Ghost Fishing Research Articles

EVALUATING POTENTIAL BIODEGRADABLE TWINE FOR USE IN THE BLUE SWIMMING CRAB COLLAPSIBLE POTS

This study addresses the global issue of lost fishing gear, specifically traps and pots, which rank second regarding gear lost in marine environments. These traps often contain synthetic fibers that decompose slowly, producing long-lasting ghost fishing. To mitigate this problem, the study explores using biodegradable materials in trap construction. The research focuses on assessing biodegradable materials' physical and mechanical properties and how immersion affects them. Field surveys and sample immersion were conducted at Kejawanan Fishing Port Cirebon, with subsequent testing at IPB University. The study compared three natural materials: cotton, agel, and hemp twines. The cotton twine stood out with its soft texture compared to the rougher agel and hemp twines. Regarding elongation, cotton 20.76% outperformed agel 13.70% and hemp 4.42%. Sequential breaking strength tests revealed cotton's superior strength at 9.84 kgf over agel at 3.61 kgf and hemp at 2.72 kgf, even after immersion. These findings indicate that cotton twine is a viable biodegradable alternative to synthetic twines in blue swimming crab pot fishing. By adopting such materials, fishermen can reduce the environmental impact of lost gear and contribute to more sustainable fishing practices.

Mitigating ghost fishing

Mitigating ghost fishing

Composition of lost and discarded fishing gear (ghost fishing) in the blue swimming crab fishery in Rembang, Central Java

Ghost fishing is the ability of fishing gear to catch fish continuously for a certain period when the fishing gear has been lost. Some passive fishing gear will most likely be lost due to material degradation of gear components and other factors. Therefore, it is necessary to study the composition of fishing gear left in the sea to find out the cause of ghost fishing. The study aimed to determine the composition of materials from fishing gear left in the waters of the Rembang Sea. This is done by collecting fishing gear found by fishermen and then weighing per material to get the composition of the fishing gear. As many as 86% are metal, and 14% are plastic. This shows that metal and plastic materials are difficult to decompose in marine waters, so fishermen still find these fishing gear in Rembang waters. This also shows that metal is the dominant constituent of the fishing gear used by fishermen in Rembang waters. This research provides information about what fishing gear materials are likely to be a source of ghost fishing so that it can be a suggestion for using fishing gear.

The new Marine Stewardship Council requirements to improve ghost gear management: Insights from the policy development process

Abandoned, lost or discarded fishing gear, otherwise known as ‘ghost gear’, impacts marine ecosystems in a variety of important ways. The growing recognition of these impacts has led to an evolution of fisheries management with a focus on gear loss avoidance and ghost gear mitigation. The Marine Stewardship Council has responded to the global ghost gear challenge through important revisions made to its Fisheries Standard during the recent Fisheries Standard Review (FSR). Fisheries certified against the Fisheries Standard will now be required to explicitly assess and manage their ghost gear impact on target stocks, on bycatch and on marine habitats - this outcome received strong support during public consultation undertaken for the policy development process. These changes are aimed implementation of best practice management strategies which emphasise gear loss preventative measures supplemented by mitigation and remedial action to minimise impact of ghost gear. The paper covers key insights of the policy development process which supported these changes including best practice research, policy design, public consultation, and impact testing. Conclusions of the policy process are discussed, included their likely implications for fisheries currently certified and those planning to seek certification against the MSC Fisheries Standard.

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.

Evaluation of sea turtle morbidity and mortality within the Indian Ocean from 12 years of data shows high prevalence of ghost net entanglement.

Anthropogenic activities can negatively affect sea turtle populations. Quantifying the effect of human actions on these threatened species can help guide management strategies to reduce adverse impacts. However, such assessments require extensive effort and resources and as such have not been carried out in many areas of important sea turtle habitat, including the Republic of the Maldives (Maldives). Here, we utilise 12 years of data (2010-2022) collected from marine turtle stranding and rehabilitation cases from across the Maldives to identify the key threats in this region. Olive ridley turtles were found stranded or injured most frequently (74.7% of total cases), along with hawksbill (15.2%), and green (10.1%) turtles. Anthropogenic factors were the primary cause of injury or stranding in 75.2% of cases with entanglement in ghost fishing gear being the most common (66.2% of all cases). Other causes of morbidity, such as from turtles being kept as pets (5.6%), boat strikes (<1%), bycatch (<1%), and poaching (<1%) were recorded less frequently. Olive ridley turtles were more likely to have injuries associated with entanglement than other species and showed a peak in admissions during the northeast monsoon, in the period following the known arribada nesting season in nearby India. Turtles admitted to rehabilitation following entanglement were released a mean of 70 days sooner and had 27.5% lower mortality rates than for other causes of admission. This study highlights the high prevalence of ghost net entanglement of sea turtles within the Maldives. The topic of ghost fishing is of global importance and international cooperation is critical in tackling this growing issue.

