Humans are already doing enough damage to our planet through greenhouse gas emissions, plastic waste, illegal wildlife trade and much more. Now a new study suggests high ambient noise in the ocean is harming the vocal calls of dolphins, preventing them from communicating with each other the way they used to.
We can almost see dolphins as sea people because they are extremely intelligent and social animals. They use ultrasound to communicate with one another, creating a complex array of whistle calls. Their communication skills are often compared to human speech, and it’s no secret that dolphins look extremely social in their interactions with humans, whether it’s in the wild or in a human-made habitat.
However, a new study published this week in the journal Biology Letters suggests high ambient noise in the ocean is hindering their communication skills. The study says bottlenose dolphins living near the Maryland coast are making less complex sounds when noise from shipping lanes and recreational boats is present.
“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.”
To listen to the vocal calls of dolphins, the researchers gathered data by placing microphones on the ocean floor. They noted in the study that even though ambient noise can occur naturally, the noise that ruins the vocal calls of dolphins was created by ships, meaning that this issue is caused by humans.
“These whistles are really important,” Bailey said. “Nobody wants to live in a noisy neighborhood. If you have these chronic noise levels, what does this mean to the population?”
The findings of the new study come in the wake of another study that was recently published. A group of Japanese scientists discovered that humpback whales living around Japan’s Ogasawara Islands are reducing their whale songs due to high ambient noise in the ocean from ships.
Bailey also said in the statement about the dolphin study that people who design ships should understand the impact of the noise their ships cause and redesign them so they don’t have such a negative impact on dolphins.
“We need to be working to engineer quieter boats,” she said.