His chance of locating
a water hole on any given day is twice as
great as that of a normal character -- perhaps
the single most important
aspect of this skill.
This proficiency also includes foraging
skill; the character can locate a certain quantity of edible plants
in
half the time it takes for a normal character to obtain the same
quantity.
At the DM’s discretion, other advantages
may be afforded to a character with desert survival skills and to
the other members of his party. For instance, a proficient character
may be able to better endure a long stretch of time when no
fresh water is available - not because he can go without water
for longer than anyone else, but because he knows how to conserve
his supply.