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1.
Four major phases in the exploitation of Antarctic marine living resources are identified and briefly described, viz. exploitation of seals, whales, finfish and krill Euphausia superba Dana. The pattern of exploitation has shifted from one group of resources to another. The recent efforts of the Commission for the Conservation of Antarctic Marine Living Resources are considered in relation to management of finfish exploitation and to the development of a scientifically based management plan for krill. Special emphasis is given to the data required for the effective management of the krill fishery, per se, given the current limited knowledge of the potential yield of the resource and in the face of uncertainty concerning key aspects of the species' biology/ecology. A recent South African initiative aimed at developing a practical management strategy for the Antarctic krill resource is described.  相似文献   

2.
利用1997-2008年南极磷虾产量及各月南极海冰面积数据,分析南极磷虾产量的时空分布,以及海冰对南极磷虾资源丰度的影响。结果表明,近年来南极磷虾年平均产量在11万t左右,主要来自48渔区,渔汛期为3—7月。但不同渔区(48.1区、48.2区和48.3区)在不同年份和季节,其产量和CPUE均有明显差异。分析认为,48区...  相似文献   

3.
21世纪以来底拖网渔业的快速发展给脆弱海洋生态系统(VME)带来极大威胁,导致公海深海渔业发展不可持续以及海洋生物多样性降低。为更好地实现养护海洋渔业资源和保护海洋生物多样性的目标,同时为我国在保护VME以及管理公海深海渔业方面提供参考,文章分析八大区域渔业管理组织(RFMO)针对VME保护采取的系列措施及其保护VME的可行性,针对存在的问题提出对策建议,并对我国在RFMO中保护VME进行展望。研究结果表明:《公海深海渔业管理国际准则》在RFMO保护VME的实践中发挥重要的指导作用;RFMO采取的措施限制深海渔业活动,但为保护VME和养护海洋渔业资源提供重要基础和保障;未来RFMO应加强信息共享和技术合作,发展VME分布预测技术,同时在保护海洋生物多样性方面积极开展双边和多边合作;我国应进一步研究和实践基于生态系统的渔业管理方法,平衡保护与开发利用的关系,积极参与国际渔业管理和VME保护并促进合作,加强南极海域海洋保护区综合治理。  相似文献   

4.
Ecosystem Based Fisheries Management (EBFM) requires the consideration of potential impacts of a commercial fishery on all components of the ecosystem. Assessment of the impact of commercial fishing on marine mammals generally focuses on species at known risk from bycatch. For cetaceans in particular, inclusion under the Threatened, Endangered and Protected (TEP) species component of Ecological Risk Assessment for the Effects of Fishing (ERAEF) can seem redundant if a species is already known to be at risk or is not thought to interact with the fishery with consequences for its conservation. A spatially and temporally explicit Productivity Susceptibility Analysis (PSA) procedure was developed for inclusion under ERAEF to allow cetacean species to be screened for risk. The technique is demonstrated by assessing the potential risk to harbour porpoise and minke whales from a number of static gear fisheries. The results demonstrate that although a fishery might pose high risk to a species, low or moderate risk areas can exist within the range of the fishery, enabling management measures to focus on areas of greatest risk. Designed to complement and support existing methods of bycatch assessment, this approach is a repeatable and standardised assessment, the outputs of which can be used to systematically document the level of risk posed to different species in a transparent way to aid the inclusion of cetaceans in ERAEF and EBFM both now and in the future.  相似文献   

5.
Emerging fisheries and changes in fishery practices are not always readily apparent, nor are their impacts on non-target species such as seabirds, sea turtles, and marine mammals. Data from several different sources led managers to discover high rates of sea turtle bycatch in an inshore large-mesh gillnet fishery in North Carolina, USA, particularly the emerging deep-water gillnet fishery. This paper reviews the history of how increased numbers of observed stranded sea turtles in 1999 led to the discovery that turtles were becoming entangled in the large-mesh gillnet fishery in Pamlico Sound, North Carolina. It also demonstrates how a variety of data sets from fisheries observers, aerial surveys, and fisheries statistics programs contributed to shaping management of the large-mesh gillnet fishery in Pamlico Sound to decrease turtle bycatch and now point towards the need of additional assessment of gillnet bycatch in other parts of North Carolina. Finally, potential approaches are discussed for a more timely detection of future fishery conflicts and development of a plan to reduce otherwise inevitable bycatch and disruptions to fishing effort.  相似文献   