Biodegradability and sustainable fisheries: The case for static gear in the UK Channel fishery

Abandoned, lost or otherwise discarded fishing gear (ALDFG) is created by the fishing industry and directly impacts fishers’ livelihoods through ghost fishing, entanglements and presents navigational hazards. In addition, ALDFG creates a myriad of environmental and socioeconomic impacts that affect fisheries and other commercial sectors operating in the marine environment, as well as recreational users and land-based sectors e.g. tourism. Given the inefficiencies of current approaches to deal with ALDFG, urgent solutions are required. Biodegradability, as a design feature of fishing gear, is not a new idea, but it is one that requires further research to fully understand the potential role of biodegradable fishing gear (BFG) to mitigate (various) environmental and economic impacts of ALDFG. In this paper, we focus on the role of BFG in the Channel static gear fishery, engaging stakeholders through one-to-one interviews at the quayside to consider their views on the role of BFG in their fishery. This research demonstrates the complexity of the problem and the solution. By collecting the fishery’s concerns, enthusiasm and requirements regarding BFG it adds a powerful new strand to the debate, moving it on from simply a ‘cost to replace’ to ensuring that it meets the detailed requirements of a fishery that relies on specificity to earn a living.

Biodegradation behavior of polybutylene succinate (PBS) fishing gear in marine sedimentary environments for ghost fishing prevention

This study evaluated the biodegradability of PBS fishing gear in marine sedimentary environments, which is a major cause of unintended catches caused by discarded fishing gear, known as “ghost fishing”. Based on the biodegradation analysis according to ISO 19679, the PBS fishing gear was converted into carbon dioxide by 27.3% for 180 days. After biodegradation, the remaining PBS exhibited a characteristic molecular weight decrease, indicating bulk erosion, but there was no change in crystallinity and thermal properties. Ultimately, degradation of the PBS proceeded primarily through surface abrasion with metabolic utilization of hydrolysis products by microorganisms. Biological studies showed that the Rhodococcus genus was the dominant microbe for PBS biodegradation. In an accelerated evaluation experiment using a lipase enzyme known to be produced by dominant bacteria, the PBS showed a high biodegradability of 48% in 10 days. From the perspective of biodegradation, biodegradable fishing gear can not only replace existing nondegradable fishing gear but also prevent ghost fishing through biodegradation in the marine sedimentary environment after use.

Ghost fishing efficiency by lost, abandoned or discarded pots in snow crab (Chionoecetes opilio) fishery

Marine pollution by lost, abandoned or otherwise discarded fishing gear (ALDFG) often has negative impact on the ecosystem through plastic pollution and continuous capture of marine animals, so-called “ghost fishing”. ALDFG in pot fisheries is associated with high ghost fishing risk. The snow crab (Chionoecetes opilio) pot fishery is conducted in harsh weather conditions increasing the risk of fishing gear loss. Due to plastic materials used in the pot construction, lost gear can most likely continue fishing for decades. This study presents a method to quantify ghost fishing efficiency relative to catch efficiency of actively fished pots. On average, the ghost fishing pots captured 8.29 % (confidence intervals: 4.33–13.73 %) target-sized snow crab compared to the actively fished pots, demonstrating that lost pots can continue fishing even when the bait is decayed. Given the large number of pots lost each year, the ghost fishing efficiency is a considerable challenge in this fishery.

