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《Marine Policy》2016
Ecosystem-based fisheries management (EBFM) is often discussed by fisheries managers and stakeholders as a potential goal. EBFM is based on a multi-species approach, which varies significantly from the single species fisheries management (SSFM) approach currently practiced under the U.S. Magnuson-Stevens Fishery Conservation and Management Act (MSFCMA). EBFM is “holistic” and considers “all factors,” but it is impossible for management to incorporate all factors into EBFM. This study sought to improve understanding of factors contributing to or preventing progress toward EBFM implementation in the Mid-Atlantic Fishery Management Council (MAFMC) and New England Fishery Management Council (NEFMC), focusing on Council member and stakeholder beliefs, attitudes, and mutual understanding. Objectives included determining mutual understanding between MAFMC and NEFMC members and stakeholders about EBFM and identifying MAFMC and NEFMC member and stakeholder preferences for EBFM definitions, practices, and outcomes, and prioritizing which aspects of EBFM managers and stakeholders find most important. Stakeholders included commercial fishermen, recreational anglers, nongovernmental organization (NGO) leaders, and Scientific and Statistical Committee (SSC) members. Over 1000 survey responses about EBFM from council members and stakeholders in the Mid-Atlantic (MA) and New England (NE) regions were analyzed. The Coorientation Model was used to characterize understanding between the Council and fisheries-related stakeholder groups. For the MA and NE regions, most stakeholders agreed on definitions, practices, and possible outcomes for EBFM. Results suggest that most Council members and stakeholders in the MA and NE regions support a change from SSFM to EBFM at an incremental, intermediate, or complete, gradual (5–10 years) pace. The application of the Coorientation Model to EBFM and the fishery management councils provided insights into how an improved understanding of the attitudes, beliefs, and mutual comprehension of Council members and stakeholder groups could potentially facilitate the implementation of EBFM. Council members and stakeholders responded similarly to, and Council members correctly predicted stakeholder responses about, EBFM definitions, practices, and outcomes. These findings suggest that Council member and stakeholder agreement and understanding are not barriers to MAFMC and NEFMC adoption of EBFM. 相似文献
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Our aim is to analyse the profitability of the Spanish swordfish fleet in the North Atlantic on the basis of the estimate of the gross profit per standard vessel, the average yield and the investment payback period (PP). The swordfish fleet has grown over the last decade to become the main producer in this fishery and one of the most stable fleets of all the Spanish fisheries. The results obtained show increases in profit per vessel, although there was a slight decrease in the final year studied, relatively high rates of return and PP shorter than the average life of one of the fleet's standard vessels. 相似文献
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Subsequent to extension of fishery jurisdiction in 1977 it was Canadian policy to favour the inshore sector in rehabilitation of the Canadian groundfish fishery. Catch allocation, limited entry licensing and vessel replacement policies were implemented, which at first allowed and then increasingly attempted to limit inshore fleet expansion, which was being encouraged through financial assistance programmes. New regulatory authorities wer obtained to deal with the increasingly difficult task of limiting annual harvests to catch quota levels. A 1986 study concluded that the licensed capacity of the Nova Scotia inshore fleet was approximately four times that required to exploit the resource at target levels. As a result of a government task force report released in January 1990, substantial changes were made in the control of fishing by inshore fleets, including establishment of an individual boat catch quota system for some sectors. This article documents the regulatory actions taken to date to control inshore fleet development and annual fishing activities, and the responses of fishermen to these, as a possible guide to the implementation of new approaches. 相似文献
