Can catch share fisheries better track management targets?

Fisheries management based on catch shares – divisions of annual fleet‐wide quotas among individuals or groups – has been strongly supported for their economic benefits, but biological consequences have not been rigorously quantified. We used a global meta‐analysis of 345 stocks to assess whether fisheries under catch shares were more likely to track management targets set for sustainable harvest than fisheries managed only by fleet‐wide quota caps or effort controls. We examined three ratios: catch‐to‐quota, current exploitation rate to target exploitation rate and current biomass to target biomass. For each, we calculated the mean response, variation around the target and the frequency of undesirable outcomes with respect to these targets. Regional effects were stronger than any other explanatory variable we examined. After accounting for region, we found the effects of catch shares primarily on catch‐to‐quota ratios: these ratios were less variable over time than in other fisheries. Over‐exploitation occurred in only 9% of stocks under catch shares compared to 13% of stocks under fleet‐wide quota caps. Additionally, over‐exploitation occurred in 41% of stocks under effort controls, suggesting a substantial benefit of quota caps alone. In contrast, there was no evidence for a response in the biomass of exploited populations because of either fleet‐wide quota caps or individual catch shares. Thus, for many fisheries, management controls improve under catch shares in terms of reduced variation in catch around quota targets, but ecological benefits in terms of increased biomass may not be realized by catch shares alone.     

Wealth and welfare? Can fisheries management succeed in achieving multiple objectives? A case study of Lake Victoria,East Africa

Fisheries policies often pursue multiple objectives, which may, in some instances, be in conflict or competition with each other. It may not be possible, for example, to create or maintain employment and generate increasing volumes of revenue for government whilst also sustaining stocks and biodiversity. Two approaches to fisheries management, one focused on capturing wealth and limiting access and the other on maintaining access for employment and providing community development and welfare, present contrasting policy advice, with different points of emphases and objectives. This article examines the case of Lake Victoria, where the three main commercial fisheries are seen to contribute to different objectives for the lake's fisheries. Insights from the debate between wealth‐based and welfare‐based approaches to fisheries management provide a framework for the analysis of fisheries policy and practice on the lake. From the analysis, it is concluded that whilst there is much rhetoric in support of a wealth‐based approach, this has not been followed through in implementation, reflecting the lack of political support for new taxation and limiting access. The welfare functions of the fisheries are significant, but could be substantially strengthened through greater investment in the provision of services to fisheries communities. The approaches are not mutually exclusive, but pursuing wealth‐based management must support livelihoods, employment and development, as well as fisheries management objectives. Without the incorporation of welfare objectives, fisheries policies will not be politically accepted or fully implemented, suggesting the need for a balance between wealth and welfare objectives and measures.     

Which design elements of individual quota fisheries help to achieve management objectives?

Individual quota (IQ) management systems in commercial marine fisheries are highly diverse, differing in the security, durability and exclusivity of the harvesting privilege and the transferability of quota units. This diversity in the degree of harvest rights may influence the effectiveness of IQ fisheries to meet management objectives. We conducted a global meta‐analysis of 167 stocks managed under IQs to test whether the strength of harvest rights impacts the conservation status of stocks in terms of catch, exploitation rate and biomass relative to management targets. We used non‐parametric methods to assess non‐linear relationships and linear regression models to explicitly consider interactions among predictors. Most IQ fisheries consistently met fleet‐wide quota limits (94% of stocks had recent catches below or within 10% of quotas), but only 2/3 of IQ fisheries adhered to sustainable management targets for biomass and exploitation rate (68% of stocks had exploitation rates below or within 10% of targets and 63% of stocks had biomass above or within 10% of biomass targets). Strikingly, when exclusivity of the harvesting privilege was low, exploitation rates depended on whether IQ implementation was industry‐driven (exploitation below targets) or government‐mandated (exploitation above targets). At high levels of exclusivity, exploitation rates converged to just below management targets. Transferability of quota units was associated with stock biomass closer to and slightly above target levels than stocks with non‐transferable quota. However, regional differences had the strongest effect on biomass, suggesting that other management or biological attributes of regional fishery systems have greater influence on marine populations.     

