Marine debris is a management issue with ecological and recreational impacts for agencies, especially on remote beaches not accessible by road. This project was implemented to remove and document marine debris from five coastal National Park Service units in Alaska. Approximately 80 km of coastline were cleaned with over 10,000 kg of debris collected. Marine debris was found at all 28 beaches surveyed. Hard plastics were found on every beach and foam was found at every beach except one. Rope/netting was the next most commonly found category, present at 23 beaches. Overall, plastic contributed to 60% of the total weight of debris. Rope/netting (14.6%) was a greater proportion of the weight from all beaches than foam (13.3%). Non-ferrous metal contributed the smallest amount of debris by weight (1.7%). The work forms a reference condition dataset of debris surveyed in the Western Arctic and the Gulf of Alaska within one season.
The abundance and distribution of plastic debris in the marine environment show patterns of near- and offshore generation, migration toward and accumulation in the subtropical gyres, fragmentation, and redistribution globally. Ecological impacts in the subtropical gyres include invasive species transport and rampant ingestion and entanglement; yet plastics have also created substantial new habitat, resulting in population increases in some species. Though estimates of surface abundance and weight indicate over a quarter million tons and particle counts in the trillions, there is also a rapid removal of microplastics from the sea surface. Recent studies show widespread occurrence of these microplastics throughout the vertical column and in benthic and coastal sediments. It is likely that sedimentation is the ultimate fate for plastic lost at sea. Before microplastics sink, they likely cause significant impacts to marine food chains and ecosystems. In the open ocean, plastics are mingled with marine communities, making removal at sea prohibitive. This new understanding informs mitigation efforts to divert attention away from open-ocean cleanup. Similar to the way societies dealt with widely distributed particulate contamination in the air above cities, the “smog” of microplastics destined to pass through marine ecosystems before finally settling on the seafloor is best addressed with preventative measures.
This research aims to define for the first time levels and patterns of different litter groups (macro, meso and microplastics) in sediments from a marine area designed for the institution of a new marine protected area (Aeolian Archipelago, Italy). Microplastics resulted the principal group and found in all samples analyzed, with shape and colours variable between different sampling sites. MPs levels measured in this study are similar to values recorded in harbour sites and lower than reported in Adriatic Sea, while macroplastics levels are notably lower than in harbor sites. Sediment grain-size and island extent resulted not significant in determining levels and distribution of plastic debris among islands. In the future, following the establishment of the MPA in the study area, these basic data will be useful to check for potential protective effects on the levels and distribution of plastic debris.
Understanding plastic pollution from a systems perspective requires a way of conceptualizing sources, distribution and dynamics in the environment; identifying or quantifying impacts on wildlife, humans and other assets; and identifying and evaluating potential management responses. The uncertainties in our knowledge and the difficulty in resolving them satisfactorily can be challenging, given that we are confined to working with largely observational data because experiments at scale are difficult or impossible. To advance this area of research, we suggest applying a conceptual framework that allows us to break the components into smaller parts that can integrate uncertainty and connect variables of interest to outcomes of interest. We identify four specific questions inherent to a risk framework: the first three focus on risk analysis, and the fourth on risk management or mitigation. We present examples that are both data rich and data poor and discuss the value of integrating a systems perspective, connecting sources and drivers to dynamics and distribution to impacts and management responses. We also propose applying risk analysis to the plastics pollution issue as we acknowledge and embrace uncertainty, noting the precautionary principle and its application to risk management.
This report provides an update and further assessment of the sources, fate and effects of microplastics in the marine environment, carried out by Working Group 40 (WG40) of GESAMP (The Joint Group of Experts on Scientific Aspects of Marine Protection). It follows publication of the first assessment report in this series in April 2015 (GESAMP 2015). The issue of marine plastic litter was raised during the inaugural meeting of the United Nations Environment Assembly (UNEA) in June 2014. Delegates from 160 countries adopted Resolution 1/6 on ‘Marine plastic debris and microplastics’ (Annex I). The resolution welcomed the work being undertaken by GESAMP on microplastics and requested the Executive Director of UNEP to carry out a study on marine plastics and microplastics. This was to be based on a combination of existing and new studies, including WG40. This provided the motivation for GESAMP to revise the original terms of reference to reflect both the request from UNEP to contribute to the UNEA study, and the key recommendations from the WG40 2015 report.
