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The ecological and socioeconomic problems caused by abandoned, lost and discarded fishing gear (ALDFG) are increasingly of concern. Marine gillnets and trammel nets, which have relatively high ghost fishing potential, are globally important gear types. Used primarily by coastal, artisanal, small-scale fisheries worldwide, gillnet and trammel net fi...
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... the 1960s, nets have been made with synthetic twine usually of nylon (polyamide), either as multifilament thread or monofilament or mutlimonofilament line, which is much less visible, more durable and requires less maintenance than nets made of non-synthetic fibre (Moore, 2008;Macfadyen, Huntington and Cappel, 2009). Mesh size is typically measured as the length of a whole stretched mesh (Figure 2), or Measuring mesh size as the length of a whole stretched mesh Source: SEAFDEC. as the half-length (bar-length). ...
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... There are multiple factors responsible for the formation of ghost nets or ALDFG. These are (i) damage nylon fishing nets during fishing operation on board,(ii) damage occur during tropical cyclone, (iii) damage due to strike with propeller, (iv) damage due to bottom obstacles such as coral reef system or any other hard structure, (v) mighty waves of the sea and ocean, (vi) weak or poor standard of fishing nets, (vii) accidental entanglement of large marine fauna such as whales, sharks, dolphins, sting rays or jelly fish etc, (viii) intentional thrown out of fishing net when clogged with raw fish materials such as Puffer fish Diodon sp., jelly fish bloom conglomeration (ix) non-commercial trash fish catch en masse etc, (x) Less expensive fishing gear with improved material durability and design (Gilman et al., 2016 ). Prevalence of ghost net in the marine is due to its buoyant nature, fishing net coloration mimics to sea water, easily transportable along the sea water current and tidal incursions. ...
Discarded fishing nylon nets, also known as derelict fishing gear or ghost nets, are one of the major components of the marine plastic litter that ultimately turns into a major cause of mortality to the marine macro and mega faunal communities. These organisms are not able to escape out are eventually killed thus such abandoned nets become potential killer trappers. Since these nets are made up of nylon, therefore non-biodegradable in nature remain in the sea for a longer period of time subsequently enters in to the marine food chain after fragmentation (microplastic). Predominantly entangled animal taxa in the derelict fishing gear are broadly grouped under crabs and horseshoe crabs, lobsters, stomatopods, prawns, gorgonids, sea turtles, fish, sea horses, dolphins, sharks, whales etc. Some of them are grouped under vulnerable, endangered or threatened category of IUCN. In this regard, the present study was conducted at the South Odisha Coast of India. On numerous occasions, unintended catch of marine organisms was observed with discarded nylon fishing nets from the year 2020 to 2022. The relative abundance calculated for the eleven observations made at South Odisha adjoining the Bay of Bengal reveals that at least 10 such faunal groups have been discovered; those are instantly caught in the derelict fishing gear. The relative abundance of trapped marine organism is: crabs and other crustaceans 20%, gorgonids 14%, fishes, stingrays and skates 28%, gastropods 10%, jellyfish 4%, bivalves and starfish equally contributed 6 % each, sea turtle hatchling 2%, hard corals 3%, miscellaneous taxa 7 % including horseshoe crabs and sea horse. Gorgonids, crabs, echinoderms and fishes are among the mostly trapped organisms. Albeit the present study is a preliminary attempt to create major baseline information however it will further helpful for developing proper management strategies to conserve the marine biodiversity.
... Abandoned, lost, or otherwise discarded fishing gear (ALDFG), a considerable contributor to global marine litter (Gilman et al., 2016), can have damaging negative effect on the marine environment. Most of the currently used fishing gear typically is made of non-biodegradable plastic materials with high breaking strength and durability to provide high catch efficiency for marine capture sector (Sauer et al., 2021;Yu et al., 2023a). ...
... ALDFG-induced ghost fishing can affect both target and non-target species, undermining fishery sustainability and economic viability (Gilardi et al., 2010;Antonelis et al., 2011). Passive fishing gear like gillnets, trammel nets, and pots or traps, poses a high ghost fishing risk, primarily due to their capture process dependent on fish swimming into the gear (Gilman et al., 2016;Sauer et al., 2021). ...
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.
