A new study has shown that sonar used in the military can be damaging to blue whales' hearing, the Guardian reported.

The research has connected naval exercises to mass strandings of whales and dolphins around the world. The deep-sea mammals flee from the sound made by sonar blips because it hurts their ears and, in some cases, confuse it for their own communicative calls.

"For whales and dolphins, listening is as important as seeing is for humans - they communicate, locate food, and navigate using sound," said Sarah Dolman, of charity Whale and Dolphin Conservation. "Noise pollution threatens vulnerable populations, driving them away from areas important to their survival, and at worst injuring or even causing the deaths of some whales and dolphins."

Beaked whales, like the blue whale and unlike the baleen whale, were shown to be most sensitive to sonar. Some instances showed blue whales to rapidly flee, even in the middle of feeding, when they heard the sonar.

The blue whale's population has declined by 95 percent over the past century.

"This result has to be taken into consideration by regulators and those planning naval exercises," said Stacy DeRuiter, at the University of St Andrews in Scotland.

In Southern California, researchers tested the effect of sonar by exposing whales to frequencies between 3.5 and 4 kHz, which is lower than the military's. The scientists placed suction cups on the whales to track movements and reactions upon hearing the noise. Not all reacted, but some abandoned food and fled the source of the noise.

"Whales clearly respond in some conditions by modifying diving behavior and temporarily avoiding areas where sounds were produced," study author Jeremy Goldbogen, of the nonprofit Cascadia Research Collective, said in a statement from Duke. "But overall the responses are complex and depend on a number of interacting factors."

The British Royal Navy told the Guardian that they limit their use of sonar around whales.

"We are committed to taking all reasonable and practical measures to protect the environment and mitigate effects on marine mammals," a spokesman said. "This new research will be taken into account in the regular review of MoD active sonar mitigation procedures."