Resilient recreational fisheries or prone to collapse? A decade of research on the science and management of recreational fisheries

Are recreational fisheries resilient to harvest or prone to collapse? This paper reviews research published since that question was posed by Post et al. (2002, Fisheries 27 , 6–17). A number of patterns and processes have been identified that suggest understanding the risk of collapse requires knowledge of the fishing effort response, degree of depensation in the fishery and the life history of the harvested species. Processes involving the behaviour of fish, behaviour of anglers and management responses to declining quality can all impact the degree of resilience of recreational fisheries and their risk of collapse. The spatial context of an individual fishery can be important as they are often embedded in lake districts and joined by mobile anglers so their local dynamics are not independent from other fisheries. Typical regulations that restrict the behaviour of individual anglers in open‐access fisheries can provide some resilience but cannot prevent collapse if the fishing effort is too high. Many uncertainties remain related to the occurrence and intensity of the key processes and therefore adopting an adaptive experimental management approach might be the most useful approach to minimise the risk of collapse in recreational fisheries.     

Regional fisheries management organizations and the new biodiversity agreement: Challenge or opportunity?

In 2018, the international community began formal intergovernmental negotiations over a new legally binding instrument for the protection of marine biodiversity of areas beyond national jurisdiction. Protecting marine biodiversity is imperative for a sustainable future, and all the different organizations and agreements will have to work together to achieve this common goal. One of the first key principles to be agreed was to “not undermine” the existing legal instruments or mandates of regional and sectoral marine governance organizations. While fisheries are not being discussed during the negotiations, a marine biodiversity agreement is likely to still impact regional fisheries management organizations (RFMOs), due to overlapping areas of interest. This article aims to firstly, assess the potential constraints posed by the commitment to “not undermine”; secondly, consider how aspects of the biodiversity agreement, such as area‐based management and environmental impact assessments, might enhance RFMOs; and thirdly, suggest meaningful ways to ensure cooperation between RFMOs and the marine biodiversity agreement.     

Is fisheries governance possible?

Are there limits to the governability of a fishery? The establishment of a 200 nautical mile economic zone in Norway in 1977 made it possible to change from an open‐access regime to a more closed one. In this process, the former self‐regulating Norwegian fishing industry, to a large extent, accepted and adapted an explicit, hierarchical form of state‐run governance. However, the process of change did not stop there. Since the turn of the millennium, we have seen the creation of a cybernetically organized fishing industry, where control, regulation and governance have become re‐embedded in the industry. This article explores this radical new development and perspective on fisheries governance and governability based on lessons learned from technological and organizational changes in the Norwegian fishing industry.     

Experimental harvesting of Mytilus galloprovincialis: Can an alien mussel support a small-scale fishery?

In an effort to stimulate new fisheries and address historic imbalances in access to fishing rights, there has been a recent focus on the development of small-scale fisheries in South Africa. To assess the biological viability of a fishery for the alien mussel Mytilus galloprovincialis, an experimental fishery operated by two impoverished coastal communities was initiated. Harvesting took place on a rotational basis at three sites, nested within four locations. At each of these 12 sites, 5 treatments were undertaken to span a spectrum of harvesting intensities (F = 0, 0.3, 0.6, 0.9 and a once-off total removal). A dynamic biomass-based fisheries model was developed to predict changes in exploited populations over time. Monthly maximum sustainable yield (MSY) estimates peaked at 1560 kg per 100 m of shore in March–April and September–October, but dropped by two orders of magnitude to 15 kg per 100 m of shore during the remainder of the year. The two peaks in MSY corresponded to the peak spawning periods of M. galloprovincialis along the South African west coast. Consequently, harvesting will only be viable if focused within two seasons spanning the peaks in MSY. Under these conditions, a range of harvesting intensities between F = 0.1 and 0.3 would permit long-term biological sustainability of a fishery. If implemented, this would represent the first instance of a marine invasive species being utilised to achieve socio-economic goals in South Africa.     

