Could the obligation to land undersized individuals increase the black market for juveniles: evidence from the Mediterranean?

The latest Green Paper on the EU Common Fisheries Policy (CFP) identified the high level of discards in Europe as one of the structural weaknesses of the current CFP. The new CFP introduces a discard ban in European waters, with an obligation to land all regulated species. The fishing management system in the Mediterranean is based on effort control and technical measures, and this is raising some particular concerns about the effective implementation of the discard ban. With the exception of bluefin tuna (Thunnus thynnus, Scombridae), there are no quotas in the Mediterranean and this regulation affects all regulated species with the minimum landing size. Under these circumstances, the discard ban may lead to an increase in the amount of juvenile fish caught, because such catches are not counted against a given quota, as is the case in the Atlantic fisheries, and thus, there is no incentive to avoid catching them. On the contrary, the obligation to land the juveniles that are now discarded and their subsequent fishmeal processing might even become commercially interesting. One possible consequence of the new regulation may be an increase in the illegal marketing of fish below the minimum size. The landing, storage and transportation of juveniles will all be legal, and this may simplify their commercialization via the black market. The discard ban and landing obligation should be accompanied by other measures to ensure their successful implementation, including the agreement of the fishing sector to comply with the rules and regulations.     

Constructing indices to detect temporal trends in discarding

Discards refer to the part of the catch not retained on board during commercial fishing operations, and returned to the sea. With numerous legislation, policies, and resolutions in place that seek to minimize or eliminate discards, performance indicators are required to measure progress towards this objective. Indices of discards were developed for the purpose of illustrating changes in overall discard patterns over time. A discard quantity index provides annual changes in total discard quantity, a discard rate index and discard proportion indices demonstrate how discarding behaviour during fishing operations changes with time. Knowledge of the consistency in the reporting of fishing effort and landings as well as in the sampling programme is important in identifying genuine trends. The indices examined show their potential as useful tools as indicators of changing discard patterns and were most powerful when used in combination. By utilizing data from the observer programme for England and Wales, a reduction of 61% between 2002 and 2008 in the weight of discards could be demonstrated. In this case study, the reduction in discard weight could be attributed to reducing levels of fishing effort and diminishing catch weights.     

Climate variability impact on Bali sardine fishery: Ecology and fisheries perspective

The sardine fishery in Bali is influenced by fishing effort and environmental conditions including temperature and chlorophyll a (chl‐a). Bali's sardine, Sardinella lemuru Bleeker, production decreased significantly during the extreme conditions that occurred in 2010 and 2016. This study assesses the impact of extreme conditions on the sardine fishery of the Bali Strait. Fisheries data were collected from two landing places: Muncar fishing port (Banyuwangi District, East Java Province) and Pengambengan fishing port (Jembrana District, Bali Province) between January 2007 and December 2017. Temperature and chl‐a data were downloaded from satellite readings. Fishing locations were observed by an onboard observer to investigate shifts in fishing grounds. A modified Cobb–Douglas regression model and profile analyses were used to estimate the impact of environmental variables on sardine production and to assess how extreme periods affect the catch composition in the Bali Strait. Seawater temperature and chl‐a concentration had significant impacts on sardine production, but temperature is likely to be less correlated with sardine production than chl‐a concentration. To adapt to extreme weather, purse seiners prefer to modify the vessel type rather than change their fishing ground.     

Discarding practices in a Mediterranean small-scale fishing fleet (Patraikos Gulf, Greece)

Abstract  Discarding practices from 110 fishing operations in a Mediterranean small-scale fishing fleet (Patraikos Gulf, western Greece) from August 2004 to July 2005 were analysed. On average, 1 kg of fish was discarded per fishing operation (10% of the catch). The reasons for discarding were: low commercial value (78% of discards), damage at sea before retrieval of the gear (5%), and bad handling on-board (17%). More than half of discards belonged to Spicara flexuosa (L.), Lepidopus caudatus (Euphrasen), Sardinella aurita Valenciennes and Merluccius merluccius (L.). The bulk of discards of each species were associated with a single fishing method (metier). A Generalized Linear Model (Delta-X – error-model) indicated that, when discards were present, significant differences existed in the discard ratio among different métier groups (groups comprising métiers with similar characteristics). Longlines and trammel nets with small mesh-sizes had the highest discard ratios. Discarding practices for the species Diplodus annularis (L.), S. aurita , Squilla mantis (L.), S. flexuosa and Scorpaena scrofa (L.) did not follow a consistent pattern (these species were either fully discarded or fully retained during a fishing operation). The decision seemed to be dependent on market demands rather than fish size. Significant correlation was found between discarded and catch weight, but the presence of many outliers indicated deviance from a case where discards are high when there is an abundant catch. The findings of the study imply that monitoring and management should be carried out preferably on the métier level. Discards could be reduced by technical measures, controlling effort regulations and by improving working conditions on-board fishing vessels.     

