Interannual variability in marine debris accumulation on Hawaiian shores: The role of North Pacific Ocean basin-scale dynamics

Community-based marine debris removal efforts on the Hawaiian Islands of Kaua'i and Hawai'i, spanning 2013-2022, provided large datasets and documented remarkable variations in annual amounts of debris, mainly from abandoned, lost and derelict fishing gear. To test the hypothesis that the influx of marine debris on Hawaiian shores is determined by the proximity of the North Pacific garbage patch, whose pattern changes under the control of large-scale ocean dynamics, we compared these observational data with the output of an oceanographic drift model. The high correlations between the total mass of debris collected and the model, ranging between r = 0.81 and r = 0.84, validate the attribution of the strong interannual signal to significant migrations of the garbage patch reproduced in the model experiments. Synchronous variations in marine debris fluxes on the two islands, separated by >500 km, confirm the large scale of the interannual changes in the North Pacific marine debris system.

Simulating drifting fish aggregating device trajectories to identify potential interactions with endangered sea turtles

Purse-seine fishers using drifting fish aggregating devices (dFADs), mainly built with bamboo, plastic buoys, and plastic netting, to aggregate and catch tropical tuna, deploy 46,000-65,000 dFADs per year in the Pacific Ocean. Some of the major concerns associated with this widespread fishing device are potential entanglement of sea turtles and other marine fauna in dFAD netting; marine debris and pollution; and potential ecological damage via stranding on coral reefs, beaches, and other essential habitats for marine fauna. To assess and quantify the potential connectivity (number of dFADs deployed in an area and arriving in another area) between dFAD deployment areas and important oceanic or coastal habitat of critically endangered leatherback (Dermochelys coriacea) and hawksbill (Eretmochelys imbricata) sea turtles in the Pacific Ocean, we conducted passive-drift Lagrangian experiments with simulated dFAD drift profiles and compared them with known important sea turtle areas. Up to 60% of dFADs from equatorial areas were arriving in essential sea turtle habitats. Connectivity was less when only areas where dFADs are currently deployed were used. Our simulations identified potential regions of dFAD interactions with migration and feeding habitats of the east Pacific leatherback turtle in the tropical southeastern Pacific Ocean; coastal habitats of leatherback and hawksbill in the western Pacific (e.g., archipelagic zones of Indonesia, Papua New Guinea, and Solomon Islands); and foraging habitat of leatherback in a large equatorial area south of Hawaii. Additional research is needed to estimate entanglements of sea turtles with dFADs at sea and to quantify the likely changes in connectivity and distribution of dFADs under new management measures, such as use of alternative nonentangling dFAD designs that biodegrade, or changes in deployment strategies, such as shifting locations.

Ghost fishing efficiency in swimming crab (Portunus trituberculatus) pot fishery

Abandoned, lost, or otherwise discarded fishing gear (ALDFG) is a global challenge that negatively affects marine environment through plastic pollution and continued capture of marine animals, so-called "ghost fishing". In different pot fisheries, ghost fishing related to ALDFG is of concern, including pot fishery targeting swimming crab (Portunus trituberculatus). This study quantified the ghost fishing efficiency by comparing it to the catch efficiency of actively fished pots of the commercial fishery. The results showed that the ghost fishing affects both target and bycatch species. On average, the ghost fishing pots captured 12.53 % (confidence intervals: 10.45 %-15.00 %) undersized crab and 15.70 % (confidence intervals: 12.08 %-20.74 %) legal-sized crab compared to the actively fished pots. Few individuals of several bycatch species were also captured by ghost fishing pots. The results of this study emphasized the need to develop new management strategies for reducing marine pollution by ALDFG and associated negative effects in this pot fishery.

