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41.
The paper reviews and summarises the literature on regulatory enforcement in fisheries. The focus is on the theoretical literature. First, some of the main contributions from the general economic literature of law enforcement are presented, along with extensions that are considered relevant to the study of fisheries law enforcement. Second, a review of the economic literature of law enforcement applied to the study of fisheries is provided. Finally, the paper presents gaps in the fisheries economics literature on regulatory enforcement and offers some possibilities for future work.  相似文献   
42.
The relationship between stakeholder participation (SP) and the ecosystem-based approach to fisheries management (EBAFM) is often taken for granted, but is actually very complicated. The literature reveals five possible interpretations of this relationship: that they are (1) logically linked; (2) ethically linked; (3) instrumentally linked; (4) complementarily linked and (5) antagonistically linked. We examine these five formulations in the light of recent research on interactions between fisheries and their environment and conclude that the SP/EBAFM relationship manifests itself as predominantly instrumental in character.  相似文献   
43.
Small-scale marine fisheries policy in Vietnam   总被引:1,自引:0,他引:1  
Vietnam's marine fisheries are considered to be small scale and are concentrated in coastal near-shore waters. This has resulted in heavy pressure on near-shore fisheries resources. Near-shore fisheries are considered by fishers and the government to be over-exploited, causing hardship for many coastal communities. This paper reviews and analyzes changes in policy towards small-scale fisheries in Vietnam over the last two decades. The primary issues facing the small-scale fisheries in Vietnam are to restructure the near-shore fisheries and to address over-capacity. Recommended actions include improved fisheries statistics, resources for provincial fisheries staff, and a coordinated and integrated approach involving a mixed strategy of resource management; resource restoration; economic and community development; and new governance arrangements.  相似文献   
44.
This study investigates whether there has been a decline in fish stocks of a coral reef in Thailand, and if so, whether that decline is due to small-scale fishing. The research methods used included fish sampling by UVC, interviews and questionnaires with key informants and artisanal fishers. The results confirmed that there has been a decline in piscivores and carnivores (though not herbivores), and the main perceived threat came not from artisanal but from commercial fishing. Recommendations are to replace the largely unrestricted fishery with a more regulated regime backed by effective enforcement.  相似文献   
45.
Pronounced changes in fauna, extending from the English Channel in the south to the Barents Sea in the north-east and off Greenland in the north-west, have occurred in the late 1920s, the late 1960s and again in the late 1990s. We attribute these events to exchanges of subarctic and subtropical water masses in the north-eastern North Atlantic Ocean, associated with changes in the strength and extent of the subpolar gyre. These exchanges lead to variations in the influence exerted by the subarctic or Lusitanian biomes on the intermediate faunistic zone in the north-eastern Atlantic. This strong and persistent bottom-up bio-physical link is demonstrated using a numerical ocean general circulation model and data on four trophically connected levels in the food chain – phytoplankton, zooplankton, blue whiting, and pilot whales. The plankton data give a unique basin-scale depiction of these changes, and a long pilot whale record from the Faroe Islands offers an exceptional temporal perspective over three centuries. Recent advances in simulating the dynamics of the subpolar gyre suggests a potential for predicting the distribution of the main faunistic zones in the north-eastern Atlantic a few years into the future, which might facilitate a more rational management of the commercially important fisheries in this region.  相似文献   
46.
根据2011年东太平洋赤道附近海域探捕期间采集的1178尾茎柔鱼样本,进行了茎柔鱼的生物学特性研究。结果表明:茎柔鱼胴长范围为201—421mm,平均胴长为290mm,优势胴长为260—320mm;体重范围为200—2650g,平均体重为1000g,优势体重为600—1000g;胴长与体重关系呈幂指数关系;雌、雄性比为2.59:1;性腺成熟度以I、Ⅱ期为主;缠卵腺长和缠卵腺重随着性腺的成熟而逐步增大;雌性初次性成熟胴长为397.2mm;摄食等级以0—1级为主;与其它海域相比,该海域茎柔鱼个体差异明显,主要为小型群体。  相似文献   
47.
