Today on the radio I heard a news report about somebody being pulled from alligator infested water. It seems that whenever there is a water rescue or a plane goes down in water, it's alligator infested. Well, not always - sometimes it's snake and alligator infested. Unless, of course, it's in the ocean, in which case it's shark infested waters.
Reporters love to add drama, to use hyperbole. They don't really know much, especially about nature. A reporter's knowledge is a mile wide and an inch deep, a radio reporter once told me. If a body of water is a mile wide and an inch deep, it's snake infested. When something happens in a place with any semblance of being natural, it's always reported as being infested with whatever wildlife it may happen to be the natural habitat of.
When the county condemned our hoarder neighbor's house, the first thing they did was have it fumigated to kill all the rats. Now, that's infested! When reporters tell us about something happening in alligator and snake infested waters, that's their shorthand for shallow freshwater in the southeastern United States. When they say shark infested water, they mean seawater.