A critically endangered population of long-finned pilot whales living in the Strait of Gibraltar (the narrow waterway connecting the Atlantic Ocean and the Mediterranean Sea) is being forced to dramatically alter its communication because of shipping noise, according to a new study published in the Journal of Experimental Biology. Researchers from Aarhus University in Denmark attached acoustic tags to 23 whales between 2012 and 2015, recording over 84 hours of audio; they found that the animals called less frequently during periods of heavy ship traffic and raised the volume of their calls by roughly half the increase in background noise — effectively shouting to be heard. The findings add to a growing body of evidence that underwater noise pollution poses a serious threat to marine life, prompting scientists and policymakers to explore solutions such as quieter ship designs and rerouted shipping lanes.