Retrieval operations of derelict fishing gears give insight on the impact on marine life

Abandoned, lost and discarded fishing gear (ALDFG), significantly impacts marine ecosystems and biodiversity by incidental capture known as ghost fishing. Such impacts were quantified during the Norwegian Directorate of Fisheries' annual ALDFG cleanup operation in September 2023 by examining the characteristics of retrieved ALDFG and recording the taxonomically sorted catch abundance and biomass. A total of 307 specimens equaling 382 kg of biomass were caught in the recovered gillnets and king crab pots. Gillnets exhibited a 27.3 % greater catch abundance and 50.3 % higher biomass per ALDFG unit mass compared to king crab pots. Margalef, Menhinick, Simpson, Shannon, and Pielou diversity indices showed a more pronounced impact on species richness and biodiversity associated with recovered gillnets. This study introduces an approach to assess the impact of ghost fishing on ecosystems and biodiversity through ALDFG retrieval operations, instrumental in developing estimates of the total ghost fishing capture by ALDFG.

Multi-stakeholder perspective to generate evidence and strategies for sustainable management of ropes from the fishing sector of Norway

Marine plastic pollution is a growing stressor affecting both marine and terrestrial life. Plastic polymers are widespread in oceans, including sparsely populated Nordic countries. Norway, a fishing-dominant region, faces substantial plastic pollution from fishing ropes, which often end up incinerated, landfilled, or lost in the ocean, contributing to the ghost fishing problem. This research employs a static material flow analysis (MFA) to assess plastic mass flows and the recyclability of 15 rope types used in Norway's commercial fishing sector. Findings reveal that approximately 383 tons of ropes are lost annually in Norwegian waters, endangering fish species. Furthermore, only one-third of the rope types can be efficiently recycled using available recycling technologies, highlighting the need for circularity. The MFA and inventory-based ranking approach shows significant potential as a holistic decision support tool for industry and policymakers in exercising sustainable and circular management for ropes.

Predicting the distribution and abundance of abandoned, lost or discarded fishing gear (ALDFG) in the deep sea of the Azores (North Atlantic)

Abandoned, lost, or discarded fishing gear (ALDFG), represents a significant percentage of the global plastic pollution, currently considered one of the major sources from sea-based activities. However, there is still limited understanding of the quantities of ALDFG present on the seafloor and their impacts. In this study, data on the presence of ALDFG was obtained from a large archive of seafloor video footage (351 dives) collected by different imaging platforms in the Azores region over 15 years (2006-2020). Most ALDFG items observed in the images relate to the local bottom longline fishery operating in the region, and include longlines but also anchors, weights, cables and buoys. A generalized additive mixed model (GAMM) was used to predict the distribution and abundance of ALDFG over the seafloor within the limits of the Azores Exclusive Economic Zone (EEZ) using a suite of environmental and anthropogenic variables. We estimated an average of 113 ± 310 items km-2 (597 ± 756 per km-2 above 1000 m depth), which could imply that over 20 million ALDFG items are present on the deep seafloor of the Azores EEZ. The resulting model identified potential hotspots of ALDFG along the seabed, some of them located over sensitive benthic habitats, such as specific seamounts. In addition, the interactions between ALDFG and benthic organisms were also analysed. Numerous entanglements were observed with several species of large anthozoans and sponges. The use of predictive distribution modelling for ALDFG should be regarded as a useful tool to support ecosystem-based management, which can provide indirect information about fishing pressure and allow the identification of potential high-risk areas. Additional knowledge about the sources, amounts, fates and impacts of ALDFG will be key to address the global issue of plastic pollution and the effects of fishing on marine ecosystems.

The hotspots of entanglement for pinnipeds of the world

Pinnipeds represent one of the most vulnerable marine groups severely affected by entanglements. However, the lack of standardized data collection poses a challenge when comparing the impacts of fishing gear across various geographic regions. In this study, we employed Generalized Additive Models to predict entanglement incidents stemming from fishing-related activities for 13 pinniped species across the last four decades (1976-2017). The models incorporated reported entanglement numbers, fishing effort covariates based on different gear types, and floating plastic debris distribution for each species. Through this approach, we generated global hotspot maps that pinpoint regions of heightened vulnerability where pinnipeds are susceptible to entanglement in lost gear. The best-performing model highlighted both species characteristics and the presence of floating plastic debris as pivotal factors in predicting pinniped entanglements. Our analysis revealed entanglement hotspots in the North Pacific and Southeastern Australia. This demonstrates the efficacy of our methodology in identifying high-priority geographic areas.

