After much researching I have come to the conlusion that Game Wardens (Federal and State) may not enter your house without a search warrant. They may search your property without a search warrant. Lets put this urban myth to bed.
Jay, I am unaware of any special privelges granted to Game and Fish officers. I may be wrong. They should be operating under the same rules as did the rest of us in the performance of our duties. Unless they have probable cause, to enter a domicile, they really shouldn't enter. PC would include an emergency, or 'hot pursuit' or some such urgent matter, that cannot reasonably await a warrant.
There should be no 'search' of property, unless something amiss can be seen, then that can lead to a ''search''. If they obtain anything from ''searching'' with no PC or it couldn't be seen from a normal position, then it would probably be tossed as being found without cause.