Twenty-six beaches belonging to Atlántico department, Caribbean coast of Colombia, were surveyed to determine magnitudes, sources, and management of litter. Beach litter was observed along the entire coastline, and a total of 7,597 items weighing 412 kg were collected from all 26 beaches surveyed. The average abundance of litter found along the study area was 2.9 items m−1. Vegetation debris and plastic items dominated the samples respectively with 59% (Avg: 1.72 items m−1) and 27% (Avg: 0.82 items m−1). Other litter groups were polystyrene 3% (Avg: 0.1 items m−1), rubber 3% (Avg: 0.08 items m−1) and glass 2% (Avg: 0.04 items m−1). Metal, organic, processed wood, paper and biohazards items reached 5%, while textiles and miscellaneous represented less than 1%. Concerning buoyancy characteristics, the most represented litter category was persistent buoyant litter (with 91% of items), followed by short-term (6%) and non-buoyant litter (3%). The primary source of litter corresponds to litter transported by rivers, mainly the Magdalena River, together with human activities related to beach use (i.e.tourism). Litter produced poor scenic scores along the Atlántico department coastline and improvement can easily upgrade scenic beach quality scores. Results such as those given are necessary to identify, improve and conserve beaches standards together with the contribution that they make to the environmental, social and economic, well-being of local communities. Beach litter management along the study area (as well along the Caribbean coast of Colombia) must be based on strategies to reduce or eliminate litter sources. For that, it is necessary to consider beach types to define the intensity and periodicity of actions to be implemented.
Microplastic debris is a pervasive type of contaminant in marine ecosystems, being considered a major threat to marine biota. One of the problems of microplastics is that they can adsorb contaminants in extremely high concentrations. When released from the particle, these contaminants have the potential to cause toxic effects in the biota. So far, reports of toxic effects are mostly linked with the direct exposure of organisms through ingestion of contaminated microplastics. There is little information on the toxicity of leachates from microplastics to marine organisms. In this study, we conducted experiments to evaluate the toxicity of leachates from virgin and beached plastic pellets to embryo development of the brown mussel (Perna perna). We compared the efficiency of two test procedures, and evaluated the toxicity of beached pellets collected in a coastal marine protected area. We observed that mussel embryo is sensitive to leachate from both virgin and beached pellets. However, the toxicity of the leachate from beached pellets was much higher than that of virgin pellets. We suggest contaminants adsorbed onto the surface of beached pellets were responsible for the high toxicity of leachate from beached pellets, while the toxicity of leachate from virgin pellets was mainly due to plastic additives. Our results suggest microplastic debris may be harmful even if ingestion is not the only or main pathway of interaction of marine organisms with contaminated plastic debris.
In two sea voyages throughout the Mediterranean (2011 and 2013) that repeated the historical travels of Archduke Ludwig Salvator of Austria (1847–1915), 71 samples of floating plastic debris were obtained with a Manta trawl. Floating plastic was observed in all the sampled sites, with an average weight concentration of 579.3 g dw km−2(maximum value of 9298.2 g dw km−2) and an average particle concentration of 147,500 items km−2 (the maximum concentration was 1,164,403 items km−2). The plastic size distribution showed microplastics (<5 mm) in all the samples. The most abundant particles had a surface area of approximately 1 mm2 (the mesh size was 333 μm). The general estimate obtained was a total value of 1455 tons dw of floating plastic in the entire Mediterranean region, with various potential spatial accumulation areas.