Comparison of physical properties and fishing performance between biodegradable PLA and conventional PA trammel nets in grey mullet (Mugil cephalus) and red-lip mullet (Liza haematocheila) fishery

Marine plastic pollution and continuous capture of marine animals, so-called "ghost fishing", by abandoned, lost, or otherwise discarded fishing gear (ALDFG) are global concerns. This study investigated whether biodegradable polylactic acid (PLA) monofilaments can be used to replace conventionally used non-biodegradable polyamide (PA) in trammel net fishery for limiting ALDFG associated effects. It evaluated the physical properties of PLA and PA monofilaments and compared fishing performance of PLA and PA trammel nets in a commercial mullet fishery in the Yellow Sea, China. Although PA monofilament exhibited superior physical properties, no significant differences in catch efficiency between PA and PLA trammel nets were observed. Fish of both species were mainly captured by pocketing which can further explain observed similar catch efficiency. These initial results suggest a potential for applying biodegradable materials in trammel net fisheries. Therefore, further long-term testing is encouraged to investigate whether this promising performance is persistent over long-term.

Modelled and observed plastic pollution on remote Scottish beaches: The importance of local marine sources

Beach-cleans conducted on the west coast of Scotland investigated the distribution of land- and marine-sourced litter and compared these with a particle tracking model representing the presumed principal land-based source. Modelled particles dispersed widely, even reaching the remote northwest coast, with 'hotspots' and 'coldspots' on windward and leeward coasts respectively. In beach sampling, however, land-sourced litter represented only 19% of items by count and 8% by weight, while marine-sourced litter represented 46% by count and 62% by weight. The source of the remainder could not be identified. Windward coasts had an average count of 1859 litter items per 100 m, and weight of 14,862 g per 100 m. Leeward coasts had an average count of 32 litter items per 100 m and weight of 738 g per 100 m. Field observations and model predictions were consistent in many respects for land-sourced litter, however marine-sourced litter is dominant on many coastlines.

Implementing the voluntary guidelines for the marking of fishing gear in eastern Caribbean small-scale fisheries: An assessment of gear marking provisions

Managing abandoned, lost and otherwise discarded fishing gear (ALDFG) is a critical challenge that can be aided by the establishment of strong provisions for the marking of gear. This study presents an analysis of implementation of the VGMFG in Eastern Caribbean states. It provides a socio-legal review of this issues and an analysis of compliance and implementation gaps. Empirical data was gathered through interviews with 56 fishers in 2 jurisdictions as well as 6 national and regional fisheries management experts. Antigua and Barbuda's Fisheries Regulations provided the strongest support to implementation of the VGMFG, while neither Dominica nor Grenada had weak regulatory support for gear marking. Both fishers and fisheries managers in the region confirmed compliance and implementation gaps in the establishment of gear marking schemes, while regional fisheries experts highlighted the limited human, financial and infrastructural capacity of departments to effectively implement such schemes along with other ALDFG management measures.

Monitoring the composition, sources and spatial distribution of seafloor litter in the Adriatic Sea (Mediterranean Sea) through Fishing for Litter initiatives

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.

Interactions between marine megafauna and plastic pollution in Southeast Asia

Southeast (SE) Asia is a highly biodiverse region, yet it is also estimated to cumulatively contribute a third of the total global marine plastic pollution. This threat is known to have adverse impacts on marine megafauna, however, understanding of its impacts has recently been highlighted as a priority for research in the region. To address this knowledge gap, a structured literature review was conducted for species of cartilaginous fishes, marine mammals, marine reptiles, and seabirds present in SE Asia, collating cases on a global scale to allow for comparison, coupled with a regional expert elicitation to gather additional published and grey literature cases which would have been omitted during the structured literature review. Of the 380 marine megafauna species present in SE Asia, but also studied elsewhere, we found that 9.1 % and 4.5 % of all publications documenting plastic entanglement (n = 55) and ingestion (n = 291) were conducted in SE Asian countries. At the species level, published cases of entanglement from SE Asian countries were available for 10 % or less of species within each taxonomic group. Additionally, published ingestion cases were available primarily for marine mammals and were lacking entirely for seabirds in the region. The regional expert elicitation led to entanglement and ingestion cases from SE Asian countries being documented in 10 and 15 additional species respectively, highlighting the utility of a broader approach to data synthesis. While the scale of the plastic pollution in SE Asia is of particular concern for marine ecosystems, knowledge of its interactions and impacts on marine megafauna lags behind other areas of the world, even after the inclusion of a regional expert elicitation. Additional funding to help collate baseline data are critically needed to inform policy and solutions towards limiting the interactions of marine megafauna and plastic pollution in SE Asia.

