Donald has been missing in Turkey since October 2010.
He intended to return to a spot that a Chinese expedition had claimed to have found Noahs Ark in October 2009 - somewhere near the peak of Ararat.
He has been in the army, was allegedly well-equipped and has previously fasted so in theory, provided he has sufficient water, could survive for 50 - 60 days with no food.
The food he had could have lasted him a while, so it is possible he became stranded high up, seriously injured but still alive.
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