Assessment of seafloor marine litter along the Montenegrin coast through Fishing for Litter initiatives

This report was commissioned by the Swedish Agency for Marine and Water management and written by analysts at the Swedish Institute for the Marine Environment (affiliated with the University of Gothenburg, Lund University, and Chalmers University of Technology). This report documents how marine plastic litter reaches even the most remote parts of the oceans with small island states, and how SIDS are especially vulnerable to its impact. The origin and composition of marine plastic litter and its impacts are described. Measures are discussed, both from state agencies and private corporations. Measures from existing RAPs on marine litter are reviewed and examples of private initiatives are mentioned. Also, the corresponding legal framework is given and side effects of marine litter measures on the Sustainable Development Goals of the UN are debated. THE VULNERABILITY OF SIDS SIDS are a set of island nations in the Caribbean Sea, the Pacific Ocean, the Atlantic, Indian Ocean, and the South China Sea. SIDS are exposed to disproportionate concentrations of plastic litter due to their location near the ocean gyres where marine litter accumulates and to often sub-performing waste management systems. ORIGINS AND COMPOSITION OF MARINE PLASTIC LITTER Because plastic make up most marine debris, the focus here is on plastic litter. Marine plastic litter washed ashore on SIDS originates from both distant countries overseas and the SIDS themselves. Buoyant plastic litter is globally distributed by ocean currents and is washed ashore on beach lines around the globe where it negatively impacts ecological and human systems. Plastics end up in the marine environment through leaks from the global value chains that run from the oil industry through various other industries to local retailers and consumers. A smaller but significant stream of plastic litter follows from the difficulties of many SIDS to establish and maintain efficient waste management systems. IMPACT OF PLASTIC LITTER ON ECOLOGICAL, SOCIAL, AND ECONOMIC VALUES Marine litter impacts the environment and organisms therein in various ways, including entanglement, ingestion, transfer of chemicals, or by otherwise altering habitats. The extent of the social and economic impact that plastic on countries is not currently well known. However, the dependence of SIDS on their natural resources through tourism and fisheries, make them economically vulnerable to plastic litter. MITIGATION AND REMEDIATION STRATEGIES For plastic that reaches SIDS, both remediation and mitigation, especially through waste management and recycling, become necessary. LEGAL AND POLITICAL FRAMEWORKS The legal framework for preventing and managing marine litter is present on all levels of governance. A declaration particularly relevant to marine litter on SIDS is the SAMOA Pathway, a declaration from the 3rd International Conference on Small Island Developing States in 2014 calling for measures to manage waste, including marine plastic litter. Multilateral agreements require party states to take actions, but these requirements are often generally formulated, and their achievements depend on the choices and participation of all parties. POLICY MEASURES PROPOSED BY REGIONAL ACTION PLANS There are 18 Regional Seas programmes under the United Nations Environmental Program for the protection of the marine environment. Some Regional Seas programmes have written strategies to guide their actions, the RAPs, i.e. a political agenda for marine litter management agreed on by member governments of the region. The contents of different RAPs show strong similarities. The analyses conducted here show that most measures suggested by RAPs are aimed at downstream processes, while fewer address the problem upstream. Additional measures are needed to solve such a global problem. VOLUNTARY AND COMMERCIAL INITIATIVES Marine litter requires an array of actions from local to global level, and is thus a matter of governance. Most measures suggested in RAPs and other work against marine litter involve government managers as well as businesses, NGOs, and voluntary initiatives. RECOMMENDATION: FUTURE COOPERATION Competence and enthusiasm for the issue on SIDS and elsewhere is growing, but more is needed. Solutions require international cooperation. Four recommendations for cooperation are highlighted here: 1. Prevent litter from entering the ocean and thus reaching SIDS: Support cooperation in regional and international agreements 2. Plastic material reaching SIDS should not be released into the environment: Technical cooperation and support for local waste management 3. If waste reaches the environment, collect it where appropriate: Support beach clean-up campaigns and other remediation measures 4. When waste has been collected, ensure that is has a value: Develop recycling markets and opportunities

