Shark interactions in pelagic longline fisheries

Substantial ecological, economic and social problems result from shark interactions in pelagic longline fisheries. Improved understanding of industry attitudes and practices towards shark interactions assists with managing these problems. Information on fisher knowledge and new strategies for shark avoidance may benefit sharks and fishers. A study of 12 pelagic longline fisheries from eight countries shows that incentives to avoid sharks vary along a continuum, based on whether sharks represent an economic disadvantage or advantage. Shark avoidance practices are limited, including avoiding certain areas, moving when shark interaction rates are high, using fish instead of squid for bait and deeper setting. Some conventionally employed fishing gear and methods used to target non-shark species contribute to shark avoidance. Shark repellents hold promise; more research and development is needed. Development of specifically designed equipment to discard sharks could improve shark post release survival prospects, reduce gear loss and improve crew safety. With expanding exploitation of sharks for fins and meat, improved data collection, monitoring and precautionary shark management measures are needed to ensure that shark fishing mortality levels are sustainable.     

International fisheries agreement: Review of the International Commission for the Conservation of Atlantic Tunas: Case study—Shark management

To properly manage world fisheries, especially highly migratory species, there are numerous treaties that have been implemented by specialized international fishery commissions. One of the oldest organizations is the International Commission for the Conservation of Atlantic Tunas (ICCAT). The main focus of this review was to summarize the history, roles and responsibilities of ICCAT, and to evaluate ICCAT's management of sharks in general and specifically for shortfin mako (Isurus oxyrinchus) shark. This review found that the Convention was established 40 years ago, but it was not until 2004 that the commission conducted its first population assessment on pelagic sharks.     

Interactions between whale sharks,Rhincodon typus Smith, 1928 (Orectolobiformes,Rhincodontidae), and Brazilian fisheries: The need for effective conservation measures

This study reports three interaction events between the whale shark (Rhincodon typus) and fisheries in Brazilian waters. Two events were described as incidental captures in a gillnet fishery on the northern coast of Rio de Janeiro State, in southeastern Brazil. The last event took place at the Royal Charlotte Oceanic Bank (RCOB), in the southern region of Bahia State, where five fishermen filmed their interaction with a juvenile specimen. For one of the incidental captures, the fish was landed and consumed by locals, and for the other, the shark was released. In the RCOB, the fishermen touched the whale shark with their hands, wooden sticks and even rode on it. In addition, 74 interviews were conducted with fishermen from Bahia about sightings and possible interactions with R. typus. According to statements made by the fishermen, although not frequent, the conduct reported for the RCOB occasionally takes place in the region. Evaluating information of this nature is important to support government plans that regulate fishing activities in order to reduce incidental captures and the harassment of whale sharks. Encouraging the participation of fishermen in a collaborative monitoring program for R. typus may be a good way to better understand the threats to the species at a reduced cost, particularly for developing countries, such as Brazil.     

Analysis of bycatch in the South African midwater trawl fishery for horse mackerel Trachurus capensis based on observer data

