Fisheries & Maritime transport

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 [2].

Fisheries

Fishing has a long history in all European sea basins, and is of particular importance to coastal communities, both economically, socially, and as a food source. 

Capture fisheries have direct and indirect impacts on the marine environment and ecosystems notably through removal of biomass. However, thanks to innovations and regulations put in place over the last few decades within the EU, the state of fish stocks is progressively recovering [3], and conservation measures are expected to result in stock rebuilding.

The sector is regulated by the Common fisheries policy (CFP) [4], that aims at sustainably managing European fishing fleets and conserving fish stocks. Additionally, the Marine Action Plan aims at keeping fish stocks to sustainable levels and reducing the overall impact of fishing [5].

The sector is still facing major challenges and it has been in constant decline in volume for more than 20 years. This is largely due to the sensitivity of the business to the cost of fuel oil, reinforcing the need to decarbonise the sector as quickly as possible. 

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

Over the last century, human activities in and near the water have increasingly added artificial sounds to this environment [10]. Underwater noise generated by maritime transport contributes to an increased level of noise in the ocean. Underwater noise and vibrations affect numerous marine species in several different ways.

Most fish and invertebrates use sound for vital life functions. Very loud sounds of relatively short exposure, such as those produced during pile driving, can harm nearby fish. However, more moderate underwater noises of longer duration, such as those produced by vessels, could potentially impact much larger areas, and involve much larger numbers of fish⁸. Noise impacts on development include body malformations, higher egg or immature mortality, developmental delays, delays in metamorphosing and settling, and slower growth rates. Stress impacts from noise are also not uncommon, including higher levels of stress hormones, greater metabolic rate, oxygen uptake, cardiac output, parasites, irritation, distress, and mortality rate [11]. At the same time, schooling can become uncoordinated, unaggregated, and unstructured due to noise. Feeding patterns and foraging, reproduction and spawning and predation and alarm systems can be affected by noise as fish rely on sound to navigate their environment, find food, reproduce, and avoid predators. In fact, some commercial catches can drop by up to 80% due to noise, with larger fish leaving the area. Bycatch rates also could increase, while abundance generally decreased with noise. Once the population biology and ecology are impacted, it is clear fisheries and even food security for humans are also affected. Noise impacts should be incorporated into population modelling for fish.

_{Figure 1. Hearing ranges of selected fish and mammal species, reflecting some of the typical variety in these taxonomic groups (From Slabbekoorn, H., et al., (2010) [12])}

Moreover, it must be noted that the amount of noise generated varies by vessel type and size: 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 use dynamic positioning systems in ships is also associated with the generation of potentially damaging noise levels. 

Accidental spillage of hazardous substances

This category encompasses the accidental discharge of hydrocarbons and oils spills into the ocean. All vessels can pose a threat to marine biodiversity, and thus the fisheries that target it, 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.). 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. Oil spills can cause serious damage to fishery resources through physical contamination, toxic effects on stock and by disrupting business activities. The nature and extent of the impact on fisheries depends on the characteristics of the spilled oil, the circumstances of the incident and the type of fishing activity or business affected. The greater impact is likely to be found near-shore, where animals and plants may be physically coated and smothered by oil or directly exposed to toxic components over extended periods. In some cases, effective protective measures and clean-up can prevent or minimise damage [13], however, fishing and harvesting restrictions are usually imposed after an oil spill in order to prevent or minimise contamination of fishing gear and to protect or reassure consumers, with the consequent economic costs to fisheries.
 

Aside from oil spills, vessels can pose a threat to marine biodiversity, including fishery resources, through accidental discharge of hazardous substances or through the periodic discharge of waste waters into the marine environment.

Collisions between fishing vessels and maritime transport ships, although unlikely, can occur due to human error or manoeuvres that result in one vessel crossing in to another´s lane [14]. Management measures should also tackle this challenge in order to avoid increasing numbers of reported strikes between merchant ships and fishing vessels in view of the likely increase in maritime traffic. 