Marine litter in submarine canyons of the Bay of Biscay

Although the seafloor is an important sink for marine litter, its less accessible environment makes seafloor litter the least studied component. Nevertheless, detailed monitoring of its composition and spatial distribution is urgently needed to develop appropriate mitigation strategies in areas exposed to multiple anthropogenic pressures, such as the Adriatic Sea. Commercial fisheries such as bottom trawls can serve as an opportunistic platform for collecting data on seafloor litter and help researchers in addressing the lack of data through Fishing for Litter initiatives. In this study, the crews of twelve trawlers from two Italian Adriatic ports collected seafloor litter as part of their Fishing for Litter initiatives. In addition to the classical scheme, the collected litter was sorted on board into different bags, and speed, duration and geographical coordinates of each haul were recorded to allow an assessment of both densities and spatial distribution. More than 600 kg of litter was removed from the seafloor by the fishers in approximately 1 month and characterised by the researchers on the docks. Most of the found items were made of synthetic polymers and related to packaging, fisheries and aquaculture activities. Abandoned, lost or discarded fishing gear and mussel nets were identified as of particular concern in the maritime compartment of Chioggia and Civitanova Marche, respectively. Three hotspots for marine litter were identified: near the Venice lagoon, in the centre of the northern basin and at greater depth in the central Adriatic. This study provides a detailed picture of the spatial distribution and composition of seafloor litter in the areas studied and highlights the importance of increased cooperation between fishermen and scientists to improve the identification of hotspots and sources while removing marine litter from the seafloor and raising awareness of the problem.

Distribution and composition of benthic marine litter on the shelf of Antalya in the eastern Mediterranean

This study presents a large-scale monitoring of marine litter performed in the joint Norwegian-Russian ecosystem monitoring surveys in the period from 2010 to 2016 and contribute to documentation of the extent of marine litter in the Barents Sea. The distribution and abundance of marine litter were calculated by recordings of bycatch from the pelagic trawling in upper 60m, from bottom trawling close to the sea floor, and floating marine debris at surface by visual observations. The study is comprehensive regarding coverage and number with registrations from 2265 pelagic trawls and 1860 bottom trawls, in addition to surface registration between the stations. Marine litter has been recorded from 301 pelagic and 624 of the bottom trawl catches. In total, 784 visual observations of floating marine debris were recorded during the period. Marine litter has been categorized according to volume or weight of the material types plastic, wood, metal, rubber, glass, paper, and textile. Marine litter is observed in the entire Barents Sea and distribution vary with material densities, ocean currents and depth. Plastic dominated number of observations with marine litter, as 72 % of surface observations, 94 % of pelagic trawls, and 86 % of bottom trawls contained plastic. Observations of wood constituted 19 % of surface observations, 1 % of pelagic trawls and 17 % of bottom trawls with marine litter. Materials from other categories such as metal, rubber, paper, textile, and glass were observed sporadically. Recordings of wood dominated surface observations (61.9±21.6% by volume) and on seafloor (59.4±35.0 % by weight), while plastic dominated marine litter observations in upper 60 m depth (86.4±16.5 % by weight) over these 7 years. Based on recordings and volume or area covered, mean levels of plastic in the upper 60 m of the Barents Sea were found to 0.011 mg m-3 (pelagic) and 2.9 kg km-2 at sea floor over the study period. Average levels of marine litter (all material types) at the sea floor were found to be 26 kg km-2.