From nano-plastics to large sunken vessels, marine debris presents a threat to humans and ecosystems worldwide. Fishermen's knowledge of the sources of, and risks posed by medium to large debris derived from fishing, aquaculture, and other marine industries provides important context for debris mitigation. Public participation geographic information systems (PPGIS) can address these risks by integrating subjective and objective spatial data on human and environmental impacts and risks. We integrated fishermen's perceptions and experiences with marine debris with spatial data using PPGIS. We developed a georeferenced database of fishermen's experiences with marine debris, collected during focus groups and at various other meetings in Southwest New Brunswick. This layer was used to integrate baseline data with subjective perceptions of the ecological, economic, and navigational risks associated with marine debris in the Bay of Fundy, Canada. We also documented the physical, technical, political, and regulatory challenges to marine debris mitigation. These challenges highlight the social and environmental processes that complicate any projects that attempt to develop uncontested spatial representations of marine debris. Finally, we discuss the potential of PPGIS to address these challenges by fostering communication, coordinating various marine activities, helping stakeholders set priorities for clean-up, and implementing collaborative clean-up projects.
Marine debris from ships has persisted and remains a concern despite international agreements such as MARPOL. We report on an analysis of beach litter based on a data set established by the Marine Conservation Society (MSC) Beachwatch weekends. Debris collected around the UK was divided into three main types of debris: (1) plastic, (2) fishing, and (3) fishing related plastic and rubber. Correspondence analysis (CA) was used to examine patterns in the occurrence of debris types on a total of 1023 beaches and debris attributable to fishing was identified on clusters of beaches mainly located on the coasts of Scotland and along the English Channel. General Linear model (GLM) identified fishing as the highest explanatory factor when testing for relationships between litter and proximity to fishing ports and grounds. The results add to the growing body of evidence that the fishing industry is largely responsible for marine debris.
Over the past 3–4 decades, per capita consumption of personal care products (PCPs) has steadily risen, resulting in increased discharge of the active and inactive ingredients present in these products into wastewater collection systems. PCPs comprise a long list of compounds employed in toothpaste, sunscreen, lotions, soaps, body washes, and insect repellants, among others. While comprehensive toxicological studies are not yet available, an increasing body of literature has shown that PCPs of all classes can impact aquatic wildlife, bacteria, and/or mammalian cells at low concentrations. Ongoing research efforts have identified PCPs in a variety of environmental compartments, including raw wastewater, wastewater effluent, surface water, wastewater solids, sediment, groundwater, and drinking water. Here, an aggregate analysis of over 5000 reported detections was conducted to better understand the distribution of environmentally-relevant PCP concentrations in, and between, these compartments. The distributions were used to identify whether aggregated environmentally-relevant concentration ranges intersected with available toxicity data. For raw wastewater, wastewater effluent, and surface water, a clear overlap was present between the 25th–75th percentiles and identified toxicity levels. This analysis suggests that improved wastewater treatment of antimicrobials, UV filters, and polycyclic musks is required to prevent negative impacts on aquatic species.
Anthropogenic debris in the world’s oceans and coastal environments is a pervasive global issue that has both direct and indirect impacts on avifauna. The number of bird species affected, the feeding ecologies associated with an increased risk of debris ingestion, and selectivity of ingested debris have yet to be investigated in most of Australia’s coastal and marine birds. With this study we aim to address the paucity of data regarding marine debris ingestion in Australian coastal and marine bird species. We investigated which Australian bird groups ingest marine debris, and whether debris-ingesting groups exhibit selectivity associated with their taxonomy, habitat or foraging methods. Here we present the largest multispecies study of anthropogenic debris ingestion in Australasian avifauna to date. We necropsied and investigated the gastrointestinal contents of 378 birds across 61 species, collected dead across eastern Australia. These species represented nine taxonomic orders, five habitat groups and six feeding strategies. Among investigated species, thirty percent had ingested debris, though ingestion did not occur uniformly within the orders of birds surveyed. Debris ingestion was found to occur in orders Procellariiformes, Suliformes, Charadriiformes and Pelecaniformes, across all surveyed habitats, and among birds that foraged by surface feeding, pursuit diving and search-by-sight. Procellariiformes, birds in pelagic habitats, and surface feeding marine birds ingested debris with the greatest frequency. Among birds which were found to ingest marine debris, we investigated debris selectivity and found that marine birds were selective with respect to both type and colour of debris. Selectivity for type and colour of debris significantly correlated with taxonomic order, habitat and foraging strategy. This study highlights the significant impact of feeding ecology on debris ingestion among Australia’s avifauna.
