Hackback valves have become famous for their beautiful songs, but researchers have found that noise from ships is enough to…
Hackback valves have become famous for their beautiful songs, but researchers have found that noise from ships is enough to shorten their songs or stop singing altogether.
While sea noise has become a growing concern, which is expected to be increasingly influential in marine life, researchers from the Ogasawara Whale Watching Association and Japan’s Hokkaido University in Japan would see how noise from cargo vessels affected humpback whales living around the Ogasawara Islands.
They put underwater microphones in the area and identified one to three singers a day and a total of 26 singers. They concluded in a study published just in the PLOS One magazine that the behavior of these whales changed when ships were present and they either stopped singing completely or shortened their songs when a ship approached and they did even when ships were almost a mile away . They also found that most did not start singing again for at least 30 minutes after the ships had left.
Since only male humpbacks sang, did not see their work on how women and calves are affected, but it is difficult to imagine that they are not affected.
“There is a further evidence confirming that the sound people have a negative impact on all sorts of aspects of life in marine mammals,” said Spencer Fire, Associate Professor of the Florida Tech Department of Ocean Engineering and Marine Sciences, telling CNN.
Although he was not involved in the study, he added that the results were important because hard data could be used to change policies that would protect marine mammals from noise that adversely affect them by changing their behavior, disturbing them, causing them to use too much energy or force them into quieter areas where they may not find enough food.
Conservation people recently considered the issue at a summit held by the International Maritime Organization, where nearly a dozen organizations demanded a delay in speed speeds to reduce noise.
“Underwater noise from ships increases the levels of stress-related hormones in whales that can affect their ability to reproduce and impair their immune system,” Regina Asmutis-Silvia, Executive Director of Whale and Dolphin Conservation, told independent. “Because whales and dolphins are heavily dependent on sounds for communicating, navigating, hanging out and locating bytes, a noisy sea is where their field of” vision “shrinks, which requires that whales increase their conversational amplitudes.”
Not only would the ships lower the lakes quieter for marine mammals and reduce their stress levels, it would have the added benefits of reducing the risk of ship attacks and reducing greenhouse gas emissions.
Hopefully this study will contribute to further changes
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