A nationwide assessment of litter on China’s beaches using citizen science data

The habit of littering as well as illegal waste dumping into the river and the ocean is commonly found in various regions in Indonesia, including Alor island. Most of waste dumped on the land end up in the coastal through river flows and water run-off and at the and at the end is carried away to the ocean. The inappropriate existence of anthropogenic waste causes damage to marine and coastal ecosystems, for instance plastic ocean, while the ocean provides livelihood for most coastal people in Alor. In addition, dirty coastal areas due to trash littering and illegal waste dumping can be another issue in terms of marine tourism activity which is currently being promoted by the Alor Regency government. Therefore, further research is needed in order to support the making of waste management regulation as well as educational and awareness raising within people of Alor island. This research supported by citizen science of Plastic Free Ocean Network Alor identified the composition and concentration of marine litter in Alor Island using the line transect method developed by CSIRO. The result showed that the top three marine litter compositions in all locations during January-June 2019 were soft plastic, hard plastic and glass. The density of marine litter on Alor Island is categorized as high density as a whole. The location that contributed the highest marine litter density was Kadelang Beach.

Worldwide, the marine debris emissions have been provoking impacts in ecosystems, generating massive mortality of different species with commercial interest. In South America, we have a lack of studies to verify the marine debris composition in transitional environments such as adjacent regions of coastal jetties. These are hydraulic engineering constructions used to maintain the navigation channel access between the sea-estuarine interface and are also used by teleost fishes, crustaceans, and mollusks like artificial shelters (reefs), being excellent fishing grounds. Therefore, the present study was devoted to qualitatively evaluate the composition of marine debris in an internal jetty portion of a Laguna Estuarine System (LES) located in South America (Brazil). Six hundred freediving were conducted to collect marine debris in the study region. The in situ campaigns were performed in 2016 during all spring season (sand substrata) in four distinct zones with 26,400m2 each one covering almost all adjacent jetty extension, to evaluate possible spatial changes in the marine debris composition. All material obtained was identified, measured, weighed, and ordered in eight groups, with six groups being related to the fishing activity and two groups related to the tourism/community in the study region. So, it was possible to observe possible relations between the marine debris distribution to artisanal and recreational local fishing. After 600 freediving sampling efforts, 2142 marine debris items were obtained, totaling close to 100kg of solid waste removed from the inner portion of the coastal jetty. Notably, 1752units (50kg) of fishing leads were collected being this item the main marine debris residue found in the four sampled areas, corresponding to nearly 50% of the total weight of the collected waste. Ninety-eight percent of marine debris were derived from the local fishing activities, and just 2% were derived from tourism/community. Considering the total contribution related to fishing, 83% of the marine debris were composed by lead (sinkers) adopted by recreational and artisanal fishing. Notably, the catch activity in this region has a close influence over the marine debris composition. Reductions of marine debris emissions derived from the fishing activities have been a global challenge, once this problem is occurring in practically all marine and estuarine environments under the anthropic action. The presence of marine debris changes the local landscape and can provoke serious environmental problems, such as ghost fishing that affects a wide variability of marine mammals, birds, and fishes. Most of marine debris collected came from recreational and artisanal fishing, being the fishing leads the most prominent material, especially in sector 4. This fact is possibly related to the intense mullet fishing using cast nets, usual in this sample area. In the other sectors, there was a great predominance of grapnel fishing leads, widely adopted by recreational fishermen in open water environments. The "fingernails" present in these fishing leads ensure the sinking of the line for a specific location independently of possible flow oscillations of the tidal current and/or currents generated by winds. The massive quantity of fishing leads into the sectors is a dangerous fact. Notably, lead is a heavy, non-biodegradable, and extremely toxic metal that, due to the anthropogenic activities, has been increasing around the world. Future efforts in our study region should evaluate the seasonal marine debris composition to observe possible changes along the different seasons of the year. In this way, it would be possible to infer quantitatively the emission of marine debris derived from the fishing activity, assessing its impacts and enabling the adoption of environmental management strategies. This effort adopted a qualitative analysis, serving to show the current situation of this region that we now know to be vulnerable to the presence of marine debris derived from the fishing activity.

