Out of interest what is actually done to avoid them?
You put the inlet pillows in every night. But remember, most GOM heliports are in the swamp. Not *near* the swamp, IN it. And until you've seen how many little green frogs can hang on to the side of various structures, you cannot imagine how hard it is to ensure that one won't find his/her undetected way into your intake. GOM pilots preflight and untie in the darkness, to be ready for a sunrise takeoff.
In reality, they do little damage, other than causing a startling *POP!* and surge from the engine. Some pilots shrug and keep going on their way; others react harshly and put the thing down "off-airport" so to speak.