A recurring problem in the Mediterranean, ship strikes between cetaceans and boats (fishing boats, ferries and cargo ships as well as racing boats and whale watching boats) are partly responsible for decreasing the size of the populations of large cetaceans that live, feed and breed in the area. These threats are also worse for populations that are small in number and/or isolated geographically.

Some species have been studied in greater detail than others, in part as a result of the collaboration established between researchers and shipping companies following the creation of the Pelagos Sanctuary. Thus we now know that for two species, while they rank among the largest on the planet, ship strikes are a threat: fin whales and sperm whales. Genetic studies have shown that these cetacean populations are isolated from those in the Atlantic and are thus more vulnerable. In addition, the fact that they are few in number and have a low birth rate means that the people who manage them must remain attentive with regard to the future of both species, which are already victims of other disturbances caused by humans. Lastly, these studies show that over 6% of the individuals at sea (identified from photographs) and more than 20% of stranded individuals show traces of ship strikes.

It has thus become imperative to map out where ship strikes are the most frequent, to design mechanisms and measures to reduce the risk of ship strikes in these areas, and to pursue scientific research to further the knowledge on these species and to adopt specific management measures.

In addition to this ecological consideration, ship strikes pose a safety problem for high-speed vessels. For ships, a ship strike with a whale at a speed of 30 or 40 knots can breach the hull and cause water to flow in. In recent years, this has occurred on a number of occasions along the routes linking the islands, to say nothing of sanitary threats, timetabling issues, costs of repair, and reputation risks that shipping companies face in the event of a ship strike event.

We should also note that the unregulated presence of whale watching boats around cetaceans can also lead to ship strikes with the animals. For example, thirty-two ship strike events with large cetaceans (sperm whales, killer whales and four mysticete species) were recorded around the world between 1984 and 2003 (IWC, 2005). Worse still, a ship strike event between a sperm whale and a high-speed ferry in the Canary Islands killed a passenger on board. The last two incidents however occur less frequently than collisions with ships. 

Management options

The scientific community and certain shipping companies are alarmed by these accidents, particularly within the Pelagos Sanctuary. It is for this reason that researchers and marine transport groups made a commitment to develop a program designed to limit the risk of ship strikes. Since this research and these partnerships began exploring ship strikes due to marine traffic in the Mediterranean, there have been results and solutions have been proposed by the French Party of the Pelagos Sanctuary. These focused, among other ideas, on:

  • organizing annual professional training (an annual professional training organized by Souffleurs d'Ecume association, is already implemented by the French Part of the Pelagos Sanctuary at the Ecole Nationale Supérieure Maritime (ENSM) in Marseilles;
  • conducting scientific studies: applied research (scientific monitoring procedures) as a means of learning more about large cetaceans;
  • drawing up maps showing areas in which there is a ship strike risk (click here to consult the most recent scientific study);
  • developing technological tools for use by shipping companies, as in, among others, the REPCET system (Network for the Real-Time Reporting of the Locations of Large Cetaceans);
  • having an observer on board passenger transport ships that travel through the Pelagos Sanctuary (the location of all sightings is recorded on observation forms);
  • using alternative routes, and reducing cruising speed.

The REPCET system, launched by the Souffleurs d'Ecume association, was approved by the Pôle de Compétitivité Mer PACA (Marine Business Cluster for the PACA Region) in June 2007 and aims at helping to reduce the risk (initially) of daytime ship strikes between boats making regular journeys and large cetaceans. REPCET uses the density of boat traffic in the Mediterranean to improve the detection of large cetaceans by boats on regular routes by means of a computer network. Other technological tools are also under study (Active High Frequency Phased-Array Sonar, sonar, light-enhancing binoculars, infrared).

Scientific research within the Sanctuary must continue, then. In order to be able to respond to the problems posed by boats and ships, the comparative analysis of the distributions (and their variations) of cetaceans and marine activities within the Sanctuary zone must be carried out and, in the future, a partnership with the shipping companies should be created.


In this section, we provide an overview of the knowledge acquired to date on the impacts of human activities on cetacean populations. These impacts are also the focus of management measures, which will likewise be described.