The South African midwater trawl fishery targets adult horse mackerel Trachurus capensis. The bulk of the catch is taken by a single freezer-trawler, the biggest fishing vessel operating in South African waters. As fishing takes place off the south coast in ecologically sensitive areas, there are concerns about the potential impacts of this fishing operation on non-target species. Fishing behaviour and bycatch of this fishery from 2004 to 2014 were investigated by analysing observer records with regard to catch composition, volume and temporal and spatial patterns. The midwater trawl fishery was estimated to have caught 25 415 tonnes annually, with a bycatch of 6.9% of the total catch, by weight. There are species overlaps with various fisheries, namely the demersal trawl, small-pelagic, line, shark longline and squid fisheries, yet the total bycatch estimates from this fishery are generally small relative to catches taken in the target fisheries. Bycatch species with the highest average annual catches were chub mackerel Scomber japonicus, redeye roundherring Etrumeus whiteheadi, ribbonfish Lepidopus caudatus and hake Merluccius spp. Large-fauna bycatch species included sunfish Mola mola as well as a number of CITES II- and IUCN-listed species, such as Cape fur seal Arctocephalus pusillus, dusky shark Carcharhinus obscurus, smooth hammerhead shark Sphyrna zygaena and thresher sharks Alopias spp. The 97.9% observer coverage is high and the 6.9% bycatch rate low compared to other South African fisheries; however, due to the large size of the individual hauls (average of 46.3 t), the average sampling rate of 1.56% is low. Our analyses suggest that bycatch in the South African midwater trawl fishery has been lower than in other South African fisheries and similar fisheries elsewhere, but due to the combination of high catch volumes and low sampling rates, estimation errors for rare species are high and there is a substantial risk of incidental unmonitored bycatch of rare large fauna and aggregations of small fauna. This could be mitigated by spatio-temporal management of this fishery, to avoid fishing in high-risk areas, and the introduction of an electronic monitoring programme.     

The elasmobranch fisheries of the Azores

In the Northeast Atlantic, elasmobranchs are a common bycatch in many fisheries, including demersal trawls, longlines, or gillnets and many countries do not have regulations or any control over the amount taken. In the Mid Atlantic, the Azores EEZ (Exclusive Economic Zone), small-scale fishing operations, artisanal and hook-and-line fishing methods are responsible for part of local total landed elasmobranch biomass, although some species are specifically focused and severely harvested by international large-scale fleets. This work provides a review and analysis of the commercial elasmobranch fisheries in the Azores EEZ, and its evolution over the last two decades, highlighting management priorities, taking into account the Northeast Atlantic elasmobranch fisheries status. In the Mid-Atlantic, elasmobranch fisheries mainly target 4 species, that are usually landed as bycatch: the tope shark (Galeorhinus galeus) and the thornback ray (Raja clavata), captured mainly by local demersal artisanal fisheries, the blue shark (Prionace glauca) and the shortfin mako shark (Isurus oxyrinchus) captured by a more industrialised fleet, including those from foreign nations. Considering elasmobranchs life history traits and fishery history, caution is advised in the development of a management strategy focusing on these species, considering the Northeast Atlantic context and regional, local and national interests.     

Attitudes and perceptions influence recreational angler support for shark conservation and fisheries sustainability

Despite the perilous status of many shark populations, rallying support for their conservation has been challenging, due in part to both long held negative perceptions and desire for shark fisheries. Recreational anglers are often advocates of conservation and can act as valuable partners with resource managers in developing fisheries management and conservation strategies. However, understanding their attitudes and perceptions, particularly towards resource status and management, is essential to developing successful management strategies and predicting outcomes. As a case study for assessing the complex challenges of sustainable shark fisheries, Florida recreational anglers were surveyed to understand how attitudes and perceptions influenced their willingness to donate for shark 1) conservation and protection or 2) fisheries sustainability. Overall, recreational angler willingness to donate was 25.5%, but attitudes and perceptions helped explain dramatic divides. For instance, willingness to donate was only 6% among the subset of anglers that perceived a growing large coastal shark population as a threat to recreational fishing opportunities. Highest support for shark conservation was shown by anglers who value seeing sharks in the wild (41.4%), and even more so among individuals who occasionally target sharks while fishing recreationally (65.8%). Pervasive among anglers unwilling to donate was a perception that shark populations were increasing, and thus not in need of further protection. These findings illustrate attitudes and perceptions that challenge shark conservation and fisheries management, as well as the critical importance of engaging anglers when developing strategies that rely on the recreational angling community for support.     

A United States shark fin ban would undermine sustainable shark fisheries

A proposed nationwide ban on the sale of shark fins within the United States would undermine sustainable shark fisheries, would have little effect on global shark mortality, and would perpetuate the misconception that the shark fin trade is the only threat facing sharks. Instead, placing a priority on policies focusing on sustainable shark fisheries management is preferred for meeting the goals of shark conservation.     

