How do they get fresh water to drink?
Most of the land surface of Aldabra is ancient coral which has been raised above sea level. Rainwater trapped in coral hollows are often a place they would drink from I assume. It is said that the Aldabra tortoise has a nasal cavity shared by a cartilaginous valve/membrane (which separates the inhaled water from the air being inhaled) and that allows it to drink through its nose.
You may have noticed that Aldabra tortoises have very pointy noses. There could be a tablespoon of water ... in a curled leaf or small depression in a rock, they can poke their pointy nose there and suck it up through their nostrils.
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