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The northern New England beach wrack community with special reference to the cosmopolitan amphipod crustacean, Orchestia platensis, was examined at estuarine and open coastal habitats. Beach wrack was dominated by the plant genera Ascophyllum, Zostera, Spartina and Chondrus, and was most abundant during spring and late summer. Animal community numbers, biomass and frequency in fresh to moderately decomposed wrack were dominated by O. platensis throughout the year at all habitats; oligochaetes and Collembola were also important. The abundance of O. platensis showed high spatial and temporal variability, with low abundance generally associated with decreased amounts of wrack during colder months. An exception was the winter presence of the species at one estuarine habitat, in patchy aggregations within gravel-cobble refuges. The abundance of O. platensis averaged 1280 (0.04 m2)−1, with a maximum of 7040 (0.04 m2)−1. The life cycle of O. platensis is bivoltine, with summer-hatched young reaching maturity within 1 month. Laboratory studies indicate females with up to 4 broods (30 days)−1, averaging 18 eggs brood−1.Orchestia platensis is omnivorous, eating fresh plant tissue, live oligochaetes, Limulus eggs and diatom ‘fuzz’. The rate of laboratory consumption of algae and Zostera was 0.05 mg plant mg−1 wet body weight day−1. Presumptive predators of O. platensis are juvenile green crab, Carcinus maenus, and the earwig. Anisolabis maritima. The mobility, aggregation and aggressiveness of O. platensis assist the species in establishing and maintaining populations in the rigorous wrack habitat. The general competitive superiority of O. platensis over its congener, O. gammarella, and the co-occurrence of these species on both eastern and western Atlantic shores is discussed. 相似文献
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《Marine Policy》2014
Biodiversity hotspots have been used extensively in setting conservation priorities for marine ecosystems. A recent Nature publication claims to have uncovered new latitudinal gradients in the evenness of reef communities and new reef hotspots based on functional diversity. Simulation models show that the purported evenness gradient is a mathematical inevitability of differences in species richness and detectability between vastly different marine ecosystems, namely ‘reefs’ in tropical, temperate, and polar regions. Constraints on evenness, along with disparity amongst communities in possible functional traits, cast doubt on the utility of global functional diversity comparisons for management of marine systems. 相似文献
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Andalusia is a region of Spain with an area of some 90,000 km2 and almost 900 km length of coastline. It has an important tradition in the fishing industry that makes it one of the areas of the European Union where fisheries policies have a great significance for the population. The present statistical study deals comprehensively with the so-called “artisanal fleet”, especially in respect of data on the typology of vessels (construction particulars) and on the extractive effort made (distances and depths where they fish, duration of fishing voyages, the fishing gear used and target species), with the aim of presenting a new approach in the policies for regulating this important fisheries sector. 相似文献
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Marine fish discarding has become a contentious environmental issue, but little attention has been paid to the moral grievances that sometimes underlie discarding practices. This article explores such a moral grievance through a case study of the under-10 m fishery in Sussex, England, where discarding of cod (Gadus morhua) has become a highly charged issue, skippers blaming it on unjust quota allocations. The moral claim to a greater quota allocation is analysed using two conceptions of distributive justice, entitlement and desert. The conclusion reached is that the under-10 m fleet’s entitlement arguments for a higher quota are weaker than their desert arguments, but that entitlement arguments weigh more heavily than desert arguments with government when it allocates quota. 相似文献
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Groundwater plays an important role in New Zealand water supplies and hence monitoring activities are conducted regularly. Most monitoring programmes aim to evaluate groundwater chemistry and almost completely overlook the microbial component in this ecosystem. In our present study, the bacterial community structure of groundwater in the Wairarapa Valley was examined using the terminal restriction fragment length polymorphism (T-RFLP), and relationships between bacterial community structure and groundwater chemistry, aquifer confinement and groundwater usage were explored. In addition, the results from this study were compared with a previous T-RFLP survey of the same area in an attempt to detect changes in bacterial community structure over time. The data obtained suggested that bacterial community structure was related to groundwater chemistry, especially to redox conditions. Species composition showed minimal variation over time if groundwater chemistry remained unchanged. These findings reflect the potential of using bacterial communities as biological indicators to evaluate the health of groundwater ecosystems. We suggest that it is important to include this type of broad bacterial diversity assessment criteria into regular groundwater monitoring activities. 相似文献