Two harbor porpoises in a floating pen were subjected to five pure tone underwater signals of 70 or 120kHz with different signal durations, amplitudes and duty cycles (% of time sound is produced). Some signals were continuous, others were intermittent (duty cycles varied between 8% and 100%). The effect of each signal was judged by comparing the animals' surfacing locations and number of surfacings (i.e. number of respirations) during test periods with those during baseline periods. In all cases, both porpoises moved away from the sound source, but the effect of the signals on respiration rates was negligible. Pulsed 70kHz signals with a source level (SL) of 137dB had a similar effect as a continuous 70kHz signal with an SL of 148dB (re 1muPa, rms). Also, a pulsed 70kHz signal with an SL of 147dB had a much stronger deterring effect than a continuous 70kHz signal with a similar SL. For pulsed 70kHz signals (2s pulse duration, 4s pulse interval, SL 147dB re 1muPa, rms), the avoidance threshold sound pressure level (SPL), in the context of the present study, was estimated to be around 130dB (re 1muPa, rms) for porpoise 064 and around 124dB (re 1muPa, rms) for porpoise 047. This study shows that ultrasonic pingers (70kHz) can deter harbor porpoises. Such ultrasonic pingers have the advantage that they do not have a "dinner bell" effect on pinnipeds, and probably have no, or less, effect on other marine fauna, which are often sensitive to low frequency sounds.  相似文献   
48.
Marine protected areas (MPAs) could be useful as fisheries management tools for the exportation of pelagic eggs, larvae and adult fish. A decreasing gradient of fish biomass across MPAs boundary may indicate export. We determine whether gradients of decreasing biomass of fish assemblage occurred in Tabarca Marine Reserve over two habitats with different continuity across the boundaries, to test if the patchy nature of the marine environment might act as a barrier for the fish export. In general, significant decreasing gradients in total fish biomass and biomass of some species were observed on P. oceanica and rocky substrates, independently of their different continuity through the reserve boundaries. Changes in the multivariate structure of the fish assemblage were correlated with the distance from integral reserve. All of these results support the hypothesis that the exportation of adult fish from Tabarca Marine Reserve occurs, and this process may influence the surrounding fished areas.  相似文献   
49.
This paper details Australian research that developed tools to assist fisheries managers and government agencies in engaging with the social dimension of industry and community welfare in fisheries management. These tools are in the form of objectives and indicators. These highlight the social dimensions and the effects of management plans and policy implementation on fishing industries and associated communities, while also taking into account the primacy of ecological imperatives. The deployment of these objectives and indicators initially provides a benchmark and, over the life of a management plan, can subsequently be used to identify trends in effects on a variety of social and economic elements that may be objectives in the management of a fishery. It is acknowledged that the degree to which factors can be monitored will be dependent upon resources of management agencies, however these frameworks provide a method for effectively monitoring and measuring change in the social dimension of fisheries management.Essentially, the work discussed in this paper provides fisheries management with the means to both track and begin to understand the effects of government policy and management plans on the social dimension of the fishing industry and its associated communities. Such tools allow the consideration of these elements, within an evidence base, into policy arrangements, and consequently provide an invaluable contribution to the ability to address resilience and sustainability of fishing industries and associated communities.  相似文献   
50.
This paper examines the sustainability of United States fisheries managed under the Magnuson-Stevens Fishery Conservation and Management Act, the law that provides the framework for federal fisheries management. Sustainability across a broad suite of criteria, including health of the fished stock, bycatch, and effects on the habitat and ecosystem, was measured against the Monterey Bay Aquarium׳s Seafood Watch criteria for ecological sustainability. Seafood Watch ratings and numerical scores for U.S. federally managed fisheries were analyzed to elucidate strengths and weaknesses among federally-managed fisheries. Of U.S. federally managed fisheries assessed by Seafood Watch, only 2% are rated “Avoid”, and strong ratings for stock health for nearly all fisheries indicate that the Magnuson-Stevens Act is fundamentally succeeding at maintaining or rebuilding the abundance of targeted stocks. The majority (79%) of U.S. fisheries earn the intermediate rating of “Good Alternative”, and 19% earn the top rating of “Best Choice”. Given that U.S. fisheries management is considered among the strongest in the world, this analysis assesses why the majority of U.S. fisheries are not rated “Best Choice”. Fisheries for all variety of species, and using a wide range of fishing methods, can merit “Best Choice” status. However, the majority of U.S. fisheries do not achieve this rating due primarily to bycatch concerns. By improving performance with regard to bycatch, most “Good Alternative” U.S. federal fisheries could reach “Best Choice” status and reap rewards in the marketplace for that recognition. Findings suggest that current science-based management should be maintained in the Magnuson-Stevens Act reauthorization, managers should adopt best practices based on fisheries that are already performing well in the U.S., and more specific federal bycatch mitigation requirements should be implemented.  相似文献   
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