India, March 13 -- Iran, which is currently all over the news cycle, is mostly a mountainous and desert country, bounded by the shallow Persian Gulf to its south. You would not expect a shark attack, of all things, to occur in Iran. But it is time to think again.

In the far southwest of the country, just above the head of the Persian Gulf, is the city of Ahvaz on the Karun river. The river flows into the Shatt al-Arab waterway formed by the confluence of the Tigris and Euphrates rivers in Al Qurnah, Iraq. The Karun has the highest amount of water and is the only navigable river in Iran. The Karun at Ahvaz is where bull sharks (Carcharhinus leucas) have attacked and killed people in the past.

These victims included Allied soldiers in Wor...