The case for an international commission for the conservation and management of sharks (ICCMS)

The current rate of shark global exploitation and mortality is arguably so high under current management regimes that unless a renewed initiative is undertaken some species of shark will become effectively extinct. Current efforts to sustainably manage shark mortality are driven primarily by domestic laws in a few countries, big international non-governmental organizations (BINGOs) promoting environmental laws in the countries or regions where they exist, a handful of regional fisheries management organizations (e.g., IATTC and ICCAT), and inter-governmental organizations such as CITES. The absence of enforcement capability is often argued as the critical component in the failure to protect sharks from overexploitation. The remedy advanced here goes far beyond the need for stepped up enforcement, and calls for the creation of an entirely new international management regime, the International Commission for the Conservation and Management of Sharks (ICCMS). Such an agency could learn from the experiences of management bodies tasked with conservation of species biologically similar to sharks, such as the International Whaling Commission (IWC), to improve its efficacy. Critics have identified many organizational flaws that reduced the IWC’s effectiveness during its earliest years. Some of those flaws are examined here and remedies are suggested that an ICCMS could use to create a more effective management regime. The life histories of elasmobranches and large whales are compared to illustrate their similarities as a biological foundation for the selection of the IWC as a model.     

Keeping the lead: How to strengthen shark conservation and management policies in Canada

Internationally, shark conservation is now being recognized as a major environmental challenge, but management efforts to halt the overexploitation of sharks have lagged behind. This review examines the state of knowledge for shark species in Canadian waters and analyzes the role of existing management and legislation in ensuring shark conservation. Despite Canada's early leadership, the present management framework reveals major shortcomings with regard to legal protection, bycatch and finning regulations. These problems are not unique to Canada but illustrate broader issues pertaining to the global management of endangered fish species. To strengthen the conservation and management of sharks, this paper recommends a set of key policies and management priorities, which exemplify proper precautionary management of endangered shark species in Canada and could serve as a blueprint for improving conservation efforts internationally. A structured approach for grading progress in shark conservation efforts against best practices is also presented and could be used as a goalpost elsewhere.     

Standards for the effective management of fisheries bycatch

Mitigating the environmental impact of commercial fishing, by avoiding, minimizing and compensating for adverse effects, is core business for fisheries management authorities globally. The complex interplay of ecological, economic, and social considerations has often resulted in bycatch management being reactive, confrontational and costly. In many cases it has been difficult to demonstrate success and to establish whether bycatch management has been efficient or effective. This article proposes standards for bycatch management following reviews of literature, international agreements and Australian domestic fishery management policies, and consideration by many technical experts and several stakeholder representatives. The standards have been developed using Australian Commonwealth fisheries – and the international fisheries agreements to which Australia is party – as a baseline, but should be applicable to both domestic and regional/international governance systems. The proposed standards involve quantifying fisheries bycatch, agreeing on operational objectives, assessing the effects of fishing on bycatch populations, establishing the cost-effectiveness of mitigation measures, and evaluating performance. The standards encourage domestic management measures that are consistent with the guidance and requirements of international agreements and regional fisheries management organisations. The importance of engaging stakeholders throughout the process is recognised. The standards provide a framework for measuring performance and a checklist of actions for managing bycatch at a fishery level. They have the potential to facilitate the development of more strategic and effective approaches to bycatch management, with defined goals, monitoring systems, and adaptive decision-making. This review of past bycatch management, including the application of the proposed standards to the mitigation of shark bycatch in an Australian longline fishery, demonstrates that the proposed standards are operationally feasible but that they have not always been applied. Specifically, monitoring the performance of bycatch management measures has not always followed their implementation.     

