There's a Kind of Hush?

Scientists, using more than 230 non-military hydrophones (devices that pick up sounds in water), confirmed that 2020 was 'the year of the quiet ocean' (https://www.theguardian.com/environment/2021/apr/17/covid-pandemic-made-2020-the-year-of-the-quiet-ocean-say-scientists). The Covid pandemic resulted in much less noise pollution being generated in marine habitats. There was less noise from ship's engines, trawling activity, oil platforms, sub-sea mining etc. Noise pollution is known to disrupt many marine species, especially cetaceans (whales and dolphins). Low frequency signals, such as those generated by these human activities, can also travel thousands of kilometres in seawater. The scientists will use 2020 as a base-line, for accurately assessing the impact of marine noise pollution.