Vessels can negatively affect marine ecosystems which play a key role in the lifecycle of commercially important fish stocks 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 fragile habitat structures such as seagrass or biogenic reefs. Moreover, in shallow areas, bottom sediment is resuspended, resulting in increased turbidity and associated impacts 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. Many invasive alien species highly impact fisheries in European Seas. However, even though mostly negative impacts are reported in the literature, many alien species can have important positive impacts and can restore or secure ecosystem processes and functions, especially in degraded ecosystems. These negative or positive impacts occur through a variety of mechanisms such as blooms of toxic algae, the degradation of important habitats, predation, competition, fouling shellfish, gear or equipment, damage of catch or fishing gear, entanglement in nets, disease transmission, new commodities, new food source for commercial species, biological control of other invasives, and creation of novel habitats. The balance between positive and negative impacts is difficult to assess, and in many regions alien species are considered as a benefit to fisheries. In some regions, climate change has caused the loss of temperature-sensitive species. In such cases, alien species can be beneficial overall by fulfilling the lost ecological roles or even providing new sources of income to fisheries [15].

Illegal, unreported and unregulated (IUU) fishing refers to fishing which is carried out without proper authorization. This can undermine national, regional and global efforts to conserve and manage fish stocks and result in poor safety and working conditions for fishers. Illegal, Unreported and Unregulated (IUU) fishing has important implications for navigational safety and sustainable maritime transport as it mostly occurs offshore and in international waters [16].

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. Of particular relevance to fisheries, all sources of significant noise should be prohibited from biologically important areas (e.g. spawning grounds, nursery areas, important foraging habitat) and times of year, such as spawning [17]. These areas should be managed with noise in mind, including acoustic buffer zones. However, as the level of protection can range from simple declarations to extensively regulated areas, 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. 

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 local 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 for commercially important species of fish. All noise sources should avoid biologically important areas (e.g., spawning grounds, nursery areas, important foraging habitat) and times of year, such as spawning. Dawn or dusk ‘fish choruses’ should preferably also be avoided. A recovery period for females immediately after spawning should be allowed, as females tend to be in very poor body condition at this time. Acoustic refuges of still-quiet biologically important areas for noise-sensitive marine life should be safeguarded and protected from noise. Shipping lanes could be rerouted to avoid important fish and invertebrate habitat [18].

Imposing ship speed restrictions within certain areas

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.  The decrease in ship speed significantly decreases their noise emissions. It is estimated that for each 1 knot in speed reduction, a ship’s noise is reduced by 1 decibel. Certain MPAs already impose speed restrictions on ships; some even have a complete ban on navigation. In fact, speed restrictions and in particular 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.

Use ship-quieting technologies

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.

All sonars, echosounders, and multibeams should use frequencies above at least 200 kHz. At the same time, there is a need to promote and further develop airgun alternatives and quieting technologies, such as Marine Vibroseis, which is thought to lower particle motion acceleration as well. Also work to reduce vibration through the seabed.

Similarly, in order to reduce commercial shipping and fishing vessel noise (e.g., dragging) through technological innovation or quieter operation (e.g. slow steaming). Ships should avoid routes immediately parallel to the continental shelf as noise can more easily enter the deep sound channel, travelling very efficiently for large distances [19].

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.

All sonars, echosounders, and multibeams should use frequencies above at least 200 kHz. At the same time, there is a need to promote and further develope airgun alternatives and quieting technologies, such as (Marine Vibroseis), which is thought to lower particle motion acceleration as well. Also work to reduce vibration through the sea bed.

Similarly, in order to reduce commercial shipping and fishing vessel noise (e.g. dragging) through technological innovation or quieter operation (e.g. slow steaming). Ships should avoid routes immediately parallel to the continental shelf as noise can more easily enter the deep sound channel, travelling very efficiently for large distances [19] .

Maritime Spatial Planning should be managed with noise in mind, including acoustic buffer zones. However, up-to-date no noise-specific measures are however implemented in MSP. Spatial planning provisions specifically related to underwater noise are found only in the German plan which designates a temporary reservation area for harbour porpoises during reproductive periods (May-August) [20].

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.