A good bow finish should be fine without treatment, but a paste wax is good insurance to help protect the finish.
The biggest concern are any scratches or nicks that go through the finish. That is where the water can penetrate to the wood and then you have problems, so touch those up with nail polish first.
Also as has already been mentioned, takedown bows need to be taken apart and wiped down to keep water from getting into the limb bolt holes. Shouldn't be a problem while you are hunting, but make sure to dry it out when you are done.