Approaches to fully documented fisheries: practical issues and stakeholder perceptions

The Common Fisheries Policy (CFP) reform sets out a move to a land‐all catch policy in European Union waters with a requirement for full reporting of fishing and on‐board processing activity. We explore the merits, stakeholder perceptions and applicability of different technology and approaches to the full documentation of fisheries that might be considered in the context of implementing the CFP reform. While recent efforts have focused on demonstrating how remote electronic monitoring (REM) systems can be utilized in fully documented fisheries (FDF), other technologies and approaches such as reference fleet and self‐sampling exist that could contribute to delivering FDF. Perceptions of fishers show that they would prefer using a reference fleet or self‐sampling to REM systems as a future method of implementing FDF. In general, there is support from the fishing industry for data collection and enhancement, but there remains some mistrust concerning the use of the data. Findings show that the most appropriate means and methods of FDF will depend on the circumstances and objectives for full documentation whether in enforcing a discard ban, documentation of total catch or data enhancement. We conclude that any technology or approach that will be used to deliver the monitoring requirements for FDF needs to make practical and commercial sense at the fishing vessel level.     

Managing by‐catch and discards: how much progress are we making and how can we do better?

There appears to be considerable potential for further reduction in global by‐catch. This reduction is most likely to be achieved by focusing even greater attention on the technical, regulatory and social approaches that are currently practiced. With respect to the technical approaches, meta‐analysis indicates that overall reductions in by‐catch of between 25% and 64% could be achieved if global fishing fleets could match somewhere between the minimum and median performance of gear modifications used in experimental studies. If such benefits are to be delivered, however, engaging fishers more comprehensively in solving the problems will be essential. Further developing legislative and institutional arrangements will also assist. However, notwithstanding the potential gains that can be achieved, it must be recognized that careful analysis will often be required to ensure that a proposed measure will achieve the desired objective at an acceptable cost.     

New mitigation measures reducing seabird by‐catch in trawl fisheries

This paper provides an update on an earlier review [Fish & Fisheries 8 (2007) 31] of mitigation methods used to reduce seabird by‐catch in trawl fisheries. Interactions of seabirds with trawl vessels fall into two broad categories: those focused on the trawl warps and those focused around trawl nets. For reducing seabird strikes on trawl warps, the use of bird‐scaring lines has been proved to be the most effective mitigation device in the trawl fisheries in which comparative studies have been undertaken. However, the retention or strategic management of fish waste (offal and discards) is recommended as the most effective primary measure for by‐catch reduction, and as such should be viewed as the best long‐term solution to reducing seabird by‐catch in trawl fisheries. Coincident with effective fish waste management, measures such as cleaning the net prior to shooting and reducing the time the net is on the surface should be viewed as best practice measures and incorporated into normal fishing activities. While a number of methods have been trialled to reduce the incidence of warp strikes, there continues to be the need for more work on effective measures for reducing interactions of seabirds with the trawl net.     

Reforming the European Common Fisheries Policy: a case for capacity and effort controls

I summarize the total allowable catch (TAC) fishery management system, which forms part of the European Common Fisheries Policy (CFP) as complicated, inaccurate and ineffective. Total allowable effort (TAE), i.e. limits on fishing capacity and days‐at‐sea, provides a simpler, readily enforceable control to protect all species affected by a fishery. Fishing capacity of vessels in each region‐gear fleet could be capped through limits on engine power, gear, crew, and fittings, and/or reducing allowances of days‐at‐sea for large, powerful vessels. Two basic, fishery‐dependent indicators are put forward to assess sustainability of a fishery dependably even in the absence of fishery‐independent data. One is socio‐economic, the other is ecological. Fishery working groups within each marine region would recommend a TAE to sustain their fishery while also protecting the most critically affected species or processes. Regional working groups would supervise a consistent approach across the different fisheries in their region. A pan‐European group would set policy, implement external agreements, set rules for trading TAE if necessary and harmonize fishing opportunities across regions. To ease negotiations on TAEs with the fishing industry when an ecosystem needs to recover, I propose compensation payments funded by re‐direction of existing CFP subsidies that promote fishing.     

