The 9/11 terrorist attacks on the World Trade Center and the Pentagon were absolute tragedies, taking the lives of nearly 3,000 innocents that day. However, recent research has revealed that there was a silver lining to that incredibly dark storm cloud. Whales around American waters were reportedly far less stressed after the attacks, and now researchers are explaining why.

No, whales don't hate America or freedom. They simply miss their peace and quiet, and in the weeks following the 9/11 attacks, they finally got it back.

Due to security concerns following the attacks, a great deal of nonessential boat traffic was halted around the United States, leaving North American coastal waters relatively free of motor noise and radar pings.

Now, a study published in the journal Proceedings of the Royal Society B has revealed that wild right whales were far less stressed than normal around this quiet time, and that more characteristic stress levels returned once boating traffic picked up again.

"Here is the first solid piece of evidence that says there's a link between noise level and stress," Christopher Clark, director of the bioacoustics research program at the Cornell Lab of Ornithology, who was not part of the research, explained to The Associated Press.

The researchers determined this after looking at records of stress hormone concentrations in whale droppings around the Bay of Fundy, encompassing five years before and after the attacks. The data was finally gathered, analyzed, and compared with acoustic studies of right whale chatter in the bay in 2009, and a strong correlation between stress, degrading right whale health, and man-made sound in the bay was drawn.

Since then, experts have been  working very hard to find other examples of how "sound pollution" is harming whales. Nature World News has previously reported how experts believe that whales sing songs not only to stay together, but to call in the pod for supper and even to recognize one another. It can then be understandably stressful for whales to live day-in and day-out with the incessant background noise of motors and sonar interrupting conversation.

Experts have even recently looked into the mechanics of how exactly baleen whales hear their songs so well, even while deep underwater. This could one day help conservationists manage ocean traffic to ensure that these majestic giants of the ocean deep get the quiet they deserve.

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