... Ghost fishing catch was observed in 75 % of the retrieved ALD gillnet fleets and 64 % of the recovered king crab pot lines. Consistent with existing literature (Gilman et al., 2016;Lively and Good, 2019), regarding the potential ghost fishing impact of ALD gillnets and king crab pots. One possible explanation for the lower catch probability in retrieved ALD king crab pots is the absence of bait, attributed to the extended residence time of the pots in the marine environment (Cerbule et al., 2023). ...
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.
... The region contends with a soaring exploitation rate (0.71) driven by fervent demand, amplifying the risk of depleting BSC stocks. This heightened exploitation poses a direct threat to reproductive success, potentially leading to an ecosystem imbalance and hampering the long-term sustainability of BSC populations (Gilman et al., 2016;Do and Armstrong, 2023). A critical revelation from the study is the Spawning Potential Ratio (SPR) value of 19%, indicating significant overfishing in East Lampung. ...
In response to the escalating demand for blue swimming crabs (BSC) and the consequential impact on their habitat and population, this study advocates for sustainable management through a holistic approach. Our comprehensive framework integrates ecological conservation, socioeconomic well-being, and governance principles, aiming to establish a policy framework for the sustainable management of BSC in the Eastern Coast of Lampung. The research emphasizes the urgent issue of overexploitation, with an exploitation rate of 0.71, requiring immediate attention to prevent stock depletion and maintain ecosystem health. Findings reveal that male BSC, measured by carapace width, typically reaches the length at first catch (Lc50) at approximately 118.69 mm, while for females, it is about 122.70 mm—indicating that BSC is often caught larger than the 10 cm legal requirement set by the Ministry of Marine and Fisheries of Indonesia. Economic analysis demonstrates the profitability of the blue swimming crab business on Lampung's east coast, with a favorable crab capture per trip (4.63) and total costs ratio (1.18). The study area, featuring an extensive mangrove forest, hosts a crucial crustacean population, contributing significantly to BSC's diet. Beyond ecological significance, mangrove conservation enhances our understanding of environmental sustainability, particularly in carbon stock contributions. Addressing sustainability challenges requires a multi-faceted approach, including precise fishing technologies, effective regulation enforcement, and improved monitoring. Collaborative efforts among government authorities, fishing communities, and conservation groups are essential for balancing economic interests with the long-term ecological health of BSC populations in the study area.
... The region contends with a soaring exploitation rate (0.71) driven by fervent demand, amplifying the risk of depleting BSC stocks. This heightened exploitation poses a direct threat to reproductive success, potentially leading to an ecosystem imbalance and hampering the long-term sustainability of BSC populations (Gilman et al., 2016;Do and Armstrong, 2023). A critical revelation from the study is the Spawning Potential Ratio (SPR) value of 19%, indicating significant overfishing in East Lampung. ...
In response to the escalating demand for blue swimming crabs (BSC) and the consequential impact on their habitat and population, this study advocates for sustainable management through a holistic approach. Our comprehensive framework integrates ecological conservation, socioeconomic well-being, and governance principles, aiming to establish a policy framework for the sustainable management of BSC in the Eastern Coast of Lampung. The research emphasizes the urgent issue of overexploitation, with an exploitation rate of 0.71, requiring immediate attention to prevent stock depletion and maintain ecosystem health. Findings reveal that male BSC, measured by carapace width, typically reaches the length at first catch (Lc50) at approximately 118.69 mm, while for females, it is about 122.70 mm-indicating that BSC is often caught larger than the 10 cm legal requirement set by the Ministry of Marine and Fisheries of Indonesia. Economic analysis demonstrates the profitability of the blue swimming crab business on Lampung's east coast, with a favorable crab capture per trip (4.63) and total costs ratio (1.18). The study area, featuring an extensive mangrove forest, hosts a crucial crustacean population, contributing significantly to BSC's diet. Beyond ecological significance, mangrove conservation enhances our understanding of environmental sustainability, particularly in carbon stock contributions. Addressing sustainability challenges requires a multi-faceted approach, including precise fishing technologies, effective regulation enforcement, and improved monitoring. Collaborative efforts among government authorities, fishing communities, and conservation groups are essential for balancing economic interests with the long-term ecological health of BSC populations in the study area.
