That's true. It is very loud. I believe today that crews must have biologists on board monitoring marine mammal activity in the area and that acquisition must s

That's true. It is very loud. I believe today that crews must have biologists on board monitoring marine mammal activity in the area and that acquisition must stop when animals enter the area. There are also seasonal prohibitions on activity in most areas to allow mating and calving. This is not enough and it doesn't address the louder sounds from submarine communications which are most likely to be the reason for most mammal groundings today. It is better than it was in the 70's and 80's though. People learned and they adapted, though not always willingly.