What makes some fisheries references highly cited?

We identify the 199 most‐cited fisheries references up to July 2014, topped by Nelson's Fishes of the World. Few book chapters, databases or reports were included, but review articles and field guides were over‐represented. Publishing in Science, Nature or Proceedings of the National Academy of Sciences USA is associated with a 34‐fold increase in the probability of an article being highly cited, but many highly cited references were also published in journals with impact factors under eight. Proportional contributions to references, taking into account number of authors, author order and other key factors, revealed Bill Ricker and John Roland Brett as the greatest individual contributors, and the US, Canada and the UK as greatest country contributors, with Canada significantly over‐represented. Female representation on the list was historically low before increasing to 21% in the 1990s, and reflected gender changes in the field of fisheries. When compared to >2000 control papers published in the same journal and year, highly cited fisheries papers were significantly longer (20.4 vs. 9.8 pages) and had more authors (5.8 vs. 4.3), references (118 vs. 51), tables and total illustrations; these differences were greater when high‐profile general journals were excluded, but lower when calculated on a per‐page basis. References with more than six authors jumped from 0 to 27% in 2000, coinciding with a rapid uptake of email among fisheries scientists. Overall, we find no shortcut to publishing highly cited references: they require substantial time, effort and knowledge invested in new hypotheses, textbooks, field guides, new discoveries, broad meta‐analyses, new methods and reviews.     

Mismanagement of fisheries: Policy or science?

Several gadoids stocks in the Northeast Atlantic are currently considered as severely overexploited. A fast spreading paradigm is that conventional single-species fisheries management has failed and new approaches are needed. A crucial element of this “novel way of thinking” is the cheered move from conventional single-species management to ‘ecosystem-based management’ in order to assure sustainability in the long term. Here we showed that although conducted within a deterministic single stock modelling framework, and without invoking the ecosystem approach, scientific advice if applied, mirrors in stocks being in relative healthy state. We argue that managers and politicians have had the necessary scientific instruments for managing stocks and avoid stock collapses, but they failed as they tried to minimize the impact of policy on those who are most affected (i.e. the fishing industry) in a short-term perspective. Thus, our results strengthen the hypothesis that it is the practise of ignoring the scientific advice more than the advice itself that is to be blamed for the waste of former large marine resources. What we urgently need for securing marine ecosystems is not more data but immediate actions.     

Using fisheries-independent survey data to reinforce China’s data-limited fisheries management: Management strategy evaluation of survey-based management procedures

Fisheries-independent survey data are vital to stock assessment and management because they provide reliable information on stock status. Although survey data have been increasingly recognised for their contributions to fisheries management, they have often not been adequately used to provide quantitative management recommendations for China's fisheries that are subject to limited data. In the present study, a framework was proposed to integrate two types of survey-based management procedures (MPs) into China's fisheries management: the slope-based MP and the target-based MP. Specifically, the former generates fishing effort limits based on the trend in recent years’ abundance index, while the latter sets effort limits based on a static abundance index target. To test the performance of these MPs, management strategy evaluation was performed using a simulated fishery based on the small yellow croaker, Larimichthys polyactis (Bleeker) in Haizhou Bay, China. The sensitivity of MPs was investigated under different algorithm parameterisations and historical exploitation levels. Additionally, their robustness was evaluated in the face of survey uncertainty and changes in recruitment success. Both MPs could effectively improve the stock status compared with the status quo management when appropriately parameterised regardless of exploitation history. The target-based MP was more robust to survey uncertainty than the slope-based MP. Non-stationary changes in recruitment success strongly impaired the management effects, while using recruitment-specific instead of the age-aggregated abundance index could slightly enhance their performance. This work indicates that survey-based MPs can address the current challenges in China's fisheries management and reinforce the status quo management practice with limited data and highlights the potential risks.     

Can management practices in rice fields contribute to amphibian conservation in southern Brazilian wetlands?