Introduction to the Marine Policy special issue on abandoned, lost and discarded fishing gear: Causes, magnitude, impacts, mitigation methods and priorities for monitoring and evidence-informed management

The rapid expansion of the global footprint of marine capture fisheries over recent decades, combined with the transition to synthetic and more durable materials used for fishing gear components, has resulted in increasingly problematic adverse ecological and socioeconomic effects from abandoned, lost and discarded fishing gear (ALDFG). Adverse impacts include: ghost fishing; marine wildlife ingestion; distribution and transfer of toxins and microplastics into marine food webs; altered distributions and behavior of species that raft on or aggregate beneath floating ALDFG, including the transport of invasive non-native species and distribution of microalgae that cause harmful algal blooms. ALDFG also causes habitat degradation; obstruction and damage to maritime sectors such as from fouling marine vessels and damaging submarine cables and in-use fishing gear; and reduction of socioeconomic values of coastal areas. There has been growing recognition of the need for improved understanding and evidence-informed management of these adverse effects. The articles composing the Marine Policy special issue on ALDFG contribute to achieving this goal. The articles improve the understanding of key requirements for robust, effective ALDFG monitoring and management. This includes knowledge of ALDFG direct causes and underlying drivers, rates and magnitudes of production, composition, fate, ecological and socioeconomic impacts, and criteria for selecting fishery-specific management strategies, which we review in this introduction to the special issue.

University-driven coastal partnerships to address ghost gear pollution: A case study in Penghu Islands of Taiwan

Ghost gear has become a significant environmental and economic challenge affecting oceans worldwide. Preventing and eliminating ghost gear is essential for achieving sustainable development goals (SDGs), and partnerships between universities and multi-stakeholders are considered feasible solutions. This case study illuminates the implementation of the Partnerships for Ghost Gear Cleanups & Education Project (PGGCEP) conducted by the National Kaohsiung University of Science and Technology (NKUST) in the Penghu Islands of Taiwan, which involves engagement with local stakeholders to prevent and remediate ghost gear in Penghu seas, providing insights into coastal partnerships building to promote ocean sustainability. The conceptual schemes of PGGCEP include education projects, marine citizenship practices, and awareness campaigns. The outcomes of PGGCEP were analyzed under the framework of SDGs. The results showed that PGGCEP not only successfully supported SDG 14 life below water through the achievement of SDG17 partnerships for the goals, and it also contributed to other SDGs, including SDG 4 quality education, SDG 5 gender equality, SDG 8 decent work and economic growth, and SDG 10 reduced inequalities. Future directions for PGGCEP were subsequently provided to refine the project. Based on the findings, this study proposed a framework of university-driven coastal partnerships to address ghost gear pollution. This 4-phase framework highlights the pivotal role played by universities as facilitators of collaborative efforts that involve a broad spectrum of stakeholders for enhancing ocean sustainability.

Study for the Detection of Ghost Nets in the Sea of Marmara (Kapıdağ Peninsula and Islands Region)

Bu çalışma Marmara Denizi’nde (Kapıdağ Yarımadası ve Adalar Bölgesi) hayalet ağların yerini ve miktarını belirleyerek, uygun dalış limitleri içerisindeki kaybolan av araçlarını çıkarmak için gerçekleştirilmiştir. Bu amaçla, bölgede faaliyet gösteren balıkçılar ve balıkçı kooperatifi başkanları ile 168 adet anket yapılmış olup bunların 42 tanesi tarafından kaybolan ağların yerleri ile ilgili geri dönüş alınmıştır. Dalışa uygun 10 istasyonda 32 dalış operasyonu gerçekleştirilmiş olup, toplam 20 saat dip zamanı harcanmış ve 43500 m2 alan taranarak, 1 adet trol takımı, 1 adet algarna takımı, 18, 500m2 gırgır ağı, 200m uzatma ağı, 2 adet paragat takımı, 8 adet gemi çapası, 500m marya ağı, 1 adet ahtapot oltası ve parça uzatma ağları ile olta iğneleri çıkarılmıştır. Anket sonuçları değerlendirildiğinde, dalış yapılarak çıkarılan bu av araçlarının Marmara Denizi’nde (Kapıdağ Yarımadası ve Adalar Bölgesi) kaybolan av araçlarının sadece %1‘lik kısmı olduğu tahmin edilmiştir.