6.
During the 1970s, several factors conspired together to turn the attention of many of the world's major fishing nations towards some of the untapped resources of the oceans. Since that time, the Antarctic krill fishery has been developing quickly — but hardly dramatically. Nonetheless, it has been in an exponential growth phase which, if maintained, would push krill to the top of the species table in the next few years.  相似文献   

7.
为促进辽宁省渔业尤其是海洋渔业的可持续发展,文章综合相关统计数据,运用产业结构三轴图和灰色关联度分析方法,系统分析辽宁省渔业产业结构及其主要产业的发展情况以及6个主要产业对海洋渔业的影响程度,并提出发展建议。研究结果表明:辽宁省渔业第一产业仍占主体地位,但第二和第三产业占比逐渐提高,产业结构三角形的重心呈左旋趋势;渔业第一产业有所优化,第二产业对渔业经济发展起到支柱作用,第三产业以水产品运输业为主;海水产品加工业和运输业对海洋渔业的影响程度最高;未来辽宁省应继续科学发展海水养殖业、远洋渔业、水产品加工业、水产品运输业、休闲渔业和“互联网+渔业”,不断优化渔业产业结构。  相似文献   

8.
为测度当前我国休闲渔业的发展规模,选取2013—2018年的休闲渔业产值和渔业经济产值为变量,构建了直接贡献率、间接贡献率和回归分析法建立的边际贡献率模型,测算了休闲渔业对渔业总产值的贡献度。结果表明,2014—2018年的直接贡献率分别为4.38%、4.95%、14.3%、6.58%和12.5%,2014—2018年的间接贡献率分别为0.317%、0.261%、0.752%、0.403%和0.533%,2013—2018年,休闲渔业对于渔业经济总值的边际贡献率为9.9%,由数据得出,当前我国休闲渔业规模还很小,发展水平也很低,整体实力也很薄弱。为此提出:加大休闲渔业的政策扶持力度;设计最为合理的休闲渔业项目;加大休闲渔业的宣传;加强休闲渔业与高校的合作,培养更多的休闲渔业方向的高精尖人才;推动休闲渔业从业者专业素养整体水平的提高;鼓励休闲渔业从业者之间的帮助;健全完善休闲渔业的监督管理体制;加强组织领导,促进休闲渔业发展。  相似文献   

9.
Whale depredation occurs when whales steal fish, damage fish or damage fishing gear. In Alaska, killer whales (Orcinus orca) and sperm whales (Physeter macrocephalus) primarily depredate on demersal sablefish (Anoplopoma fimbria) and Pacific halibut (Hippoglossus stenolepis) longline fisheries. Quantitative data on whale depredation in Alaska is limited due to low fishery observer coverage and minimal depredation evidence left on longline fishing gear. This study utilized semidirected interviews (n=70) and written questionnaires (n=95) with longline fishermen to examine: (1) perceptions and experiences of whale–fishery interactions in Alaska, (2) effects of depredation on fishing practices, and (3) potential depredation mitigation measures. Eighty-seven percent of fishermen surveyed agreed that whale depredation became worse between 1990 and 2010. Respondents reported changing their fishing practices in response to depredating whales in several ways, including: traveling up to 50 nautical miles and ceasing hauling operations up to 24 h until the whales left the fishing grounds. Respondents fishing in western Alaska, primarily encountering killer whales, were forced to wait longer and travel greater distances than fishermen operating in central and southeast Alaska, regions more affected by sperm whales. Deterrent research, gear modifications and real-time tracking of depredating whales were solutions favored by study participants. Survey respondent answers varied based on areas fished, quota owned, years involved in the fishery and vessel size. This study presents the first statewide evaluation of fishermen's perception and knowledge of whale interactions with the Alaskan longline fleet and is a critical step toward developing baseline data and feasible depredation mitigation strategies.  相似文献   

