Maritime transport & Marine protection and restoration

Marine protection and restoration

Marine protection and restoration can be approached from a geographical angle (area-based approach), from a particular species angle (such as whale conservation), or through more encompassing ecosystem health approaches (reduction of pollution, etc.). 

Key international initiatives have been developed, both globally at EU level (Marine Strategy Framework Directive [1], EU Mission: Restore our Ocean and Waters [2]) that both frame EU actions in terms of marine protection and restoration, and at a more local level (such as the ACCOBAMS).

One of the main tools for area-based marine conservation is Marine Protected Areas (MPAs), but other designations fulfil similar functions (such as Natura 2000 areas). There has been a tenfold increase in MPA designation around the world since 2013.

Governance wise, this hugely diverse sector is divided between a wide range of actors of very different natures: States, NGO’s, local authorities, scientific institutions, international organizations, etc. It is therefore sometimes challenging to identify the relevant players that need to be involved in discussions.

Maritime transport

Maritime transport includes shipment of goods and transport of passengers by sea. It remains the backbone of international trade, with the EU being one of the most important exporters and exporters worldwide.

In terms of infrastructure, maritime transport not only requires seagoing vessels, but also ports as central logistics hubs, rendering the sector intimately connected to land-based infrastructure and relying on a complex web of land-sea logistics chains. The governance of the sector is also split between leading global shipowners (MSC, MAERSK, CMA-CGM) and smaller competitors. 

Ship routing systems have been established by the International Maritime Organisation (IMO) in congested shipping areas of the world for safety reasons. To minimize potential environmental impacts of shipping, the International Convention for the Prevention of Pollution from ships aims at minimizing pollution of the oceans and seas. In addition, maritime transport is expected to meet increasing sustainable performance criteria linked to key Sustainable Development Goals (SDGs) and notably SDG 14.

Maritime transport is a well-established sector, with a post-covid increasing demand for goods but also in vessel size and number. This growth puts increasing pressure on the marine environment and can often put important ecosystems at risk, notably through greenhouse gas emissions, air pollution, underwater noise, oil pollution, and the introduction of non-indigenous species [3].

For more information about EU blue economy sectors please visit the EU Blue Economy Observatory website. 

For more European statistics and data you can also visit the Eurostat website

Noise pollution

Maritime transport is the primary contributor to underwater noise pollution in the ocean [4]. Underwater noise and vibrations affect numerous marine species in several different ways. Marine mammals are especially affected as it interferes with their ability to transmit and receive acoustic information. Anthropogenic noise can change marine mammals' behavior and cause them to feed less or to produce fewer calls. Shipping noise also creates stress that links to poor immune system function and lower fertility, potentially having consequences on the population number of the species. 

Noise pollution also disrupts mammal’s ability to navigate as some sounds (military sonars for example) are so aggressive that cetaceans try to escape it.

Moreover, it must be noted that the amount of noise generated varies by vessel type: large vessels for example tend to create louder noise with low frequency, which has the potential to be propagated for long distances. Additionally, the shape and functioning of the propeller, as well as the speed of the ship also corelates to the noise emitted (the higher the speed, the higher the noise).   

The overall underwater noise from shipping in the EU has been estimated at 8000 million Joules in 2019 [5]. A more easily understandable figure is that a cargo vessel emits around 190 decibels of noise, which is louder than a jet engine taking off, estimated at 150 decibels (possibly causing eardrum rupture)[6].

Accidental spilling of hazardous substances and loss of containers

This category encompasses both the accidental discharge of hydrocarbons and oils spills into the ocean, as well as the accidental loss of containers into the ocean. Vessels can pose a threat to marine biodiversity through accidental spillage of oil and hydrocarbon as has been seen in the past in several highly publicized cases in western Europe (shipwrecks of Amoco Cadiz, Erika, Prestige, etc.). The release of accidental discharges of large quantities of oil can have major environmental impacts to a wide range of species, causing damage to coastal and marine environments and affecting sectors such as tourism and fishing. Moreover, aside from oil spills, vessels can pose a threat to marine biodiversity through accidental discharge of hazardous substances or through the periodic discharge of waste waters into the marine environment. Additionally, container ships sometimes accidentally lose containers at sea because of difficult weather (creating rolling and pitching) or improper stowage. The nature of the containers being diverse and varied, ranging from cars to hazardous chemicals and more, they can cause local pollution.

