As if humans weren’t already doing enough to destroy the planet and harm our fellow creatures, a new study has revealed that human-caused noise is hindering the ability of dolphins to communicate with one another.

Dolphins ― highly intelligent and social animals ― use a complex array of whistle calls to talk to each other that some scientists have compared to human speech.

But in a study published this week in the journal Biology Letters, researchers found that bottlenose dolphins in an area off the Maryland coast made their calls less complicated when noise created by shipping lanes and recreational boats was present.

Wild Horizon via Getty Images A mother Atlantic bottlenose dolphin and her offspring in Curacao.

“It’s kind of like trying to answer a question in a noisy bar and after repeated attempts to be heard, you just give the shortest answer possible,” marine biologist Helen Bailey of the University of Maryland Center for Environmental Science said in a news release. “Dolphins simplified their calls to counter the masking effects of vessel noise.”

Bailey’s assistant, Leila Fouda, added, “The simplification of these whistles could reduce the information in these acoustic signals and make it more difficult for dolphins to communicate.”

The researchers, who gathered data by putting microphones on the ocean floor, noted in the study that while it’s possible for ambient noise to occur naturally, the noise they recorded underwater was “mainly” caused by ships.

Their findings echo another study also published this week. Japanese scientists found that humpback whales around the country’s Ogasawara Islands are reducing their famous whale songs in response to noise caused by passing ships. And, as the site Inverse notes, a 2016 study on orcas also found that sound from ships hindered their communication abilities.

Bailey said in the statement on the dolphin study that people designing ships need to start taking the environmental impact of sound more seriously.

“We need to be working to engineer quieter boats,” she said.