Spatio-temporal variations of litter on Qingdao tourist beaches in China

Large-scale monitoring of anthropogenic marine litter in the Barents Sea was carried out in 2012–2018. The marine litter composition was estimated by recording by-catch from pelagic and bottom trawling. Litter on the sea surface (floating litter) was also taken into account during visual observations. The contents of 949 pelagic and 1477 bottom trawls were analyzed. Marine litter was recorded in 256 pelagic and 571 bottom trawl catches and in 454 cases during visual observations. Litter was sorted into plastic, wood, metal, rubber, textiles, paper, and glass. The occurrence of plastic prevailed in all litter records. It covered 71% of marine litter observed on the surface, 97% in pelagic trawls, and 78% in bottom trawls. Fishery litter prevailed in plastic litter (about 65% of its weight). Wood was recorded in 19% of surface litter observations, 1% in pelagic trawls and 13% in bottom ones. Metal, rubber, paper, textiles, and glass were occasionally observed; however, their weight (except glass) could be very large. Thus, metal and wood prevailed by weight on the bottom (45 and 36.8%, respectively). Wood prevailed in pelagic layers, being 73% of the total litter weight. The volume of plastic and wood prevailed on the sea surface (50 and 47%, respectively). The average density of all types of litter on the sea bottom was about 7.9 kg/km2. Some significant differences in the litter composition were recorded between the southwestern and northeastern areas of the Barents Sea.

Marine litter (ML) is accidentally removed by fishing gear every day, a fact that is being capitalized in strategies known as Fishing for Litter (FFL). In the Mediterranean Sea, this removal effect plays a particularly important role due to its enclosed nature and the reportedly high values of benthic ML abundance. In 2018, ICATMAR, the Catalan Institute of Research for the Governance of the Sea, launched a continuous fisheries monitoring program along the Catalan coast (NW Mediterranean Sea), which includes the study of ML collected from bottom trawlers. The program consists of monthly samplings on board commercial vessels from the 9 main bottom trawl ports of the area and, since 2024, it is endorsed by the UN Ocean Decade. Understanding the importance of detecting the origin of ML to provide science-based advice in waste policy, this study investigated the potential source of the ML collected by the bottom trawl fleet.The present study analyzed data from 2018 to 2022. The ML collected was weighted and classified into six different categories including metal, plastic, rubber, textile, wood, and other waste. Benthic ML was present in 97 % of the hauls performed, and its composition varied along the coast. The overall mean density was 7.91 ± 0.96 kg km-2. The highest densities were found in highly urbanized areas, i.e., Barcelona metropolitan area, where some hauls reached 201.94 kg km-2. Plastic represents the 63.42% of the total ML density observed in the whole area, with a mean density of 5.35 ± 0.79 kg km-2, although in some hot spots, the mean ML density was as high as 158.07 kg km-2.Results showed that ML density was directly related to distance to river mouths, submarine outfalls, and highly populated areas. In addition, no correlation was found between ML and fishing effort, meaning that Fishing for Litter strategies can be useful sources of information, but they are not to be considered as a problem-solving strategy. The present study confirms that waste management policies must be implemented on-land, especially in highly anthropic areas with large populations.

Seafloor marine litter density and distribution in the Jordanian Gulf of Aqaba, northern Red Sea.

Effects of natural and anthropogenic processes in the distribution of marine litter in the deep Mediterranean Sea

Amount and distribution of benthic marine litter along Sardinian fishing grounds (CW Mediterranean Sea)

Three beaches on the Eastern Black Sea coast of Türkiye, with different usage purposes and urbanization, were evaluated regarding marine litter densities and categories in four seasons. 3573 marine litter items were collected, classified, and recorded. In an area of 3,000 m2, the highest amount of litter was counted in summer with a total of 1473 pieces of litter (Average: 0.491 ± 0.131 items/m2), and the lowest was counted in the spring months with 577 pieces of litter (Average: 0.192 ± 0.026 items/m2). Plastics (79 ± 0.9%) were the most predominant, and litter items mainly consisted of metal (7.2 ± 0.5%) and paper/cardboard (5.6 ± 0.6%.). Beach litter was also associated with fishing activities and tourism. It was observed that litter relatively increased during the fishing season in the region where fishing activities were intense. SIMPER analysis revealed that Çamburnu, located near a fishing port, exhibited a significantly different litter composition, with fishing gear being the most dominant category.