Environmental Non‐Governmental Organizations and the Common Fisheries Policy

1. The run up to the review of the European Union's (EU's) Common Fisheries Policy (CFP) in 2002 affords a timely opportunity to examine the impact of one lobby—the environmental lobby—on its operations. 2. The conventional view of the CFP is that it is driven primarily by economic objectives, and that environmental considerations take a back seat. The CFP is broadly concerned with maximizing output, employment and income from the fishery within the constraints imposed by the biological state of the stocks. 3. However, there are indications that this picture is changing and that the CFP is beginning to take account of the environment. Some of the credit for this change must go to Environmental Non‐Governmental Organizations (ENGOs) which have recently been campaigning heavily for more effective management of commercial fishing. But the success that they have had so far appears to be mainly confined to single issues, such as the drift‐net ban. 4. In the bigger battle, for protection of the entire marine ecosystem against the damage caused by fishing, ENGOs have yet to achieve a significant breakthrough, though there are some signs that the tide is slowly turning in their favour on this wider issue. Copyright © 2000 John Wiley & Sons, Ltd.     

The evolution of a discard policy in Europe

Ocean sustainability is a widespread public concern in Europe, and the issue of fisheries discards is one that is now widely known. With this increase in public awareness comes the need to adapt fisheries management policies to manage issues like fisheries discards that were not previously taken into account. In this context, this study analyses the evolution of the European Union's discard policy since its inception in 2006 until the present day and the events that shaped its current format. It analyses the policy's advantages and disadvantages, and its political, environmental and scientific consequences. It argues that an increase in public awareness, due to public campaigns against fisheries discards, has focused managers' attention onto a symptom of fisheries mismanagement, rather than on its underlying causes of over‐exploitation and lack of fisheries control. This has distorted the discussion of the reform of the Common Fisheries Policy and potentially undermined its provisions relating to discards.     

Empirical move‐on rules to inform fishing strategies: a New England case study

Increasingly, fisheries are being managed under catch quotas that are often further allocated to specific permit holders or sectors. At the same time, serious consideration is being given to the effects of discards on the health of target and non‐target species. Some quota systems have incorporated discard reduction as an objective by counting discards (including unmarketable fish) against the overall quota. The potential effect of the introduction of a quota system that includes accountability for discards on the fishing strategies employed by fishermen is enormous. This is particularly true for multispecies fisheries where healthy and depleted stocks co‐exist; resulting in a trip's catch being applied to very large and very small stock quotas simultaneously. Under such a scenario, fishermen have a strong incentive to minimize (i) catch of low‐quota or ‘choke’ stocks, (ii) regulatory discards due to minimum size limits and (iii) catch partially consumed by predators. ‘Move‐on’ rules (i.e. event‐triggered, targeted, temporary closure of part of a fishery when a catch or bycatch threshold is reached) have been employed in a variety of fisheries. However, their efficacy has been limited by a lack of empirical analyses underpinning the rules. Here, we examine the utility of spatiotemporal autocorrelation analyses to inform ‘move‐on’ rules to assist a sector of the New England Multispecies Fishery to reduce discards and maximize profits. We find the use of empirical move‐on rules could reduce catch of juvenile and choke stocks between 27 and 33%, and depredation events between 41 and 54%.     