Transboundary fisheries management in the Amazon: Assessing current policies for the management of the ornamental silver arawana (Osteoglossum bicirrhosum)

The management and governance of shared stocks have long been identified as a challenge to achieve long-term sustainability in fisheries. This is the situation of fisheries in the Amazon basin, a region shared by nine countries. This paper provides an overview of the social-ecological outcomes and management implications of sharing fish stocks among countries with different public policies, taking the valuable Amazonian ornamental silver arawana (Osteoglossum bicirrhosum) trade as a case study. Specifically, it (i) presents and discusses the policies of Colombia, Peru and Brazil for the silver arawana fishery, and how these are conducive for the successful management of this shared transboundary fishery; and (ii) analyzes the market for the ornamental silver arawana and how it affects the ability to sustainably manage the fishery. The interplay between the multiple environmental, economic and social dimensions involved in the ornamental silver arawana fishery affects the sustainability of this species even in Brazil, where this fishing is forbidden but still illegally caught by Colombians and Peruvians. Among the factors that make fisheries policies inefficient in this region are: (i) incongruent policies between the countries and institutions with low organizational capacity to accomplish the established policies; (ii) environmental heterogeneity of Amazonian aquatic systems, which requires local and adaptive measures; and (iii) complex socio-economic relationships in the live-fish trade business. Legally binding efforts to reduce problems derived from shared fish stocks are an urgent need and should be addressed by the multilateral organizations created for the Amazonian sustainable development.     

Review of shark legislation in Canada as a conservation tool

Sharks are threatened from overfishing due to their life cycle biology, and unsustainably high catch rates to supply fins for shark fin soup. Canada, a leader in shark conservation uses numerous legislative tools to help conserve sharks. These tools include international treaty obligations under the Northeastern Atlantic Fisheries Organization [NAFO] and the International Commission for the Conservation of Atlantic Tuna [ICCAT], as well as national and provincial legislation including the Fisheries Act, Pacific and Atlantic Fisheries Regulations, and Coastal Fisheries Protection Act. Through the use of these legislative tools Canada has successfully banned shark finning in its waters, and implemented closed seasons, gear restrictions, and species restrictions to help manage shark populations. However, Canada still allows the sale of shark fin products locally, and allows the exportation of shark fins internationally. In order for Canada to maintain its leadership status Canada must increase legislative protection of sharks by following international best practices, and ban the sale and exportation of shark fin products. This would ensure that Canada does not play a role in global supply or demand of shark fins. Doing so would strengthen Canada's position as a leader in shark conservation, and improve the legislation currently used as a conservation tool.     

中西太平洋围网不同作业方式兼捕镰状真鲨渔获率和死亡率分析

我国在中西太平洋(Western and Central Pacific Ocean,WCPO)金枪鱼围网渔业作业的方式主要分为捕捞自由鱼群(free swimming school,FSC)和人工集鱼群(fish aggregation devices,FAD),镰状真鲨(Carcharhinus falciformis)是这两种作业方式中主要的兼捕鲨鱼。本研究根据2018—2019年我国围网渔业渔船在中西太平洋区域(15°S—15°N,140°E—180°E)共20个作业航次记录的渔捞日志,对FSC和FAD两种状态的捕捞作业下兼捕到的镰状真鲨渔获率、生存状态等进行比较分析,结果表明:(1) FAD作业相比FSC作业兼捕到的镰状真鲨分布范围更广,两种作业方式兼捕到的镰状真鲨单位捕捞努力量渔获(catch per unit effort,CPUE)主要分布区域均集中在基里巴斯和瑙鲁专属经济区;(2) FAD和FSC兼捕镰状真鲨CPUE出现较高月份均在5—9月,FAD兼捕镰状真鲨CPUE显著高于FSC (P 0.05);(3) FSC和FAD兼捕镰状真鲨的死亡率范围分别为0.00%～92.86%和20.26%～76.71%,经检验两种作业方式下镰状真鲨死亡率间无显著性差异(P 0.05)。研究结果有助于了解不同作业方式对鲨鱼兼捕的影响,以实现提高目标鱼种渔获率、降低鲨鱼兼捕率的目的。     