• 1. Rice field expansion is one of the activities associated with the disappearance of 90% of the wetlands in southern Brazil. Worldwide, rice agriculture has been recognized as having considerable potential value for many aquatic species. Nevertheless, management practices in such systems must be ameliorated and better investigated.
• 2. This study evaluated the potential role of rice fields as refugia for amphibians, and whether different hydrologic management practices after rice cultivation could contribute to wetland amphibian conservation in southern Brazil.
• 3. Six collections were made in six rice fields with different management practices after cultivation (three dry and three flooded) and three natural wetlands. The amphibians were sampled through six random 15‐min visual transects per collection in each rice field and the natural wetlands.
• 4. In total, 2139 anuran individuals were observed in rice fields (798) and Reserva Lake (1341), comprising 12 anuran species distributed among five anuran families. Anuran richness and abundance varied over the rice cultivating cycle, and they were higher in the growing phases than in the fallow phases. The mean anuran richness and abundance was higher in Reserva Lake than in flooded and dry rice fields.
• 5. The different management practices adopted after the harvesting period (presence or lack of surface water) did not influence the anuran richness and abundance. It did, however, influence species composition.
• 6. The difference in species composition between the management practices adopted is an interesting result in terms of biodiversity conservation. Rice producers could maintain part of their agricultural land flooded during the fallow phase as a strategy to preserve a higher diversity of anurans. These results should be taken into consideration in wetland conservation plans in southern Brazil; however, the percentage of each agricultural land that should be kept flooded should be decided by Brazilian agricultural and conservation policies. Such a strategy would reconcile agricultural/economic needs with the conservation of biodiversity in southern Brazil, where more than 90% of wetland systems have already been lost. Copyright © 2009 John Wiley & Sons, Ltd.

     

Does trade openness reduce a domestic fisheries catch?

Although trade liberalization may increase a country’s welfare, its specific effect on a country’s fishing industry has not been well studied. By decomposing the effect of international trade into four parts, i.e., scale-technique effects (ST), the indirect trade-induced composition effect (IC), the indirect effect of trade intensity through income (ITC), and the direct effect of trade intensity (DTC), this study empirically investigates the effect of trade openness on country-level fisheries production. To take into account the endogeneity of trade openness and income, we adopt the instrumental variable approach. We find that a rise in trade openness reduces fisheries catch on average. In particular, the long-run effect is large. This result implies that future production is affected by current overfishing through stock dynamics. Our decomposed elasticities indicate that the ST and ITC dominate in the trade elasticity of fisheries catch. While ST implies that overfishing would be affected by trade, ITC may either establish an “overfishing haven”, similar to a “pollution haven” in the environmental literature, or production shift of fisheries to countries with lax regulation to pass stringent regulation, which is more likely to occur in high-income countries.     

Will philopatry in sea bass, Dicentrarchus labrax, facilitate the use of catch-restricted areas for management of recreational fisheries?

Many adult sea bass (>40 cm total length) tagged between May and October around the coasts of England and Wales have been recaptured close to their respective tagging locations in successive years. Analysis of mark and recapture data sets, for the late 1970s and early 1980s and in 2000–2006, show that some 55% of all recaptures were within 16 km of their original release position. This suggests that mortality rates of adult bass in local populations could be reduced by around 50% if a number of carefully selected areas were designated as catch and release only for bass, thus providing a management option with which more and bigger sea bass will be available to recreational sea anglers.     

Do recreational fisheries metrics vary on differently sized fishing grounds?

This study aimed to assess the relationship between basic metrics in recreational fishing and the size of the fishing ground. Data were obtained from individual angling logbooks collected by the Czech Fishing Union over 12 years on 212 fishing grounds located in the regions of Prague and Central Bohemia in the Czech Republic. Small fishing grounds had the highest catch, yield, numbers of fishing visits and numbers of angling guard controls per hectare. Medium‐sized fishing grounds had the highest catch, yield, and numbers of both fishing visits and angling guard controls per fishing ground. Anglers returned to medium‐sized fishing grounds most frequently. The percentage of anglers who caught and took home at least one fish decreased with increasing size of the fishing ground. In conclusion, basic metrics in recreational fishing are related to the size of the fishing ground, which thus plays an important role in fisheries management.     