Environmental Degradation of Nylon, Poly(ethylene terephthalate) (PET), and Poly(vinylidene fluoride) (PVDF) Fishing Line Fibers

Ghost fishing, caused by lost fishing lines and nets, has become a severe problem in marine environments. To eliminate ghost fishing in the ocean, the environmental degradation behavior of fishing lines must be understood. In this study, the environmental degradation of biodegradable nylon 4 fishing lines and commercial nylon 6, poly(ethylene terephthalate) (PET), and poly(vinylidene fluoride) (PVDF) fishing lines was simulated in the laboratory using an artificial weathering tester and biodegradation test in extracted seawater. To understand the degradation mechanism, the chemical and structural changes induced by photo-oxidation and biodegradation were investigated using tensile test, scanning electron microscopy, differential scanning calorimetry, gel permeation chromatography, infrared spectroscopy, and wide- and small-angle X-ray scattering. The results indicated that photo-oxidation occurred in the amorphous phase of the nylon 4, nylon 6, and PET fishing lines during ultraviolet (UV) exposure. The nylon 4 fishing lines exhibited excellent biodegradability, whereas the nylon 6, PET, and PVDF fishing lines could not be degraded by microorganisms in the extracted seawater. Both processes, i.e., photo-oxidation and biodegradation, were confined to the amorphous regions of nylon 4. Note that the PVDF fishing lines could not be degraded by UV exposure and biodegradation and, hence, should be recycled after use.

Effect of gillnet twine thickness on capture pattern and efficiency in the Northeast-Arctic cod (Gadus morhua) fishery

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.

Microplastics Detected in Sediments and Rocks Substrate of Marine Areas with Ghost Nets

According to UNEP and FAO reports, the fishing nets abandoned in the seas around the world represent approximately 10% of the plastic waste present in the oceans. These nets, also called ghost nets, can be degraded over time, releasing microplastics and contaminating the environment. Studying the presence and amount of microplastics in an area impacted by ghost nets in the Gulf of Cefalù, northern coast of Sicily, Italy can help to understand the level of contamination in these zones. The planned study methodology has been carried out by sampling sediment and rock substrate, on a quantitative basis, by scuba diving at seven stations selected as the most representative for the presence or absence of fishing nets in the study area. Two different extraction methods for sediment and rock samples were taken from the literature and modified for the present study. Microplastics determination was carried out according to, first, a visual identification and, second, a polymer type identification by ATR-FTIR spectroscopy, demonstrating the presence of polyamide, nylon, or polyethylene in the impacted areas, probably derived from the degradation of fishing nets. The present study reports the first record of microplastics determination in rock substrate samples recollected by scuba diving activities.

Small innovation for sustainable use of fisheries resources

Influenced by Rio Declaration, Code of Conduct for Responsible Fisheries provided the principle toward sustainable fisheries in 1995. Reduction of wastages became a major issue. The author first accessed that the total amount of finfish discards in prawn trawling was similar to the coastal fisheries’ production in PNG and it was serious wastage. He also proved the over-estimation of global discards. A newly developed semi-demersal cuttlefish trammel-net successfully excluded bycatch of sub-legal individuals of flounder. He clarified that the process of declining of ghost fishing function after gear loss for cage trap and gillnet is represented with a survival function, on which the duration of ghost fishing and mortality were quantitatively estimated. He developed a technique for buoy line with an intermediate float to avoid entanglement of the line around seabed rocks. The author advocates research toward small innovation, through which many researchers can contribute to sustainable development.

Marine Litter in The Perception of a Group of Fishermen

Marine litter is a serious environmental problem and directly affects fishing activities. Otherwise, these activities contribute to the increase of marine litter with the abandoned, lost or otherwise discarded fishing gear (ALDFG), causing what is known as ghost fishing, responsible for the death of thousands of animals in marine environments. So, the present study sought to assess the profile and the perception about marine litter of fishermen from the Z7 colony, on Itaipu beach, an oceanic region of Niterói, Rio de Janeiro, Brazil. The evaluation was carried out through the application of an open questionnaire to 30 fishermen. The results indicated that despite observing the increasing pollution on marine environments and identifying the main pollutant, most of the interviewees only identify the impacts of the marine litter on their own work (fishing), without pointing the environmental concern as a whole, exempting themselves from guilt regarding the responsibility for this pollution found in the marine environment. Thus, the need for environmental education activities and other actions with this fishing community is evident, in order to mitigate the impacts of this pollution on marine environments.