Fisheries development in northeastern Asia in conjunction with changes in climate and social systems

The status and prospects of fisheries in northeastern Asia are reviewed in conjunction with climate change and social issues. This region has the biggest yield, consumption, and international trade of fisheries products in the world. Due to increasing industrialization and greenhouse gas emissions, higher rates of warming have occurred. The impacts of climate change on fisheries could be detrimental because the main fishery products are small pelagic fish whose biomass fluctuations are sensitive to climate changes. Improvements in the economies of the nations in this region offset the demand for fish products in human diets, and employment in fisheries. It is recommended that fisheries management plans consider both changes in climate and in social systems. Stocks which migrate between national jurisdictions are in need of particular attention.     

Ecological risk assessment of the Marshall Islands longline tuna fishery

To support implementing an ecosystem approach to fisheries management, ecological risk assessment (ERA) methods have recently been developed for the continuum of data-deficient to data-rich fisheries. A semi-quantitative ERA was conducted for the Marshall Islands longline bigeye tuna (Thunnus obesus) fishery. The study used information from analyses of observer data, surveys of captains and crew and inventories of gear and equipment. Relative risks were evaluated through a consideration of phylogenetic uniqueness, risk of population extirpation, risk of species extinction and importance in ecosystem regulation. The fishery presents a highest relative risk to leatherback (Dermochelys coriacea), hawksbill (Eretmochelys imbricata), green (Chelonia mydas) and olive Ridley (Lepidochelys olivacea) sea turtle Regional Management Units that overlap with the fishery, in that order. The next highest relative risk is to affected stocks of oceanic whitetip (Carcharhinus longimanus), blue (Prionace glauca), and silky (Carcharhinus falciformis) sharks, in that sequence. Seabird bycatch is likely not problematic. There was inadequate information to assess risks to cetacean populations. Risks to stocks of market and non-market species of marine fishes with r-selected life history characteristics were not assessed. This is because estimates of critical threshold levels of local and absolute abundance and current biomass are not known for many of these stocks. Several best practice gear technology methods to mitigate problematic catch of vulnerable species groups are currently employed: monofilament leaders, whole fish for bait, single-hooking fish bait, no lightsticks, and no fishing at shallow submerged features. Setting terminal tackle below 100 m and carrying and using best practice handling and release equipment were methods identified to reduce fishing mortality and injury of vulnerable species. More information is needed to determine if weaker hooks should be prescribed to mitigate cetacean bycatch. The large benefit to sea turtles of replacing remaining J-shaped hooks with circle hooks might outweigh a possible small increase in elasmobranch catch rates. The consumption of 2024 l of fuel per tonne of landed catch, which is within the range of available estimated rates from similar fisheries, could be reduced, reducing greenhouse gas emissions, through more frequent maintenance and upgrading vessel equipment and materials. Observer data quality may be adequate to support a quantitative Level 3 ERA to determine the significance of the effect of various factors on standardized catch rates and to estimate population-level effects from fishing mortality.     

Public awareness of the economic potential and threats to sharks of a tropical oceanic archipelago in the western South Atlantic

Conservation actions for sharks are hampered partly by the negative beliefs and inaccurate knowledge about them among the general public. This paper investigated the knowledge and attitude of residents and tourists towards shark species of Fernando de Noronha Archipelago, a marine protected area, and one of the major ecotourism destinations in Brazil. Findings showed that residents had a lower knowledge of sharks and less positive attitudes towards sharks than tourists. Even though residents did not see sharks as threats to humans and they were aware of the role of the archipelago as a shark nursery, they did not completely understand the sharks' ecological and economic importance. This distinction between residents' and tourists' perceptions of sharks demands different strategies to assure engagement in management and conservation policies relating to both groups. Management actions focusing on providing enjoyable experiences with sharks to residents and enhancing their participation in tourist activities related to sharks are presented. They would require innovative cooperation between scientific, management and environmental institutions to build initiatives aimed at increasing the knowledge and improving attitudes of residents towards shark conservation and to homogenise conservation values held by the entire public on the archipelago.     