Evolution of marine fisheries management in China from 1949 to 2019: How did China get here and where does China go next?

China is the world’s biggest fishing nation and a major player in the global seafood trade. Its fisheries development can decisively influence the global seafood trade, food security and marine conservation. In recent years, significant changes have taken place in China’s fisheries management priorities, policies and regulations. In this paper, we review the evolving fisheries management practices in China to delineate changes in the management policies, methods and their performances from 1949 to 2019. We determined that the following issues impede the development, implementation and enforcement of fisheries policies and regulations, namely the large size of the fishing fleet, large and poorly organized fisheries population, the “hidden” fishing capacity, uniform management approaches that sometimes fail to account for local conditions, lack of clearly defined and allocated fishing rights, limited data quality and availability, insufficient fisheries monitoring programmes, absence of a robust scientific input framework and insufficient stakeholder involvement. Combining those problems with China’s current management initiatives, we propose recommendations for China’s future fisheries reforms. We hope this paper can inform China’s marine fisheries policies and provide valuable references for further researches related to China’s sustainable fisheries management.     

Reservoir fish assemblage structure across an aquatic ecotone: Can river-reservoir interfaces provide conservation and management opportunities?

River-reservoir interfaces have been described as aquatic ecotones and contain strong environmental gradients of depth, turbidity and trophic resource abundance. These transitional habitats have traditionally been excluded by riverine and reservoir management schemes despite their prevalence in modern riverscapes. By systematically sampling shoreline habitats along a river-reservoir interface gradient from riverine to lacustrine zones with trammel nets in 2018–2019, strong patterns were identified in total species captured and individuals captured in the San Juan River-Lake Powell inflow, USA. Changes in assemblage structure were driven mainly by increases in relative abundance of benthic omnivores towards the riverine zone, including imperiled razorback sucker, Xyrauchen texanus (Abbott), but also by increases in predatory species, such as striped bass, Morone saxatilis (Walbaum). Inter-annual variation in species distributions along the river-reservoir interface gradient was likely influenced by variation in reservoir water level that differed by nearly 12 m between years. River-reservoir interfaces provide high-quality feeding and potentially spawning areas for both benthic omnivores and piscivores, and these areas should be considered in management and conservation efforts for species using these habitats.     

Biomass removal by dolphins and fisheries in a Mediterranean Sea coastal area: do dolphins have an ecological impact on fisheries?

• 1. Dolphins are often claimed to compete with fisheries, including through removal of substantial biomass. To calculate the biomass removed by fisheries and the degree of resource overlap with dolphins in a coastal area of Greece, estimates of dolphin abundance based on photographic capture–recapture were combined with an assessment of fishing effort and catch.
• 2. The estimated total biomass consumed annually by local dolphin populations – 15 short‐beaked common dolphins and 42 common bottlenose dolphins – was 15.5 and 89.8 tonnes, respectively. The total biomass removed by the local fishing fleet (307 fishing boats) was 3469.2 tonnes, i.e. about 33 times greater than that removed by dolphins.
• 3. Dolphins removed 2.9% of the total biomass, fisheries 97.1%. Nine purse seiners (representing only 3% of the active fishing fleet) were responsible for 31.9% of biomass removal. Similarity of biomass composition between dolphins and fisheries was expressed by a Pianka index of 0.46 for common dolphins and 0.66 for bottlenose dolphins.
• 4. Overlap differed according to fishing gear. Common dolphin overlap was higher with purse seiners (0.82), and lower with beach seiners (0.31), bottom trawlers (0.11) and trammel boats (0.06). There was virtually no overlap with longliners (0.02). Bottlenose dolphin overlap was higher with trammel boats (0.89) and bottom trawlers (0.75), and lower with longliners (0.38), purse seiners (0.24) and beach seiners (0.18). There was minimal overlap (0.12) between the two dolphin species.
• 5. This study suggests that ecological interactions between dolphins and fisheries in this coastal area have minor effects on fisheries. Conversely, prey depletion resulting from overfishing can negatively affect dolphins. Fisheries management measures consistent with national and EU legislation are proposed to ensure sustainability and to protect marine biodiversity. Copyright © 2010 John Wiley & Sons, Ltd.