Underwater noise can de classified according to its source:

  • physical source: wind, storms, waves, turbulence, earthquake, seabed, icebergs etc.;
  • biological source: sounds produced by animals or as a result of their movement;
  • anthropogenic source: human activities (boats, geological exploration, military activities etc.).

A number of recent studies have shown that marine noise caused by marine traffic continues to increase. From 1950 to 2000, low-frequency sound doubled every ten years. The cause is related to the number of boats, which trebled, and their ever-increasing size.

While we need to remain particularly cautious in assessing the impact that noise has on marine mammals, a number of scientific studies provide accounts of behavioral changes.

Anthropogenic marine noise is a form of pollution that, while widely recognized, is almost entirely unregulated. We know that a number of species of fish and marine mammals are very sensitive to noise and use it to orientate themselves, find food, locate partners, avoid predators and communicate with each other. It has been shown, for example, that there is a relationship between the noise from human activities and bycatch and ship strike events, the noise preventing animals from detecting fishing nets and boats.

As we industrialize our seas, the problem of marine noise pollution is growing. A number of noise sources combine, particularly marine traffic, oil and gas exploration and production sites for these raw materials, dredging, construction work and military activities, and are the reason for the huge increase in noise levels in seas everywhere. In the last ten years, studies show that certain types of marine noise can kill, injure and deafen whales and other marine mammals as well as fish. In particular, there is a proven link between multiple marine mammal strandings and deaths and exposure to military sonar. It has also been shown that certain animals affected do not strand themselves but die at sea. Lastly, it has been found that intense noises have a damaging effect on various species of fish that are caught for commercial purposes, and notably results in habitats lost, limited reproductive abilities and a greater susceptibility to illness. One study even revealed that fishermen’s catches were reduced from 45 to 70% by the use of air cannons.

As with other types of pollution that require multilateral regulation, marine noise pollution is a cross-border issue. Major sources of marine noise, such as military sonar and marine transport, can be propagated over hundreds of kilometers.


Management options

The current level of understanding in relation to the issue of underwater noise is still too limited to enable adequate and effective management options to be implemented. However, in response to this growing problem, a number of intergovernmental bodies have acknowledged that marine noise constitutes a threat to the marine environment and are thus calling for the precautionary principle to be adopted when managing activities that create noise across the world’s oceans.

Regarding noise from marine traffic, a real-time mapping system has been conducted in French waters of the Pelagos Sanctuary and published online by SINAY in the framework of the National Research Program of the French Part to the Agreement.

While risks to marine mammals are believed to exist in the Pelagos Sanctuary, a consultative process concerning construction at sea, is in place within it. A request for works permits must first be filed with the supervising authority, which then refers to the concerned Part of the Pelagos Sanctuary for its opinion. This Part consults the specific groups involved, who give their advices on the issue.

Concerning military sonars, Italian Part of the Pelagos Sanctuary, has issued a unilateral proclamation that they will not use within the area.

Lastly, as regards seismic exploration (seeking oil and other materials) and the major risk of temporary or permanent deafness or damage to echolocation systems, the Pelagos Sanctuary as a SPAMI may give a negative opinion on this issue.

In October 2007, at the Third Meeting of the Contracting Parties to the ACCOBAMS Agreement, the participants made various recommendations for management measures relating to underwater noise:

  • Prohibiting the use of military sonar within the Sanctuary, especially because of the presence of Cuvier’s beaked whales, a species that is particularly sensitive to acoustic disturbances.
  • Prohibiting seismic exploration within the Sanctuary. Ensuring that large fin whale habitats are protected, as the species is known to be sensitive to this type of noise, but also to in order protect other species.
  • Creating a buffer zone to stop seismic noise, which would extend to the west, parallel to the Sanctuary, and offer additional protection to sperm whales.
  • Working with the International Maritime Organization and marine transport and ferry companies in order to change the routes of certain shipping lanes, so that they avoid species that are sensitive to such noise (and for whom there is a risk of collisions)
  • Carrying out new research into shipping lane routes. Monitoring boats’ movements using surveillance systems such as automatic identification systems and monitoring other acoustic activities using strategically placed passive acoustic monitoring buoys.
  • Encouraging the Permanent Secretariat of the Pelagos Sanctuary to enter into discussions with the marine transport companies operating in the area to persuade them to use noise-limiting technology on vessels.
  • Strengthening the current stranding network, enabling it to carry out autopsies that are deemed necessary in order to detect gas and fat embolic syndrome, lesions caused by ship strikes etc. (as well as training activities and the creation of a tissue bank).