... However, the same material properties also enable the gear to continue capturing marine animals for years in case of being lost at sea, a process called "ghost fishing" (Matsuoka et al., 2005). Ghost fishing caused by ALDFG can affect both target and non-target species, including those classified as endangered, threatened, and protected (Gilman et al., 2016). Ghost fishing mortalities resulting from ALDFG are recognized as a significant source of wastage and negatively affect the sustainability and economic effectiveness in the marine capture sector (Gilardi et al., 2010;Antonelis et al., 2011). ...
... Passive fishing gear, such as gillnets, trammel nets, and pots or traps, exhibits the highest potential for ghost fishing, primarily because their capture process relies on fish swimming into the gear (Gilman et al., 2016). Therefore, this process can continue also after all control over the gear is lost (Hubert et al., 2012) as is the case in ALDFG. ...
... Due to the growing concerns for marine environmental and ecological conservation, Chinese Ministry of Agriculture and sea-related trade associations, research institutes, universities, and enterprises nationwide have taken a joint initiative in 2023 to explore effective strategies to manage and control ALDFG (Chinese Ministry of Agriculture, 2023). Considerable efforts are also being made globally to alleviate environmental issues by ALDFG such as preventive methods by avoiding and minimizing the incidences of gear loss, and approaches for reducing the longevity of ALDFG (Gilman et al., 2016). Development and use of environmentally friendly biodegradable plastic materials in fishing gear has emerged as a promising strategy to reduce the marine plastic pollution and limit ghost fishing. ...
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.
... Abandoned, lost or otherwise discarded fishing gear (ALDFG) is a type of marine plastic litter that is very prevalent, especially due to increases in fishing activity and gear durability over the last 50 years (Macfadyen et al., 2009;Watson, 2012). Approximately 1% of fishing gear per ship is lost each year (Gilman et al., 2016), being transported through currents before snagging or sinking (Katsanevakis, 2008). Rocks and coralline structures provide habitat for diverse species and thus are often heavily fished, so fishing gear is found to concentrate on such rugose features (Savini et al., 2014;Tubau et al., 2015;Melli et al., 2017;van den Beld et al., 2017;Consoli et al., 2018a;Angiolillo et al., 2022). ...
Litter is ubiquitous in the ocean, interacting with fauna and causing impacts that are unquantified at present. Mainly sourced from land, marine litter is very persistent, and undergoes slow degradation upon settling on the ocean floor. Submarine canyons contain more litter than other oceanographic features due to hydrological processes, but study of litter in canyons is made difficult by logistical requirements. Monitoring and quantification of marine litter often do not consider interactions between fauna and litter, meaning impacts are largely unconsidered and unknown. Among publications that have reported litter-fauna (L-F) interactions in canyons, the large majority occur in the Mediterranean Sea, and the most reported interaction is of corals entangled in fishing gear. When it occurs, the reporting of L-F interactions is unstandardised, resulting in a lack of global comparison and trend analysis. A standardised, comprehensive framework for the reporting of L-F interactions has been created and includes 6 major categories: entanglement, ingestion, smothering, habitat provision, adaptive behaviour, and encountering (entanglement and smothering occur on abiotic features as well). Use of the framework will aid in research collaboration and creation of a global dataset of L-F interactions. Impacts resulting from interactions are plentiful, most coming from entanglement and smothering.
... One of the most important contributions by fisheries to this problem is through abandoned or lost fishing gear (ALDFG) whose global and regional effects are not fully known [25]. Artisanal fishery worldwide, which accounts for one-fifth of global marine fishery catches, has become a significant potential source of plastic pollution in the form of ghost nets due to the use of gillnets and trammel nets [26]. There is currently an international agreement for the development of preventive strategies to reduce the ALDFG [27] derived from small pelagic fishing activities. ...
The extractive context of artisanal fishing in Ecuador is very broad and diverse considering the different fishing equipment that is used to capture a very varied set of species. As part of this broad sector, there is a small pelagic fishery, which is in the Crucita parish of the Portoviejo canton and is a long-standing and economically very relevant resource for the community. The objective of this article is to analyze the environmental and management aspects of this fishery as aspects relevant to achieving sustainable exploitation. To this end, information was collected from the beneficiaries of the purse-seine fishing fleet with the use of a structured questionnaire. The results revealed that there is widespread ignorance of the environmental aspects that affect the conservation of ecosystems and marine bioresources. On the other hand, the fishermen are aware of a general need to implement management measures that guarantee the sustainability of their fishing. However, they consider that the current regulations are not adapted to the current local context. Finally, from the perspective of those involved, the implementation of minimum capture sizes as a management measure could guarantee the sustainable capture of the species.
