It’s too loud in the Mediterranean: scientists present the first underwater noise map

Reblogged from the Tethys Research Institute website.


Human activities using loud noise sources cover very big portions of the Mediterranean Sea, as announced in a special press release by OceanCare. Their impacts on marine wildlife should be cause of concern; in several clearly identifiable areas noise-producing activities accumulate, and many of these so-called noise hotspots overlap with important cetacean habitats. This is a conclusion reached by scientists from France, Italy, Switzerland and the US who – for the first time – present a basin-wide map that shows the density of the main anthropogenic noise sources in the Mediterranean Sea. The results of the report ”Overview of the Noise Hotspots in the ACCOBAMS Area, Part I – Mediterranean Sea” for the period 2005 to 2015, are drawn from a dataset covering 1446 harbours and marinas, 228 oil drilling platforms, 830 seismic exploration activities, 7 million ship positions, publicly available information regarding military activities, and 52 wind farm projects.noise

 The increase in seismic activities is particularly striking, especially in connection with oil and gas explorations which deploy so-called ‘airguns’ sending loud impulsive noise of up to 260 decibels towards the sea floor about every 10 to 12 seconds for weeks or months at a time. While 3.8 % of the Mediterranean’s surface was affected by such airgun use in 2005, this share increased to 27 % in 2013. The scientists also found that an average value of around 1,500 commercial vessels are contemporarily present in the area – at any given time – not taking into account leisure crafts and fishing vessels. Considering that data surrounding military activities – such as manoeuvres, use of medium and low frequency sonar (LFAS, MFAS) for submarine detection, etc. are generally not available to the public, such results for this sector represents an underestimation of the reality of the situation as well.


Noise-cetacean interaction hotspots: overlap of noise hotspots and important cetacean habitats

Crucially, through such mapping exercise, the scientists were able to reveal several noise hotspots overlapping with areas that are of particular importance to noise-susceptible marine mammal species, and/or areas that are already declared protected areas. Such important cetacean habitats include the Pelagos Marine Mammal Sanctuary in the Ligurian Sea, the Strait of Sicily, and parts of the Hellenic Trench, as well as waters between the Balearic Islands and continental Spain where noise-producing activities accumulate, according to the report. The risk for the marine animals in such areas is thus high, as they are exposed to cumulative and synergistic noise, and hence, extensive sources of stress.

Such threat has also been recognised by the Spanish Government. Their Ministry of the Environment recently announced that the waters between the Balearic Islands and the Spanish mainland will be designated a protected migration corridor for whales and dolphins, which will also result in strict management measures for noise producing activities.

“This report is the first basis for a purposeful development of noise reducing measures. It substantiates the urgent need for action to establish a transparent data register on anthropogenic noise sources in the Mediterranean and to take measures to reduce the problem”, says Silvia Frey, PhD, co-author of the report and director for science and education at OceanCare. Implementing such a register is also part of the EU Marine Strategy Framework Directive’s current action plan.

“With this report, we stand at the beginning of an acoustic assessment of the Mediterranean Sea as a marine habitat. Thus far, only noise sources which are timely and spatially incomplete could be identified. Hence, there is further need for scientific investigations into noise levels within the Mediterranean and, moreover, into what can be assessed as an acceptable and safe noise limit. Nevertheless, this first glance is remarkable and the extent of the noise sources is worrisome”, explains Frey.

“The present mapping also reveals data weaknesses, as we have to assume that some areas currently identified as ‘quiet’, particularly along the coastline of Northern Africa, are only considered quiet due to a lack of data. In particular, activities by oil and gas companies, as well as the military remain largely obscure”, adds Nicolas Entrup, consultant on underwater noise pollution for OceanCare and for US-based organisation NRDC.

“For the first time we have a wide spatial and temporal vision of the multiple and often overlapping human activities that produce noise underwater and that may have synergistic and cumulative effects on marine life. We now need models to map sound levels and sound exposure. We should not forget that conservation also means ‘conserving the acoustic quality of the habitats’”, says Gianni Pavan, co-author of the report and professor of the University of Pavia, Italy.

“Loud noise sources appear to cover very big portions of the Mediterranean Sea, and, of course, their impacts on marine wildlife propagate, regardless of human boundaries. Although far from being exhaustive, results shown in this study point out the need of a regulatory framework which takes into account the transboundary effects of man-made noise on the marine environment”, Alessio Maglio, co-author and scientist at SINAY SAS, adds.