For the record, it is worth noting that the issue was also the subject of a number of international recommendations issued by organizations including ASCOBANS (2003), IWC (2004), the European Parliament (2004), IUCN (2004) etc.

In addition, the Pelagos Sanctuary is a member of ACCOBAMS / ASCOBANS working group on anthropogenic noise. 

It is clear that the international community actively supports multilateral efforts to combat marine noise pollution, which is a dangerous threat to the marine environment. We believe that it is incumbent on the relevant UN groups, particularly the signatories of the United Nations Convention on the Laws of the Sea (UNCLOS), to build on this desire and lead the movement to investigate ways of regulating marine noise, which is polluting the planet’s oceans.

The use of motorboats (fishing boats, ferries, jet-skis, boats used in offshore activities and whale watching) at sea requires fuel, which creates greenhouse gas emissions that accelerate climate change.

At this stage, whale watching is largely still reliant on fossil fuels, something that is not particularly compatible with the idea of ‘sustainability’. First, from an economic perspective, due to the repercussions of increased oil prices. Second, from an ecological perspective, as 80% of whale watching boats are powered by diesel engines, which consume a great deal of energy and produce greenhouse gas emissions.

It is worth noting that these greenhouse gases contribute to rising sea temperatures. Northern krill, for example, which are the sole prey of fin whales, could face significant disruptions as a result of the increase in habitat temperature. Lastly, the particles produced by the combustion of fossil fuels at whale-watching sites could be the cause of respiratory problems for cetaceans. Further scientific studies now need to be carried out in order to implement the adequate management measures.

Management options

Studies across the ACCOBAMS are conducted to assess the impact of climate change on cetaceans and identify indicator species, in collaboration with international bodies such as the International Whaling Commission (IWC), the International Union for Conservation of Nature (IUCN) and the General Fisheries Commission for the Mediterranean (GFCM).

Standard for the monitoring of climate change in Marine Protected Areas in the Mediterranean indicators are also being developed in collaboration with IUCN.

It is also essential to choose alternatives to fossil fuels (renewable energies, new propulsion technologies ) and to test them within the Sanctuary, in collaboration with the inventors and distributors of these systems, as well as approved whale-watching operators. The eco-tourism activities offered should also be reorganized (e.g. limiting trips between the port and whale-watching sites) as a means of limiting energy consumption.


Pollution from hydrocarbons can affect marine mammals both:
- directly, causing poisoning and chronic irritation to sensitive tissue,
- indirectly by being ingested over time and asphyxiating species.
Further study into this subject is required.

Persistent organic pollutants such as PCBs (polychlorinated byphenyls), meanwhile, build up in the mammals’ fatty tissue. As predators, the mammals are often at the end of the food chain, so are likely to be more contaminated than other marine animals as a result of the bioaccumulation phenomenon. This large build-up of pollutants can have negative biological effects on cetaceans: physical weakness, reproductive problems.

Pesticides such as DDT also pose problems including malformation, cancer and other issues adversely affecting reproductive and immune systems, which can make animals more vulnerable and cause increased illness (as with morbillivirus infection, for example). Furthermore, these chemical pollutants are transferred through the fat-rich milk that mothers feed to their young when nursing.

Heavy metals (mercury, lead etc.) also cause physiological problems, mainly affecting the nervous system.

We should also note that there are other types of pollutants in the Mediterranean – urban waste and household liquid waste, which is sometimes untreated before disposal.


Management options

  • Implementing existing agreements and recommendations to fight marine pollution (RAMOGE Agreement, ACCOBAMS)
  • Manage and monitor areas
  • Environmental impact studies that include marine mammals
  • Water Framework Directive (WFD)
  • Marine Strategy Directive Framework (MSDF), etc.