Benefits,concerns, and solutions of fishing for tunas with drifting fish aggregation devices

Drifting fish aggregating devices (dFADs) are human-made floating objects widely used by tropical tuna purse seine (PS) fisheries to increase catch of target species. However, dFAD use has several negative impacts, including increased potential for overfishing, higher juvenile tuna catch, higher bycatch compared to other PS fishing modes, ghost-fishing, and generation of marine litter. Based on these impacts, some stakeholders, especially environmental non-governmental organizations and other competing fishing industries, suggest that dFADs should be completely banned. We list the pros and cons of dFAD fishing; address how to improve current management; and suggest solutions for the sustainability of dFAD fishing in the long term. A dFAD ban would lead to major changes in the availability and sourcing of tuna for human consumption and decrease the licensing revenue received by many developing states. Most importantly, we argue that tools exist today to manage for, reduce or eliminate most of the negative impacts of dFADs (e.g., bans on discards, limits on active dFADs, biodegradable non-entangling constructions, time-area deployment closures, recovery programs, and full data transparency, among others). Management decisions based on sound scientific reasoning are needed to address the legitimate concerns surrounding dFAD use and ensure the sustainability of both pelagic and coastal ecosystems and tropical tuna PS fisheries.     

Towards a sustainable fisheries policy in Europe

The reform of the European Common Fisheries Policy (CFP) in 2013 decides whether the European fisheries can be put on a sustainable course in the next 10 years. The CFP reform must halt overexploitation of fish resources and stop harm to the marine environment by fishing activities. The European Commission published a reform proposal just recently. This proposal is already an important first step in the right direction, but is under threat of being watered down by the Fisheries Council. Necessary improvements of the current CFP include among others a binding definition of a sustainable stock management, a discard ban for all fish species, transferable fishing concessions and a cessation of all aid for building new vessels. These modifications pave the way for placing micromanagement in the hands of regions and fisheries so as to foster self‐responsibility among fishers and give greater consideration to regional circumstances.     

Non-commercial invertebrate discards in an experimental trammel net fishery

Abstract  Non-commercial invertebrate discards in an experimental trammel net fishery were studied in relation to selectivity of the gear, depth, soak time and season. Forty experimental fishing trials were carried out over a 1-year period with six combinations of small mesh (100, 120 and 140 mm) inner and large mesh (600 and 800 mm) outer panels. On average, 43.8 ± 12.2 (SD) (individuals 1000 m⁻¹ of net) of non-commercial invertebrates were discarded, accounting for 48% and 65% of the total catch and total discards by numbers, respectively. Within non-commercial invertebrates discards, the six most abundant species by number were Phallusia mammillata (Cuvier) (27.5%), Cymbium olla (L.) (13.0%), Sphaerechinus granularis (Lamarck) (11.3%), Paracentrotus lividus (Lamarck) (10.9%), Astropartus mediterraneus (Risso) (8.2%) and Astropecten aranciacus (L.) (8.1%); Echinoderms (43.1%) particularly important. The highest and lowest discard ratios were found in autumn and winter, respectively. Discards generally decreased with depth, varied considerably in relation to soak time and were not related to mesh size combinations. Trammel nets seem to be the most important gear in terms of ecological impacts on benthic invertebrates compared with other coastal fishing gears and at the depths studied (15–60 m).     

Ending overfishing while catching more fish

The world's seas and oceans are a vital source of animal protein from fishing and a major contributor to global food security. It has been argued that global wild‐catch production has reached its limit, and there is concern that many species are overfished. Concerns are also mounting about the state of marine ecosystems and the ecological impacts of fishing on them, with increasing efforts to protect marine biodiversity. Fisheries appear to be at an impasse – demand for seafood is rising but so is concern about the impacts of fishing. However, through a simple analysis, we show that global exploitation rates are well below long‐term sustainable levels at a whole ecosystem level. The oceans can support considerably higher sustainable catch than currently harvested. Overfishing has happened but only to a small fraction of species as a result of intensive and selective fishing. Shifting fishing effort away from highly targeted stocks towards currently underutilized species would reduce pressure on overfished species, result in fewer adverse ecosystem effects of fishing and increase overall fisheries production. This shift requires significant changes to our views about seafood, particularly in the developed world. We suggest ways in which this paradigm shift could happen and the range of expertise that would be required to achieve higher global yields with less ecological impact.     

