Ferrets tend to be thirsty animals, particularly in summer, and it is essential that they have ready access to plenty of fresh, clean water. Some ferrets do not drink easily from drinking bottles so check to ensure the method is adequate. Instead of a bottle – or in addition - consider using a small tray. A small cat litter tray is cheap and ideal for the purpose. Place a brick in the tray to ensure it is not tipped over.
FACT - Ferrets deprived of water particularly in the summer will suffer dehydration and / or likely kidney failure both of which are likely to be fatal