The plastic debris contamination, feeding ecology and habitat use of Cynoscion acoupa, an economically important species, were studied in relation to spatial, seasonal and ontogenetic aspects in a tropical estuary. The human impact on the environment was evident in the studied species, reflecting the high contamination of the diet of these fish with plastic debris. Plastic debris is frequently ingested by C. acoupa, regardless of season, area or ontogenetic phase. However, a higher frequency and amount of ingestion suggests that this contaminant might also be acquired through direct consumption and biotransference (from contaminated prey). The ontogenetic phases of C. acoupa utilized different estuarine reaches during seasonal fluctuations. This behaviour was strongly influenced by environmental variables, particularly salinity. During all seasons, juveniles used the upper estuary as shelter to avoid marine predators. However, in the early rainy season, the upper estuary was significantly important as a nursery for this species. The sub-adults used the upper estuary as a feeding ground during the year and migrated to the middle estuary during the late rainy season to avoid osmoregulatory stress. Adults were observed only in the coastal waters of the lower estuary. The trophic guild changed during the ontogeny of C. acoupa, and juveniles primarily fed on plastic debris (FO = 64%), amphipoda (FO = 34%), mysidacea (FO = 17%) and Cathorops spixii (FO = 15%). Sub-adults preferred plastic debris (FO = 50%) and C. spixii (FO = 30%). Both juveniles and sub-adults were classified as opportunistic. Adults were piscivorous, ingesting plastic debris (FO = 100%), C. spixii (FO = 18%), Achirus lineatus(FO = 15%), Stellifer stellifer (FO = 15%) and penaeid shrimp (FO = 15%).
Marine debris produces a wide variety of environmental, economic, safety, health, and cultural impacts and is rapidly achieving recognition as a key anthropogenic threat to global oceanic ecosystems. A central theme of research on habitat degradation via marine debris is determining the impact of specific types of debris (abandoned or derelict fishing gear and plastics in particular) on sensitive habitats. This report explores the impacts of marine debris as they affect coastal and ocean habitats, including sandy beaches, salt marshes, mangrove forests, coral reefs and hard bottom, seagrass, benthic sediments, and oyster reefs. Other important habitats—such as areas with kelp and macroalgae, rocky intertidal areas, and freshwater systems such as the Great Lakes region—are lacking research on the effects of marine debris and are in need of more attention regarding habitat impacts.
It is important to understand the nature and extent of the impacts caused by marine debris on marine habitats, which can directly affect many other parts of the ecosystem. Learning more about this problem enables us to better address it in the future.
This report explains the information sources and analysis underlying Eunomia’s marine plastics infographic, Where do they come from? Where do they go?
Understanding the movement of debris allows us to have a better grasp on how it might distribute and accumulate within our ocean and on our shores.This report reviews the scientific literature that exists on the subject and outlines the methods that are available to gain this sort of insight.
The following overview presents some of the numerical modeling techniques that have been applied to simulate the transport of marine debris. The primary approach to modeling the transport of drifting objects, with marine debris being one application, typically has involved the use of particle tracking models (PTMs) to estimate or simulate the movement of ‘particles’ over time. This movement depends on transport (advection) by ocean surface currents, and some PTMs may incorporate additional factors such as movement resulting from the proportion of buoyant objects floating high in the water and exposed to the wind (windage), or a random motion component (turbulent diffusion).