Feasibility of a single-species quota system for management of the Malaysian multispecies purse-seine fishery

Malaysian fisheries employ multiple measures to improve management; however, not all are well-suited to the multispecies fisheries. As part of a pilot project, an individual quota system was introduced for the purse-seine fishery off the East Coast of Peninsular Malaysia (ECPM), but no assessment of this particular measure nor the feasibly of its implementation has been confirmed. Therefore, this study analysed spatial and temporal patterns of purse-seine fishing, by collecting catch composition data per landing and its fishing ground within three period fishery surveys between August 2017 and September 2018 at six different landing sites. Similarity and cluster analysis examined species composition and diversity to determine the feasibility of implementing a single-species quota system in this multispecies fishery. Some overlapped of indices results and minor difference in catch composition were found due to changes in spatial and temporal fishing activities. However, no specific spatial or temporal patterns were discernible as structuring the fishing grounds used by purse-seiners. The absence of patterns, using the available data, might be attributable to huge species aggregations and widely distributed and homogenously mixed fish stocks. Thus, it is likely impractical to manage species individually in such a multispecies fishery.     

Fishing profiles of Danish seiners and bottom trawlers in relation to current EU management regulations

Danish seines and bottom trawls operate differently and have different catching processes. Both gears belong to the same legislative category in European fisheries, but different management strategies in other countries and criticism by fishers on grouping Danish seines and trawls together indicate disagreement on current gear classification. This study compared both gears in terms of their fishing characteristics and catches of commercial species based on 16 years of observer data. Danish seining is a specialised fishing method that targeted few species but with higher total catch rates than bottom trawlers. Bottom trawling is a more all‐purpose fishing method that targets a larger number of species, and bottom trawlers use larger engines than Danish seiners. A generalised additive mixed model indicated that catch rates of flatfish are generally higher for Danish seines, and catch rates of roundfish species are higher for trawlers. The results do not directly suggest a separation of the gears in terms of legislation as the quantities of fish below current minimum size were similar, but for example future survival studies may reach different conclusions. Additional factors were found to be important in determining catches of both gears.     

台湾海峡中南部海域光诱敷网渔业资源监测

本文根据2007—2008年台湾海峡中南部海域光诱敷网渔业监测调查资料,分析该渔场光诱敷网渔业利用状况及主要渔获种类资源动态。监测调查结果表明：光诱敷网作业生产汛期为6—10月,旺汛期6—8月;监测调查船年总渔获产量85～88t,主捕种类枪乌贼、鲐鱼、金色小沙丁鱼的渔获量分别约占总渔获量的35％、30％和20％。枪乌贼、鲐鱼、金色小沙丁鱼均属于生命周期短,生长快,资源补充量大的中上层种类,是多种作业的主要利用对象,目前枪乌贼、鲐鱼资源现状仍然保持相对良好,但在强大捕捞压力下,容易捕捞过度引起年间渔获量大幅度波动,因此对其资源应加以保护。     

阿曼苏丹渔场捕捞乌贼渔具改进的探讨

报道了山东圣海渔业集团公司渔轮赴阿曼苏丹渔场生产中有关渔具使用研究的情况 ,简述了渔场自然环境 ,目前应用的捕捞乌贼效果较好的网具主要参数 ,重点探讨了渔具改进的主要措施。     

A typology of fisheries management tools: using experience to catalyse greater success

Fisheries provide nutrition and livelihoods for coastal populations, but many fisheries are fully or over‐exploited and we lack an approach for analysing which factors affect management tool performance. We conducted a literature review of 390 studies to assess how fisheries characteristics affected management tool performance across both small‐scale and large‐scale fisheries. We defined success as increased or maintained abundance or biomass, reductions in fishing mortality or improvements in population status. Because the literature only covered a narrow set of biological factors, we also conducted an expert elicitation to create a typology of broader fishery characteristics, enabling conditions and design considerations that affect performance. The literature suggested that the most commonly used management tool in a region was often the most successful, although the scale of success varied. Management tools were more often deemed successful when used in combination, particularly pairings of tools that controlled fishing mortality or effort with spatial management. Examples of successful combinations were the use of catch limits with quotas and limited entry, and marine protected areas with effort restrictions. The most common factors associated with inadequate biological performance were ‘structural’ issues, including poor design or implementation. The expert‐derived typologies revealed strong local leadership, high community involvement and governance capacity as common factors of success across management tool categories (i.e. input, output and technical measures), but the degree of importance varied. Our results are designed to inform selection of appropriate management tools based on empirical data and experience to increase the likelihood of successful fisheries management.