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根据2012年5月(春季)、8月(夏季)、11月(秋季)和2013年2月(冬季)在台山列岛的拖网定点调查数据,对该海域渔业资源种类组成、优势种、物种多样性、资源密度(质量及数量密度)的空间分布及其季节变化等群落结构特征进行分析研究。结果表明,共记录台山列岛渔业生物136种,隶属于18目63科98属,其中鱼类80种,虾类16种,蟹类28种,口足类3种,头足类9种;优势种共有22种,口虾蛄(Oratosquilla oratoria)是唯一四季共同的优势种;Shannon Wiener种类多样性指数(H′)全年平均值为2.88(范围:2.80~2.95),Pielou均匀度指数(J′)全年平均值为0.69(范围:0.65~0.72),Margalef丰富度指数(D)全年平均值为6.99(范围:5.76~7.69),夏季群落多样性较高;从渔业资源质量平均密度看,春、夏季最大值都出现在05站点,分别为640.70 kg/km2和1 039.31 kg/km2,秋季最大值出现在03站点,为1 187.48 kg/km2,冬季最大值出现在04站点,为683.24 kg/km2,从渔业资源数量平均密度看,春、夏季最大值都出现在05站点,分别为170.68×103尾/km2和123.69×103尾/km2,秋季最大值出现在01站点,为119.71×103尾/km2,冬季最大值出现在04站点,为133.27×103尾/km2。总体来说,台山列岛周边海域渔业资源物种较多,种间分布均匀,群落结构稳定。 相似文献
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Spatio‐temporal variations in demersal fish assemblages and diversity in the northern Gulf of St. Lawrence (Canada) 下载免费PDF全文
Species diversity is generally considered one of the key factors of ecosystem resilience in response to anthropogenic pressures, including fishing. In this context, the spatial and temporal changes in demersal fish assemblages and species diversity were investigated in the northern Gulf of St. Lawrence (Canada), over a 20‐year period (1990–2010). Data were obtained from the summer research survey conducted by the Department of Fisheries and Oceans, and include commercial and non‐commercial species. The study covers the period of groundfish fishery collapse, the moratorium period, and the post‐moratorium period, and reflects various modifications in management. Multivariate statistical methods revealed two communities. A coastal community corresponds to strata located above 200 m depth and a deeper community located in the deep channels. Interannual differences in the composition of fish assemblages were observed and are mainly due to the changes in the relative biomass of some dominant species. Three diversity indices (Shannon–Wiener, Simpson's Index of Diversity and Motomura's constant) indicate a slight but significant increase of the diversity over time. This trend is due to the increase of the relative biomass of low‐rank species, which may have been favoured by the prohibition of groundfish trawling after 1997 in that region. The geographical distribution of the Shannon–Wiener index also shows temporal dynamics reflecting the biomass distribution of dominant demersal species. 相似文献
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New Zealand's exclusive economic zone encompasses a significant fishery that is managed by a market-based quota management system. Since the introduction of this regime in 1986 over 3000 fishers have exited the industry. These exiters are predominantly small-scale fishers. This study profiles a sample of the exiters, using information provided on the Ministry of Fisheries database and through a questionnaire sent to the exiters themselves. The profile includes information on the scale of exiters, their typical methods of fishing, the importance of time and exit price to the exit decision, and post-exit employment outcomes. 相似文献
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Harvest cooperatives were implemented in several US fisheries over the last decade during a period when US law prohibited implementation of any new individual fishery quota (IFQ) systems. Harvest cooperatives provided an alternative to individual quotas as a means to end the race for fish and increase fishery profitability. The prohibition on new IFQ systems in the US was lifted, but harvest cooperatives remain a more feasible and perhaps a superior alternative to IFQs for some fisheries. The New England Fishery Management Council is on the verge of implementing a new management system for the groundfish fishery based on harvest cooperatives known as “sectors”. This paper describes the New England sector management system and discusses a number of advantages but also some drawbacks relative to IFQs. It argues that a hybrid of the two approaches could have advantages over either. 相似文献