Resolving environmental issues in the southern Brazilian artisanal penaeid-trawl fishery through adaptive co-management

Many conventional management strategies have been demonstrated to be ineffective in achieving sustainable fisheries, and new approaches are required to overcome existing environmental, social and economic problems. Adaptive co-management represents the combination of a learning-by-doing approach (adaptive management) involving all related and legitimate stakeholders in the decision-making process (collaborative management). In this study, the relevant experiences from a fishery in southern Brazil are reported. The first section of the paper summarizes the broad history of national fisheries and their management. Then the southern Brazilian artisanal penaeid-trawl fishery is briefly described and the three main problems associated with the common gears used are discussed, including their (1) poor size and species selectivities, (2) poor efficiencies, and (3) their mechanical impacts on benthic habitats. Finally, a framework is proposed to address the environmental and socio-economic issues in the fishery and its implementation discussed via an adaptive co-management approach.     

Malaysian fisheries policy : Search for new grounds

Past fisheries development policies in Malaysia are assessed and new grounds for managing the Malaysian fisheries are explored. Some incompatibility in the goals for fishery development are discerned, especially those of increasing domestic landings through mechanization and resource conservation. Future management efforts should be based on a fuller understanding of the fishery stock and regional management of fish stocks. Aquaculture is often seen as a plausible alternative in order to augment supplies from the capture fisheries. A comprehensive multidisciplinary approach is needed to transform and commercialize traditional, experience-dependent culture systems into technology-packaged systems based on scientific methods. There is also substantial potential for the development of recreational fisheries.     

Status of Kuwait's fishery resources: Assessment and perspective

For the first time, the production of fisheries in Kuwait was assessed both quantitatively and qualitatively by comparing the production of the late 1980s and the mid-2000s using official data. The results indicate that total fisheries production has declined over time, with local production (artisanal and industrial) having decreased by approximately 25%, while imports increased by 25%, representing 62% of the total fisheries production over time. Current consumer preferences have led to increased demand of fish species formerly having inferior commercial importance. The verified per capita fish consumption in 2010 was 22.32 kg yr⁻¹ suggesting the existence of an unrecorded supplementary supply of fish. Predictions show a dramatic decrease in fishery production by 2025, with a low supply of only 0.5 kg per individual per annum. The results have practical implications for legislators’ management strategies for the sustainability of local fishery stocks.     

The end of shark finning? Impacts of declining catches and fin demand on coastal community livelihoods

For several decades, fishing sharks for their fins has provided important livelihoods for eastern Indonesian coastal communities that fish the Halmahera, Arafura and Timor Seas. Fishery and interview data collected in 2012-13 from three case studies on the islands of Seram, Aru and Rote were used to examine changes in shark fishers’ livelihoods over the preceding 20 years. While recent declines in catches and shark fin prices have had a substantial impact on fishers’ livelihoods, the fishery's low visibility in some areas of its geographic range and its political complexity in general have meant that government and international development agencies have largely been unaware of this impact. Many respondents remembered the Asian Financial Crisis in 1997-98 and the turn of the millennium as a time when sharks were still abundant and shark fin prices high, but were concerned about the on-going fall of shark fin prices since March 2012. High-value species, particularly guitarfish, hammerhead and sandbar sharks were most affected, losing up to 40% of their pre-2012 value. These changes, combined with the loss of fishing grounds, few attractive options for alternative income and restrictive debt relationships with shark fin bosses, have led some fishers to resort to high-risk activities such as blast fishing, illegal transboundary fishing, and people smuggling. This paper examines the multi-layered causes and consequences of fishers’ decision-making in response to adverse changes in their fishery, and explores options and obstacles to pursuing livelihoods that carry lower environmental, financial and personal risks.