LIDO Acoustic Research (8:00) Although the negative effects of underwater noise pollution may seem straightforward, scientific data is limited indeed. Researchers use hydrophones (microphones designed for underwater use) to collect new data in deep waters, up to thousands of metres below sea level. An array of such devices can also be used to locate the source of any sound nearby. Arrays deployed on the sea bed create an acoustic observatory that does not interfere with marine life, compared with using ordinary listening devices aboard a ship. It also allows for continuous access to data.
Such acoustic observatories have been installed as part of the European demonstration mission called LIDO (LIstening to the Deep Ocean environment). The sound data collected is sent to onshore laboratories via optical fibre cables. Sounds made by whales and dolphins can be heard in real time, with a range of several kilometres. LIDO is coordinated from the Laboratory of Applied Bioacoustics in Vilanova i la Geltrú, near Barcelona. It is here where all the sound data is analysed. The sound data is sent from eleven acoustic observatories across Europe that together are known as ESONET (the European Sea-Floor Observatories Network).