Material flow analysis of commercial fishing gears in Taiwan

Marine debris is an international environmental issue, and the growing amount of abandoned, lost, or otherwise discarded fishing gear (ALDFG) is a particular concern. Despite Taiwan's substantial fishing industry, there is a lack of comprehensive understanding of fishing gear. This work conducted a static material flow analysis to estimate the flows and the stocks of fishing gear in Taiwan in 2020, based on government statistics and interviews with fishing gears producing companies, fishermen, and recycling companies. Our findings reveal that the inflow, outflow, and stock of the fishing gears are 8,846 t/a, 4,271 t/a, and 4,575 t/a, respectively. Only 36 % of end-of-life fishing gear is recycled, while the rest is incinerated or landfilled. Additionally, the stock comprises 27 % in use, 23 % in ports, and 50 % entering the ocean. These results underscore the need to increase recycling capacity, prevent loss in oceans, and promote repairs to extend the lifespan of fishing gear.

Material studies for the recycling of abandoned, lost or otherwise discarded fishing gear (ALDFG)

This study investigates the feasibility of material recycling for retrieved gillnets from the Baltic Sea collected during a campaign of the World Wildlife Fund (WWF) Germany. Fragments from the material were analysed by Fourier transform infrared (FTIR) spectroscopy revealing polyamide 6 (PA6), polypropylene (PP) and polyethylene terephthalate (PET) in net material, swim lines and sink lines, respectively. A visual examination by microscope found large quantities of minerals attached to the surface of the material as well as in knots and loops of the polymer structure. Ash tests showed that a pre-treatment of the material including sorting, shredding, density separation and washing allows to reduce the mineral content from more than 45% of the total to 1.1%. However, for a separation by density, it is important that the entangled fibres can move freely. This is a major challenge for a primary or secondary mechanical recycling because a substantial fibre length reduction is required for the small polymer fibres down to a diameter of 20 µm. Another challenge for all kinds of recycling is the presence of lead lines in gillnets. Automated technology for removing these does not exist until now. A manual removal is indispensable to limit the level of contamination. Due to the complex pre-treatment and the elevated heavy metal concentrations also a tertiary or feedstock recycling seems not to be a possible pathway for retrieved gillnets. Yet, other options such as a primary recycling in concrete or bitumen additives or quaternary recycling via incineration may be conceivable alternatives. But there are also some arguments against these options. Better product design must be the goal to prevent plastic pollution and establish a functioning circular economy. In this context, the heavy metal contamination by abandoned, lost or otherwise discarded fishing gear (ALDFG) must be stopped.

Abandoned, lost and discarded fishing gear 'ghost nets' are increasing through time in Northern Australia

The remote Gulf of Carpentaria (GoC) represents 10% of Australia's coastline. This large, shallow sea supports high-value fishing activities and habitat for threatened species, and is a sink for abandoned, lost and discarded fishing gear (ALDFG) 'ghost nets', most originating from fishing activities outside of Australia's Exclusive Economic Zone. With growing concerns about the plastic waste along the world's coastlines, we retrospectively analyzed ghost net sighting information from four aerial surveys across 15 years, to investigate whether densities of ghost nets are changing through time or in space. We found an increase in ghost nets, despite more than a decade of illegal fishing countermeasure and clean-up efforts in the broader region. This demonstrates that the input of ALDFG into the system currently overwhelms the substantial net removal activities. We make recommendations for improving monitoring and consider the underlying drivers of nets being lost to improve ghost gear management on land and at sea.