Manuel Castellote, PhD, co-author and scientist at NOAA, concludes: “With this report we have barely grasped the tip of the iceberg when it comes to underwater noise occurrence in the Mediterranean Sea. A major concern is the amount of silent Mediterranean countries, silent when it comes to information sharing, not underwater silence!”

The report was commissioned by the Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS) in order to identify areas of concern, to propose the need for further scientific assessment, as well as to deduce appropriate conservation measures.


More information:

Full report “Overview of the Noise Hotspots in the ACCOBAMS Area. Part I – Mediterranean Sea“

Short video ‘Underwater Noise – The Overlooked Catastrophe’ and the brochure ‘Drowning in Sound’.

Further information on the Silent Oceans Campaign:


a small victory for the whales

The US Department of the Interior, after campaigning by Oceana and its allies,  postponed their decision on whether to allow seismic airguns off the Atlantic coast, in an area where marine reserves, fishing grounds, and critical habitats for endangered species occurr. The encompasses more than 300,000 square miles of ocean from Delaware to Florida — an area twice the size of California!

Read more here, here, here and here.

Debate over seismic air guns should wait until science has spoken

(C) The Washington Post

By , Published: September 5


SEISMIC AIR guns are used to ascertain how much oil and gas lie under certain portions of the ocean floor. They’re towed behind ships that trace grids on the surface of the water, and they shoot blasts of compact air to the bottom of the ocean to track the reflected sounds. The problem is that those underwater blasts, at around 180 decibels, are louder than roaring jet engines, and they might harm ocean mammals, disrupting the feeding and migration patterns of whales, dolphins and other creatures.

In 2010, President Obama cleared the way for opening some 330,000 square miles of ocean off the East Coast, from the Delaware Bay to Florida’s Cape Canaveral, to exploration for oil and gas, of which there’s likely an enormous amount. As The Post’s Lenny Bernstein reported recently, the Bureau of Ocean Energy Management (BOEM) estimates that there are some 3.3 billion barrels of oil and 3.1 trillion cubic feet of natural gas off the East Coast, and those figures are based on data collected using outdated technology. The use of seismic guns has become a contentious issue among oil companies, conservationists and members of Congress since the Interior Department announced in March 2012 that it planned to allow them in the Atlantic.

In the Gulf of Mexico, a lawsuit over the use of the guns was settled in June with an agreement delaying their use for 30 months while officials further investigate their effects. But that same month, the House approved an amendment proposed by Rep. Scott Rigell (R-Va.) to require the BOEM to allow oil companies to test seismic air guns in the Atlantic as early as December. Proponents of the testing insist that the guns will find far more oil off the East Coast than is known to exist. In the gulf, seismic testing in 2011 revealed five times the oil reserves that had been detected by other methods.

Conservationists claim that using the guns off the East Coast would create a “war zone” for whales and dolphins. Some lawmakers, including Rep. Frank Pallone Jr. (D-N.J.) and the late Sen. Frank R. Lautenberg (D-N.J.), have complained to Mr. Obama that seismic air gun testing is only the first step toward a full embrace of offshore drilling.

The truth is that the battle is premature. Apart from the studies underway in the Gulf of Mexico, the government is updating its standards on noise levels that aren’t harmful to ocean life. The National Oceanic and Atmospheric Administration expects to complete them by the end of this year or the beginning of next. The risks of seismic air guns will be clearer then; only when science has spoken should any decision be made on their use off the Atlantic coast.

bubble curtains to save whales form ocean noise


Human activities, especially offshore oil and gas explorations, wind power structures and military exercises can confuse and harm even the mightiest denizens of the deep (see: turn down the volume in the oceansthe cuvier’s beaked whales saga; seismic surveys in the southern adriatic sea; underwater man-made sounds kill cetaceans; new atypical mass stranding of Cuvier’s beaked whales; new atypical mass stranding of Cuvier’s beaked whales – part 2Offshore wind farms may kill whalesOffshore wind farms may kill whales – part 2).

National Geographic in a recent article presents some new technologies that could potentially minimize and mitigate the impact of human activities on whales and other marine life.


If we were marine mammals, how would we feel in a very noisy environment? Simple, like having a bucket on our head! Check out the new dontbeabuckethead website.