Improving sustainable practices in tuna purse seine fish aggregating device (FAD) fisheries worldwide through continued collaboration with fishers

More than a decade of bottom-up collaborative workshops and research with fishers from the principal tropical tuna purse seine fleets to reduce ecological impacts associated with the use of fish aggregating devices (FADs) has yielded novel improved sustainable fishing practices in all oceans. This integrative effort is founded on participatory knowledge-exchange workshops organized by the International Seafood Sustainability Foundation (ISSF), referred to as “ISSF Skippers Workshops”, where scientists, fishers, and key stakeholders examine and develop together ways and tools to minimize fishery impacts. Workshops organized since 2010 have reached fleet members in 23 countries across Asia, Africa, the Americas, Europe, and Oceania, with over 4,000 attendances, mostly skippers and crew, operating in the Indian, Atlantic, and Pacific oceans. Structured and continued open transparent discussions on ocean-specific options to minimize FAD associated bycatch, ghost fishing and marine pollution have produced an array of novel co-constructed solutions and a better understanding of ecosystem and fishery dynamics. Dedicated at sea research cruises in commercial purse seiners have enabled testing some of the ideas proposed in workshops. Results obtained were then communicated back to fishers for a double loop learning system resulting in solution refinement and/or adoption. Furthermore, fishers’ increased trust and stewardship have stimulated unprecedented large-scale science-industry research projects across oceans, such as multi-fleet biodegradable FAD trials, the adoption and widespread use of non-entangling FADs, and the development and adoption of best practices for the safe handling and release of vulnerable bycatch. This model of collaborative research is broadly applicable to other natural resource conservation fields. Support for long-term inclusive programs enabling harvesters to proactively collaborate in impact mitigation research contributes to improved scientific advice, voluntary compliance, and adaptive management for lasting sustainability trajectories.

Ghost fishing gear and their effect on ecosystem services – Identification and knowledge gaps

Abandoned, lost, and discarded fishing gear (ALDFG) is claimed to be a global problem with impacts on marine animals and ecosystems, posing considerable ecological and socioeconomic challenges. Nonetheless, insufficient understanding regarding how marine ecosystem services are affected by ALDFG creates a knowledge gap that challenges a holistic estimation of the long-term economic impacts of using non-degradable fishing gear. In this study, a systematic review and meta-analysis of the existing literature on ALDFG and ghost fishing is conducted, with the aim to assess findings in the literature and identify knowledge gaps. 90 published works were included in the systematic review, of which 67 were examined further in the meta-analysis. We identified a limited number of economic studies, as well as research from developing countries. Focus is largely on ghost fished commercial species, while other species, and non-use values are largely ignored. Though provisioning, supporting and cultural services are represented in the studies, regulating services impacted for instance by the marine plastic pollution of ALDFG, received no attention. Expanding research to include more of these currently lacking elements may be vital for efficient management in relation to ALDFG.

Ghost fishing capacity of lost experimental gillnets: a preliminary study from Indian waters.

Abandoned, lost, or otherwise discarded fishing gear contributes considerably to global marine debris. These lost gears, mostly made of non-biodegradable synthetic materials, persist in the marine environment for longer periods of time and pose a great threat to marine life by entangling and killing target fishes and other non-target species such as turtles, birds, and mammals, a phenomenon known as ghost fishing. Other environmental impacts include physical impacts on aquatic habitats, transfer of microplastics into food web, and interference with fishing. Information regarding the catching efficiency and catch rates of lost nets in Indian waters is lacking. Ghost fishing capacity of simulated lost gillnets is being reported for the first time in India. This study investigates the ghost fishing capacity of lost gillnets through an experimental approach at Aroor, Vembanad lake, Kerala, India. Simulation studies using purposefully abandoned shrimp gillnets (32mm mesh size) were conducted to understand the fishing capacity of lost gillnets during two seasons (monsoon and post-monsoon) as separate experiments. The gillnets maintained their catching efficiency until the 15th day during the first experiment and up to the 50th day in the second experiment. Catches showed an exponential reduction over time in both experiments. A total of 251 specimens comprising of 27 species were caught from both sets of experimental nets, and the state of catch in the nets showed different decaying stages from the second day itself along with fresh stages. As the days progressed, particulate matter and detritus began to accumulate on the experimental nets, increasing net visibility and reducing their catching efficiency. The results of the study on ghost fishing capability will contribute to the development of strategies for reducing the effects of lost nets on the aquatic ecosystem and for suggesting improved management strategies.