Digital media reveal negative impacts of ghost nets on Brazilian marine biodiversity

Abandoned, lost, or otherwise discarded fishing gear (ALDFG) is responsible for the entanglement of several marine species. Based on a search of digital media (i.e., Google and YouTube^BR), we assessed the negative impacts of ghost nets-a type of ALDFG-on Brazilian marine biodiversity. We found that ghost nets negatively affected crustaceans, fishes, reptiles, birds, and mammals in different parts of the Brazilian coast. Our reports include marine megafauna, such as the Bryde's whale and Guiana dolphin. In addition, we found that ghost nets impacted seven threatened species and had negative effects on animals within marine protected areas. Here, we provide an update on the negative impacts of ghost nets on Brazilian marine biota, but the real situation remains underestimated and somewhat obscure.

Fishing activities and viewpoints on fishing gear marking of gillnet fishers in small-scale and industrial fishery in the Gulf of Thailand

Gillnets can cause impacts on marine ecosystems when they become abandoned, lost or otherwise discarded fishing gear (ALDFG). Fishing gear marking is a tool to address ALDFG and its impacts. This study aims to compare the characteristics and fishing activities of fishers in small-scale fishery (SSF) and industrial fishery (IDF) as well as their viewpoints on fishing gear marking practice. Data were collected during July-November 2020 from 95 fishers in five coastal provinces of Thailand. Most fishers used crab gillnets; besides, fishing capability and intensity of fishers in IDF were higher than in SSF. Awareness of fishing gear marking practice of fishers in IDF was higher than in SSF, but acceptance was not different. Preferred material was fabric for fishers in SSF and plastic for fishers in IDF. Most fishers anticipated government as producer. Moreover, further studies are needed to develop suitable materials, installation and cost for fishing gear marking.

Fate of lost fishing gears: Experimental evidence of biofouling colonization patterns from the northwestern Mediterranean Sea

ALDFGs (abandoned, lost or otherwise discharged fishing gears) represent a major pollutant in the world's oceans, including the Mediterranean Sea, but very little is known about their long-term fate in the underwater environment. Here we investigate the destiny of ALDFGs in a coralligenous benthic community by studying the biofouling growing on them at 30 m depth over a three-year period. Results indicate that ALDFGs are quickly covered by biofouling, reaching maximum values of cover in one year. At this depth, the biofouling community results highly influenced by light-dependent seasonal cycles and a general four-steps colonization scheme is tentatively depicted: i) biofouling community is initially dominated by fast-growing organisms, with algae and hydrozoans settling after two weeks; ii) small-sized carbonatic organisms (e.g. bryozoans) appear after two months; iii) the same organisms (including coralline algae) become abundant after five to eight months; iv) conspicuous carbonatic skeletons (serpulids, bivalves and bryozoans) occur after one year increasing in complexity in the following months. The biofouling settled on ALDFGs, as well as growth rates of large carbonatic species, could provide useful information to estimate the age of lost lines and nets in retrieved material and in situ photo footage complementing the overview of the fishing impact in this specific environment. Finally, no signs of nylon degradation are reported, suggesting that the prevailing physical conditions and the biofouling cover extent could alter microplastics release from nylon ALDFGs.

Multi-criteria decision analysis (MCDA) method for assessing the sustainability of end-of-life alternatives for waste plastics: A case study of Norway

Plastic, and its pollution of marine ecosystems, has emerged as a global concern. Among the several other sources, plastics from abandoned, lost, or discarded fishing gears (ALDFG), and ropes are considered the most dangerous for marine wildlife. In EU states, the management ALDFG is prioritized through a dedicated action plan owing to the hazardous nature of ALDFG and the increase in commercial fishing activity in EU waters. The action plan demands to close the loop of plastics from fishing to ensure sustainable resource management using strategies of the circular economy (CE). Commercial fishing is a crucial sector in Norway, generating 4000 tons of waste plastic annually from fishing gears and ropes. While recycling, landfilling, and incineration are the standard end-of-life management options, the recycling industry in the region is immature. The lack of recycling capacity and inadequate infrastructure results in exporting most of the recyclable fraction out of Norway for further processing. Although within the framework of CE, the transboundary export of waste for recycling misses the opportunity to create value out of waste within the region. Therefore, in the pursuit of CE strategies, it is essential to ensure regional sustainability. In this study, we assess the environmental, economic, and social impacts of landfilling, incinerating, and recycling of waste fishing gears in Norway. To represent the current state, we include two existing recycling scenarios for the assessment, namely, recycling (inland) and recycling (export). Based on qualitative and quantitative data from relevant stakeholders, we adapted multi-criteria decision analysis (MCDA) to rank the end-of-life (EOL) alternatives through their ability to sustainably manage 4000 tons of waste plastics from fishing gears in Norway. The ranking and insights from stakeholder interaction were used to ascertain potential barriers in realizing principles of CE and to further recognize opportunities for establishing circular business models in the region.

