An international group of scientists is calling for stricter regulations to protect marine wildlife from noise pollution. In a study published last week in the journal Frontiers in Ecology and the Environment, researchers argue that action is needed to tackle excessive ocean noise from industrial activities such as shipping and seismic surveys, which use loud sound pulses fired from compressed air guns to explore the sea floor and find natural resources.
(From Scientific American / by Emma Brown) — Nature asked two authors of the study, conservation ecologists Douglas Nowacek at the Duke University Marine Laboratory in Beaufort, North Carolina, and Howard Rosenbaum at the Wildlife Conservation Society in New York City, why this is such an urgent problem. This interview has been edited for length and clarity.
How does noise pollution harm marine life?
Douglas Nowacek (DN): One concern is hearing damage in animals. That can happen either with very loud sounds or over longer periods of exposure to lower levels of noise. Also, with air guns, the reverberations raise the background noise level and so risk masking animals’ communication and navigation signals. A final concern is stress. Short-term stress is not that big a deal, but long-term stress is really detrimental. It causes physiological and reproductive problems; and we don’t know a lot about how sensitive marine animals are to it.
Howard Rosenbaum (HR): Effects have been documented across a range of species, from bowhead whales in the Arctic and sperm whales in the Gulf of Mexico, to herring in the North Sea. There are still questions out there about what these impacts mean in the long term for individual animals or populations, but there’s an increasing body of evidence.
Don’t industries already have to take measures to limit possible damage to marine life?
HR: The requirements vary from region to region. In many places around the world, surveyors must slowly ramp up the air-gun strength at the beginning of a survey, to warn off animals in the area, but we really don’t know how effective this practice is. Surveyors might be required to limit their operations in areas where endangered animals are present or have been previously observed, and shut down if animals enter a certain zone. The overall benefits from many of these measures are still really unknown. We feel that more needs to be done to safeguard marine species and their most important habitats.
Read the full article here: http://www.scientificamerican.com/article/marine-life-needs-protection-from-noise-pollution/