... Marine pollution caused by lost or abandoned fishing gear can result in an environmental issue, namely, the continued capture of marine animals, also called ghost fishing (Brown and Macfadyen, 2007;Macfadyen et al., 2009;Gilman et al., 2016). Gears such as gillnets and pots have the highest ghost fishing potential, mainly because the capture process is dependent on the fish swimming into the gear (Macfadyen et al., 2009;Gilman et al., 2016). ...
... Marine pollution caused by lost or abandoned fishing gear can result in an environmental issue, namely, the continued capture of marine animals, also called ghost fishing (Brown and Macfadyen, 2007;Macfadyen et al., 2009;Gilman et al., 2016). Gears such as gillnets and pots have the highest ghost fishing potential, mainly because the capture process is dependent on the fish swimming into the gear (Macfadyen et al., 2009;Gilman et al., 2016). Besides gear loss, some types of fishing gear contribute to plastic pollution by wear and tear of gear components, for instance, bottom trawl and demersal seine . ...
... Gillnets are among the most important fishing gears in the world, commonly used by recreational and commercial fisheries (Gilman et al., 2016). A gillnet is a rectangular netting curtain of uniform mesh size that is stretched out in the water column by a floating headrope and a sinking footrope, whereby fish swim into the net without noticing it and are entrapped by the meshes (He and Pol, 2010;Savina et al., 2022). ...
Gillnets are among the most common fishing gears worldwide. They are often made of thin twine, which is prone to wear and tear, limiting the lifespan of the gillnet. This increases gillnet turnover, and consequently increased risk of gear discarding, gear loss, ghost fishing and marine pollution. This might be mitigated by increasing twine thickness, and thereby breaking strength. However, the tolerable increase in thickness for gillnet durability without compromising the catch efficiency is unknown. Therefore, this study conducted gillnet fishing trials under commercial conditions in the Northeast-Arctic cod gillnet fishery analysing and comparing ways of capture and efficiency between gillnets with two different twine thicknesses for two different mesh sizes. The results demonstrated that a 30 % increase in breaking strength and twine stiffness did not affect catch performance. Therefore, thicker gillnet twine can potentially reduce marine litter by plastic debris from damaged and lost gears without compromising catch performance.
... Containers made with polystyrene foam in Hong Kong as elsewhere are ubiquitous because they are cheap, lightweight and water and thermal resistant [15,8] . Although at a global scale, fishing gear is estimated to compose less than 10% of total marine debris by volume [16] , the degree of plastic fishing gear occurrence can be highly variable at smaller spatial scales when based on locality [17] . The impacts of marine debris (also known as abandoned, lost or otherwise discarded fishing gear (ALDFG), see Figures 6B, 6C, and 6D) derived from fisheries are particularly concerning in remote areas of Hong Kong and outlying islands, such as seen on Cheung Chau and Peng Chau coastlines as exhibited in Table 4 and Figure 6. ...
From data published by the Hong Kong SAR (HKSAR) government in their two sole fisheries surveys of 2006
and 2016/2017, the current authors produced regional maps using spatial interpolation to more accurately describe and
estimate the geographic coverage of changes in fishing production in Hong Kong waters since the ground trawl ban
of 2012 December 31st. These suggest the fishing industry has adapted to smaller craft, and that fishing production
increased in several areas in the period after the ground trawl ban came into effect. In addition, the maps enable a
smoother assessment to be made of the geospatial changes in fishing production which have occurred since the ground
trawl ban and suggest a ‘workaround’ by fishermen. In particular, small fishing craft known as sampans are able to
take advantage by being more suitable vessels for areas such as narrower or shallower bays. Marine plastics pollution
is also a proxy indicator of these activities, as evidenced by discarded fishing gear that includes plastic nets, floats, and
other fishing boat equipment.
Keywords: Fishing production; Commercial fishing; Marine plastics; Ground trawl ban