Coastal visits not only provide psychological benefits but can also contribute to the accumulation of rubbish. Volunteer beach cleans help address this issue, but may only have limited, local impact. Consequently, it is important to study any broader benefits associated with beach cleans. This article examines the well-being and educational value of beach cleans, as well as their impacts on individuals’ behavioral intentions. We conducted an experimental study that allocated students (n = 90) to a beach cleaning, rock pooling, or walking activity. All three coastal activities were associated with positive mood and pro-environmental intentions. Beach cleaning and rock pooling were associated with higher marine awareness. The unique impacts of beach cleaning were that they were rated as most meaningful but linked to lower restorativeness ratings of the environment compared with the other activities. This research highlights the interplay between environment and activities, raising questions for future research on the complexities of person-environment interactions.
The Great Barrier Reef (GBR) is an iconic coral reef system extending over 2000 km along the north-east coast of Australia. Global recognition of its Outstanding Universal Value resulted in the listing of the 348 000 km2 GBR World Heritage Area (WHA) by UNESCO in 1981. Despite various levels of national and international protection, the condition of GBR ecosystems has deteriorated over the past decades, with land-based pollution from the adjacent catchments being a major and ongoing cause for this decline. To reduce land-based pollution, the Australian and Queensland Governments have implemented a range of policy initiatives since 2003. Here, we evaluate the effectiveness of existing initiatives to reduce discharge of land-based pollutants into the waters of the GBR. We conclude that recent efforts in the GBR catchments to reduce land-based pollution are unlikely to be sufficient to protect the GBR ecosystems from declining water quality within the aspired time frames. To support management decisions for desired ecological outcomes for the GBR WHA, we identify potential improvements to current policies and incentives, as well as potential changes to current agricultural land use, based on overseas experiences and Australia's unique potential. The experience in the GBR may provide useful guidance for the management of other marine ecosystems, as reducing land-based pollution by better managing agricultural sources is a challenge for coastal communities around the world.
Marine litter is a growing environmental concern. With the rapid increase in global plastics production and the resulting large volume of litter that enters the marine environment, determining the consequences of this debris on marine fauna and ocean health has now become a critical environmental priority, particularly for threatened and endangered species. However, there are limited data about the impacts of debris on marine species from which to draw conclusions about the population consequences of anthropogenic debris. To address this knowledge gap, information was elicited from experts on the ecological threat (both severity and specificity) of entanglement, ingestion and chemical contamination for three major marine taxa: seabirds, sea turtles and marine mammals. The threat assessment focused on the most common types of litter that are found along the world's coastlines, based on data gathered during three decades of international coastal clean-up efforts. Fishing related gear, balloons and plastic bags were estimated to pose the greatest entanglement risk to marine fauna. In contrast, experts identified a broader suite of items of concern for ingestion, with plastic bags and plastic utensils ranked as the greatest threats. Entanglement and ingestion affected a similar range of taxa, although entanglement was rated as slightly worse because it is more likely to be lethal. Contamination was scored the lowest in terms of impact, affecting a smaller portion of the taxa and being rated as having solely non-lethal impacts. This work points towards a number of opportunities both for policy-based and consumer-driven changes in plastics use that could have demonstrable affects for a range of ecologically important taxa that serve as indicators of marine ecosystem health.
The Mediterranean Sea is one of the most polluted seas worldwide, especially with regard to plastics. The presence of this emerging man made contaminant in marine environments precludes large effects and interactions with species exposed to massive litter quantities. In this review, available data of floating and seafloor litter around Mediterranean sub-basins are reported. A review of scientific literature on the interaction of plastic with marine biota resulted in the identification of 134 species, several taxa and feeding strategies affected from 1986 to 2014. Data from 17,334 individuals showed different levels of ingestion and effects on catalogued IUCN species (marine mammals and sea turtles) in addition to several pelagic fish and elasmobranchs. Biodiversity is certainly under threat, and knowledge of the extent of taxa affected is of concern considering the increasing plastic loads in the Mediterranean Sea and worldwide.