Exhaust emissions

It is estimated that approximately 3% of global carbon dioxide emissions can be attributed to maritime transport. This amount is comparable to major carbon-emitting countries: if this sector was a country, it would be the sixth largest producer of greenhouse gas emissions after the US, China, Russia, India and Japan [7]. Additionally, nitrogen emitted by ships contributes to the decrease of air quality, which indirectly affects biodiversity.

Collisions between marine mammals and vessels are known as “ship strikes” and mostly affect large cetaceans such as whales. This challenge is related to the noise pollution described above, as such strikes can occur due to high density maritime traffic, but also due to increased anthropogenic noise. This noise creates subsequent possible hearing problems in whales leading to their inability to avoid the vessels. Collisions may seem rare but are often not detected, so the problem is most likely underreported. Some key figures put light on the scale of the problem: According to the International Whaling Commission (IWC) [8], the number of definite and probable ship strikes worldwide between 1820 and 2019 is approximately 736 [9]. In 2019, a total of 23 strikes have been reported by the IWC [10]. In France only, between 1972 and 2017, a total of 51 ship strike incidents were identified, making it the first identified causes of mortality for large whale [11]. Ship strikes of cetaceans are an issue of growing concern internationally and are likely to represent the main fatal threat to whales on a global scale. In the Mediterranean basin, collisions with large vessels present a major conservation issue for fin whales (Balenoptera physalus) and sperm whales (Physeter microcephalus) especially in the western basin. Vessel speed also plays an important role in the frequency of collisions as well as their lethality. Collisions between vessels and whales at speeds of 14 knots or higher have a more than 60% possibility of being fatal; a probability that rises to 90% if the speed is equal to or higher than 19 knots. The International Whaling Commission (IWC) noted that the number of reported strikes between ships and whales has increased in recent years and that it is probably due to the increase in maritime traffic. 

Vessels can negatively affect marine ecosystems and associated benthic species through the use of their anchors. The size of the vessel and hence of the anchor play a role in the magnitude of this impact, with effects most pronounced in the case of coral reefs or other fragile habitat structures such as seagrass. Moreover, in shallow areas, bottom sediment is resuspended, with impacts associated with turbidity to surrounding benthic communities. 

Wastewater such as ballast water can also contribute to the release of invasive species. It has been estimated that yearly, more than 3,500 million tons of ballast water are transferred by vessels around the world, which greatly increases the problem of invasive species. Among all the ship types, tankers tend to use the largest ballast water quantities, followed by container ships. These “imported” species affect the ecological balance of their new locations by outcompeting native species or negatively impacting native ecosystems. When new species are introduced to non-native ecosystems, the interspecific competition (competition between two different species for the same resource) intensifies. If native species are outnumbered by invasive species, it affects the established predator-prey relationships and the trophic chain within that region. 

This challenge is indirectly linked to the coexistence of maritime transport and marine protection and restoration but must be noted. Ports are expanding in response to larger vessel sizes and numbers, and the development of ports and their expansion exerts different pressures on the natural environment. Such pressures occur in the initial construction phase with extensive dredging of the area, which impacts the surrounding environment, as well as with subsequent maintenance dredging, which is necessary for safe operation of the port. Both forms of dredging can remove important benthic biota, increase water turbidity, including the possible release of contaminants and heavy metals from within sediments and contribute to the decline of water quality. All these negatively affect marine habitats and associated species. Other pressures such as port illumination can also have negative impacts on biodiversity.

Protect specific biodiversity hotspots through legislation

The first option used to mitigate the potential adverse effects of maritime transport on marine life is the creation of protected areas with high ecosystem value where specific regulation concerning human activity such as shipping applies. As the level of protection can range from simple declarations to extensively regulated areas, several different management tools can be implemented with various intensity in the restrictions: Marine Protected Areas (MPAs), Particularly Sensitive Sea Areas (PSSAs), Special Areas (MARPOL) Natura 2000 area, Emission Control Areas (ECA), etc. A relevant example is the Pelagos Sanctuary for Marine Mammals, where a transboundary Specially Protected Area of Mediterranean Importance (SPAMI) was established with the aim of protecting marine mammals from anthropogenic activities occurring in the area by imposing specific restrictions on human activities such as maritime transport.

Developing sea basin maps of areas with high ecological values

Sea basin maps depicting areas of high ecological value and protected areas (MPA’s for example) greatly help in planning shipping routes. Such maps provide detailed insights to the most vulnerable species and habitats and can therefore be used to minimize the impacts caused by boat traffic and consequently shipping accidents and oil spills.