The impact of marine litter from fish aggregation devices on vulnerable marine benthic habitats of the central Mediterranean Sea

The aim of this research was to assess marine litter abundance and its effects on the benthic fauna in an area of the central Mediterranean Sea exploited by fisheries using fish aggregating devices (FAD). The study was carried out by means of a remotely-operated vehicle (ROV). Derelict fishing gear, mainly FAD ropes, represented the main source of marine debris, contributing 96.2% to the overall litter. About 47% of debris items (mostly FAD ropes) entangled colonies of the protected black coral Leiopathes glaberrima. The results of this research will assist in the monitoring of "impact/harm" to the coral and other benthic communities, as recommended by the Marine Strategy Framework Directive and by the Integrated Monitoring and Assessment Programme. Preventive and mitigation measures (i.e., biodegradable fishing gear, onboard technology to locate and retrieve gear, reception and/or payment for old/retrieved gear, and introduction of no-take zones) to reduce the problem are discussed.

Assessment and distribution of seafloor litter on the deep Ligurian continental shelf and shelf break (NW Mediterranean Sea)

Litter has become a common component of marine ecosystems, and its assessment and monitoring are now of primary interest. Here, we characterized seafloor litter in the mesophotic depth range of the Ligurian Sea, one of the most urbanized basins of the Mediterranean Sea. Eighty sites (30-220 m depth) were investigated by by means of ROV video transects. Data regarding environmental parameters and anthropic pressures were used to explain the distribution of human-derived objects. Litter resulted widely distributed in all the investigated areas, with maximum densities of 7900 items ha^-1. It was mainly represented by abandoned fishing gears, with highest abundances found on the deep coastal rocky shoals exploited by artisanal and recreational fishermen. Urban litter, primarily represented by plastics, was generally higher close to shore, especially near river mouths and large harbors. Litter densities reported here are among the highest ever recorded in Europe, denoting the urgency for specific actions to prevent further spreading.

Are FADs a significant source of marine litter? Assessment of released debris and mitigation strategy in the Mediterranean sea

A poorly known form of marine litter known as Abandoned, Lost or otherwise Discarded Fishing (ALDFG) derives from fishing activities using FADs (Fish Aggregating Devices). In the Mediterranean Sea, this activity is widespread in southern Italy, Tunisia, Malta and Majorca (Spain). The way of constructing FADs, from a functional point of view, is very similar throughout the Mediterranean and consists mainly of the use of different materials for the floats and for the cables and blocks for anchoring. Every year, for at least 30 years, about 60,000 FADs have been placed at sea and in most cases are not recovered. In this study, through analysis of the scientific and grey literature, a historical reconstruction of the use of FADs in the Mediterranean Sea was made, including their spatial distribution, the number of objects and the materials used to build the devices. It has been estimated that approximately 1.6 million FADs were abandoned in the Mediterranean Sea between 1961 and 2017. The largest fishing areas are off Malta (34,465 km²) and Tunisia (23,033 km²). The greatest numbers of abandoned plastic sheets (452,742) and concrete blocks (905,483) were estimated to be around Tunisia, while the greatest amount, in terms of length, of polyethylene cable (399,423 km) was estimated to be around Sicily. About 30% of FADs used all over the world are used in the Mediterranean and are only of the anchored type (corresponding to about 90% of those anchored used worldwide). The legislation on the use of Mediterranean FADs is still poor and does not address environmental issues. An analysis of the possible environmental impacts of the FAD litter was made. Overall, reducing the number of FADs and introducing new types of FADs equipped with specific technological systems appear to be the most suitable strategies to mitigate the impact of FADs on the environment and resources, as well as measures and incentives to involve fishermen in their better management.

