible hose, hence no stopping or movement to drink! The original company who designed this is called CamelBax. Their website is www.camelbax.com. Any bike shop should carry a line of different models.
They even have camo and "ninja" black verisons!