Designating specific anchorage areas

In areas outside ports where ships wait to load or unload their cargo, anchoring can have an impact on the local environment and traditional activities of indigenous communities. To reduce problems related to anchoring, such as habitat destruction, it can be helpful to designate dedicated anchoring areas or permanent moorings away from ecologically sensitive areas. This can be a good measure to protect vulnerable ecologically valuable marine areas. Additionally, anchorage areas close to ports could also be linked with other, non-spatial measures, such as rules for disposing of wastewater and other ship-based waste, as exemplified by the European project “Blue Ports”.

Designing new shipping routes or re-route shipping lanes

The designation of alternative routes for shipping could be an effective strategy to avoid ecologically sensitive areas and reduce potential harm to the overall health of ocean ecosystems. The TANGO project that took place in the Baltic Sea and more specifically in the Kattegat (the strait between Denmark and Sweden) is a good example of this phenomenon [12]. A major shipping lane was replaced by a complementary new one, originally to reduce the risk of collisions. But this change of route allowed scientist to track changes in underwater noise patterns and their effects on the local species.  The results eventually showed that rerouting shipping lanes has considerable effects on the marine ecosystems and that therefore, re-routing shipping lanes is one way to reduce the effects of underwater noise on the marine environment [13]. 

Involving stakeholders of both sectors in developing joint solutions

As explained previously, both the shipping sector and marine protection/restoration activities have complex governance models and scattered players. All relevant actors should be involved in developing joint solutions to mitigate the impacts of shipping on the marine environment. Agreements can be thought of between shipping companies and MPAs or other authorities to jointly implement good practices, as exemplified by the Green Marine Europe certification. Additionally, increasing awareness and training efforts for the general public but also notably for vessels’ crews is important as without their understanding of the problem and compliance, even the most advanced technologies will not resolve the issue. Tools that inform and engage stakeholders may help to improve compliance with mandatory and voluntary measures that are implemented to protect vulnerable species and populations. It also must be recalled that a significant part of maritime transport takes place on the high seas where few states regulations apply. This calls for a more international framework such as the setting of the United Nations Convention on the Law of the Sea (Montego Bay, 1982) and initiatives such as the adoption by the United Nations of the first treaty to protect the high seas (2023) [14].

As part of developing maritime spatial plans, speed restrictions in waters under national jurisdiction could be agreed around ecologically sensitive areas to reduce the impact of underwater noise and that of ship strikes. As explained in the section dedicated to the risk of collision with large cetaceans, vessel speed plays an important role in the frequency of collisions as well as their lethality. Moreover, the decrease in ship speed also significantly decreases their noise emissions. It is estimated that  Therefore, this measure could decrease both the frequency and lethality of collisions as well as the acoustic noise. Certain MPAs already impose speed restrictions on ships; some even have a complete ban on navigation. In fact, speed restrictions, especially seasonal speed restriction, can greatly reduce risks. Agreeing speed restrictions would require key stakeholders to work together with IMO and related parties; MSP could provide a platform for such collaboration.In the Pelagos Sanctuary [15], A code of conduct for marine mammal watching has been adopted. It requires ships to adopt a steady speed, not exceeding 5 knots, to match the speed of the slowest animal [16].

To address the problem of noise pollution generated by the shipping industry, shipping companies together with relevant stakeholders and the IMO are promoting the use of ship-quieting technologies. Advancements in corresponding new technologies such as quieter propellers have been developed and can be installed on new and existing ships. For example, in 2017, the shipping company Maersk modified several of its ships by installing new, more efficient propellers and reconfiguring hulls; such modifications resulted in a 75% reduction in noise energy emitted from the ship.  Alongside technical innovations, international acoustic standards have been published notably by the European Union Marine Strategy Framework Directive, as well as in the IMO non-mandatory guidelines.

Some software systems are designed to help reduce the risk of collision between large cetaceans and vessels. Vessels equipped with those tools can note each sighting of large cetaceans to a centralized server, which then sends out an alarm to other ships equipped with similar devices that are likely to encounter the cetacean. Such systems (REPCET software) are used by several vessels periodically navigating inside the Pelagos Sanctuary for example and could be implemented in more vessels through strategic partnerships between interested MPAs, the IMO and maritime transport companies.