If you are using a swamp cooler instead of Refrigerated air in your house with salted Deer-Hide or bird skins, the moist air will soften and ralax a salted skin and will start gettin smelly and if in zip lock bags that are slightly opened or out of the bag.....
I just REsalt em really good or Borax will or should do the trick.....does for me anyway.
I have noticed that some Squirrel Tails if not dried good will get real bad smelly