     

Finnish lake fisheries and conservation of biodiversity: coexistence or conflict?

The conservation of biodiversity in aquatic habitats has become an increasingly important challenge in the management of water resources. In addition to the complexity of the lake fishery and the management structure, the popularity of gill net fishing, in particular, has brought problems when re-establishing populations of Arctic charr, Salvelinus alpinus (L.), collecting genetically sustainable numbers of spawners of the land-locked salmon, Salmo salar m. sebago (Girard), and increasing the population of the Saimaa ringed seal, Phoca hispida saimensis (Nordq.) to a sustainable level in the Vuoksi watercourse, south-east Finland. The attitudes towards protection among the users and other interested parties vary. In order to enhance the coexistence of the lake fishery and endangered species over large water areas, improved institutional linkages are needed among the local, regional and governmental levels of the fragmented decision-making regime. Environmental interests should also be integrated into the communication structure.     

Can fish really feel pain?

We review studies claiming that fish feel pain and find deficiencies in the methods used for pain identification, particularly for distinguishing unconscious detection of injurious stimuli (nociception) from conscious pain. Results were also frequently misinterpreted and not replicable, so claims that fish feel pain remain unsubstantiated. Comparable problems exist in studies of invertebrates. In contrast, an extensive literature involving surgeries with fishes shows normal feeding and activity immediately or soon after surgery. C fiber nociceptors, the most prevalent type in mammals and responsible for excruciating pain in humans, are rare in teleosts and absent in elasmobranchs studied to date. A‐delta nociceptors, not yet found in elasmobranchs, but relatively common in teleosts, likely serve rapid, less noxious injury signaling, triggering escape and avoidance responses. Clearly, fishes have survived well without the full range of nociception typical of humans or other mammals, a circumstance according well with the absence of the specialized cortical regions necessary for pain in humans. We evaluate recent claims for consciousness in fishes, but find these claims lack adequate supporting evidence, neurological feasibility, or the likelihood that consciousness would be adaptive. Even if fishes were conscious, it is unwarranted to assume that they possess a human‐like capacity for pain. Overall, the behavioral and neurobiological evidence reviewed shows fish responses to nociceptive stimuli are limited and fishes are unlikely to experience pain.     

DNA‐analysis to monitor fisheries and aquaculture: Too costly?

Evidence from DNA‐analysis is commonplace in human criminal investigations, and while it is increasingly being used in wildlife crime, to date, its application to control and enforcement activities in fisheries and aquaculture has only been sporadic. Contemporary DNA‐analysis tools are capable of addressing a broad range of compliance issues, species identification, mislabelling of fish products, determining the origin of catches and the farm of origin of aquaculture escapees. Such applications have the potential to ensure traceability along the fish product supply chain and to combat consumer fraud and Illegal, Unreported and Unregulated fishing. Nevertheless, DNA‐analysis is not yet used routinely in investigations into compliance with fisheries and aquaculture legislation. One potential reason for this is that DNA‐analysis techniques may have been regarded as too expensive. However, costs have plummeted over the past decade prompting us to objectively assess whether the costs associated with routine use of DNA‐analysis techniques for fisheries and aquaculture control and enforcement activities do constitute an impediment. Based on a number of recent fisheries and aquaculture compliance investigations that incorporated DNA‐analysis, our results indicate that the use of genetic analysis was justified and worthwhile in all cases examined. We therefore conclude that the costs associated with DNA‐analysis do not represent a barrier to the routine adoption of DNA‐analysis techniques in fisheries and aquaculture compliance investigations. Thus, control and enforcement agencies should be encouraged to use such techniques routinely.