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Have you ever heard a dolphin shout?

Well new research from the University of Bristol suggests they do just that to be able to communicate with each other as the ocean they live in gets louder and more noisy.

Dolphins rely on whistles and echolocation to hunt and communicate with others of their kind.

But human activity like drilling and shipping is leading to increasing underwater noise levels which could be putting the health of wild dolphins at risk.

During the study, scientists observed two dolphins - called Delta and Reese - in a body of water called a lagoon.

The scientists placed special recorders under the water that could capture the sounds they make while the pair completed a task they had set up there.

At each end of the lagoon was a button under the water which Delta and Reese needed to press at the same time (give or take a second) to succeed.

Researchers looked at how long it took for the dolphins to press the buttons at the same time with different levels of noise playing from an underwater speaker.

The results showed the dolphins' success rate was much lower when the noise levels were high, which suggests the impact noise levels have on the marine animals.

But scientists also noticed the dolphins compensated for this.

Compensating is when you put in extra effort into to make up for the loss or failure something.

In this case, the dolphins changed their volume and length of their calls to overcome the louder noises around them.

The animals changed their body language so that they could face each other and be closer together.

Experts say there's been a big increase in the amount of human-made noise around the globe, including in our oceans.

The study shows us that even though dolphins are trying to overcome the noise levels by adapting the way they communicate, it still impacts their success.

In the wild this would have consequences like dolphins struggling to find food or a mate.