Pinniped entanglement in oceanic plastic pollution: A global review

Oceanic plastic pollution is a growing worldwide environmental concern, endangering numerous marine species. Pinnipeds are particularly susceptible to entanglement, especially in abandoned, lost or discarded fishing gear and packaging straps. We searched three international databases to compile a comprehensive review of all reported pinniped entanglements over the last 40 years, with the aim to identify areas of concern and foci for mitigation. The majority of published records of entanglement emanate from North America and Oceania and are focused on a few populous species (notably, Zalophus californianus and Arctocephalus gazella). Reporting bias, skewed research effort and incomplete understanding of plastic pollution and pinniped abundance overlap, combine to cloud our understanding of the entanglement problem. Broader geographical effort in entanglement data collection, reporting of such data, and improved quantification of the proportions of populations, sexes and ages that are most susceptible, will aid our efforts to pinpoint priority mitigation measures.

Marine litter from fishery activities in the Western Mediterranean sea: The impact of entanglement on marine animal forests

The anthropogenic marine debris, especially abandoned, lost or otherwise discarded Fishing Gear (ALDFG), represents a rising concern, because of its potential harmful impact on the marine animal forests. We carried out 13 km of video recordings, by means of a remotely operated vehicle, from 10 to 210 m depth, in an anthropised area of the Tyrrhenian Sea (Mediterranean Sea). This site, for its high ecological importance and biodiversity value, has been identified for the establishment of a new marine protected area (MPA). The aim of this paper was to assess marine litter abundance and its effects on the benthic fauna. The debris density, in the study area, ranged from 0.24 to 8.01 items/100 m², with an average of 3.49 (±0.59) items/100 m². The derelict fishing gear, mainly fishing lines, were the main source of marine debris, contributing 77.9% to the overall litter. The impacts of debris on the benthic fauna were frequently recorded, with 28.5% of the litter entangling corals and impacting habitats of conservation concern. These impacts were exclusively caused by the derelict fishing gear (91.2% by longlines), and the highest percentage (49.1%) of ALDFG causing impacts was observed from 41 to 80 m depth, in the coralligenous biocenosis. The results of the present study will help the fulfilment of "harm" monitoring, as recommended by the Marine Strategy Framework Directive (MSFD) and the UN Environment/MAP Regional Plan on the marine litter management in the Mediterranean Sea. Regarding the actions to reduce the derelict fishing gear, preventive measures are usually preferred instead of the extensive removals based on cost-effectiveness and sustainability. The establishment of a new MPA in the area could be a good solution to reduce ALDFG, resulting in the improvement of the ecological status of this coastal area.

Marine litter in south Bay of Biscay: Local differences in beach littering are associated with citizen perception and awareness

Marine litter is often left by beachgoers. Thus, understanding beachgoers' perception and awareness is important. In this study, the amount and type of litter was measured from nine beaches of central south Bay of Biscay (Spain), and a survey about perception and awareness of the beach littering was conducted among beachgoers. The region could be considered moderately littered compared with other studies, with significant differences among beaches for litter amount and types. Plastic was the most abundant item, followed by fishing gear. Differences among beaches for awareness and litter perception correlated significantly with differences in litter amount. Perception was positively correlated with beach frequentation. Significant gender differences were found, males taking more actions against litter than females regardless how much litter they perceived. These results could be employed for designing campaigns of beach litter treatment and awareness raising, by taking into account local differences detected in this study.

Technologies for the marking of fishing gear to identify gear components entangled on marine animals and to reduce abandoned, lost or otherwise discarded fishing gear

Fishing gears are marked to establish and inform origin, ownership and position. More recently, fishing gears are marked to aid in capacity control, reduce marine litter due to abandoned, lost or otherwise discarded fishing gear (ALDFG) and assist in its recovery, and to combat illegal, unreported and unregulated (IUU) fishing. Traditionally, physical marking, inscription, writing, color, shape, and tags have been used for ownership and capacity purposes. Buoys, lights, flags, and radar reflectors are used for marking of position. More recently, electronic devices have been installed on marker buoys to enable easier relocation of the gear by owner vessels. This paper reviews gear marking technologies with focus on coded wire tags, radio frequency identification tags, Automatic Identification Systems, advanced electronic buoys for pelagic longlines and fish aggregating devices, and re-location technology if the gear becomes lost.