This is Scientific American's 60-second Science, I'm Susanne Bard.Large oceangoing vessels like oil tankers and cruise ships produce noise that travels long distances underwater.That audio pollution can disrupt the sounds that marine mammals, fish and other animals use to communicate."When there's lots of noise from ship traffic, it basically masks those sounds so they just can't hear each other."University of Exeter sensory ecologist Emily Carter.She wondered whether ship noise might also be detrimental to animals that don't rely on sound for communication.For example, young shore crabs that use camouflage to hide from predators."So they can actually change their color to match whatever it is that they're sitting on, basically to make it harder for predators to find them."Carter suspected that stress from ship noise might hinder the change process.To find out, she and her colleagues collected juvenile shore crabs with dark shells and brought them back to the lab.They placed the crabs in tanks full of white gravel.An underwater speaker in each tank played quiet natural sounds at all times.One group of crabs also heard loud natural sounds every hour. But another group was subjected to hourly recordings of large ships.Carter says shorebirds―which eat the crabs―can see UV light,so she used ultraviolet photography to determine how well the crabs blended into their new habitat over time.