10.
Individuals with high discount rates are likely not partial to conservation because they are unwilling to sacrifice short term benefits for potentially higher gains in the future. Many reef fisheries worldwide are open access, and fishers under open access systems are theorized to discount the future at an infinite rate. In contrast, fishers in a customary managed fishery can be expected to be more long term oriented, and thus possibly have lower discount rates. The present study tests this hypothesis by eliciting the discount rates of fishers in an open access small-scale reef fishery, and compares these rates to those of fishers in a customary managed reef fishery. Results indicate that fishers in both open access and traditionally managed reef fisheries have high annual discount rates that are on average over 200%. Contrary to expectations, fishers under an open access system are not associated with higher discount rates compared to customary management. It also appears that a larger proportion of open access fishers are more long-term oriented than those in the customary managed fishery, which is encouraging for the future conservation and sustainability of open access fisheries resources.  相似文献   

11.
Antarctic krill, Euphausia superba Dana, has a heterogeneous circumpolar distribution in the Southern Ocean. Krill have a close association with sea ice which provides access to a critical food source and shelter, particularly in the early life stages. Advective modelling of transport pathways of krill have until now been on regional scales and have not taken explicit account of sea ice. Here we present Lagrangian modelling studies at the circumpolar scale that include interaction with sea ice. The advection scheme uses ocean velocity output from the Ocean Circulation and Climate Advanced Modelling (OCCAM) project model together with satellite-derived sea ice motion vectors to examine the potential roles of the ocean and sea ice in maintaining the observed circumpolar krill distribution. We show that the Antarctic Coastal Current is likely to be important in generating the large-scale distribution and that sea ice motion can substantially modify the ocean transport pathways, enhancing retention or dispersal depending upon location. Within the major krill region of the Scotia Sea, the effect of temporal variability in both the ocean and sea ice velocity fields is examined. Variability in sea ice motion increases variability of influx to South Georgia, at times concentrating the influx into pulses of arrival. This variability has implications for the ecosystem around the island. The inclusion of sea ice motion leads to the identification of source regions for the South Georgia krill populations additional to those identified when only ocean motion is considered. This study indicates that the circumpolar oceanic circulation and interaction with sea ice is important in determining the large-scale distribution of krill and its associated variability.  相似文献   

12.
A one-dimensional, temperature-dependent model is implemented to simulate the descent–ascent cycle of Antarctic krill (Euphausia superba) embryos and larvae. Inputs to the model are monthly mean climatologies of ambient temperature and density fields obtained from the World Ocean Atlas Database for Southern Ocean waters. Simulations are done with a 1° resolution at a circumpolar scale, south of 60°S, and the results are interpolated to a 5′ grid to match the resolution of the bottom bathymetry data. Simulations of the descent–ascent cycle using environmental conditions corresponding to the Antarctic krill spawning season (December–March) resulted in unconstrained success in completion of the cycle in water deeper than 1000 m. Continental shelf regions favorable to successful hatching of Antarctic krill embryos are limited to areas along the west Antarctic Peninsula, large areas in the Bellingshausen and Amundsen Seas, offshore of Wilkes Land, and to the east and west of Prydz Bay. These are regions where the Southern Antarctic Circumpolar Current Front is along the shelf slope, the Antarctic Slope Front is absent, and Circumpolar Deep Water is present. The effect of seasonal variability in temperature on the descent–ascent cycle tends to enhance the probability of success in regions offshore of Wilkes Land, Queen Maud Land, and the eastern shelf of the Antarctic Peninsula later in the spawning season. The simulations show that success of the descent–ascent cycle is sensitive to initial embryo diameter and larval ascent rate. Initial embryo diameter may provide an additional constraint on success of the descent–ascent cycle, especially in continental shelf waters, where small embryos tend to encounter the bottom before hatching. The circumpolar distributions of simulated embryo hatching depth and larval success show that all regions of the Antarctic are not equal in the ability to support successful completion of the Antarctic krill descent–ascent cycle, which has implications for the overall circum-Antarctic krill distribution and for the development of nutrient and material budgets, especially for Antarctic continental shelf areas.  相似文献   

13.
《Marine Policy》2002,26(5):345-357
The North Atlantic Ocean has numerous global, regional, and sub-regional instruments for fisheries management. Research for this paper has examined North Atlantic State levels of compliance with these instruments. The study reveals there to be moderate levels of overall compliance, and a latitudinal gradient of compliance with Northern States scoring higher than those in the south. Of particular significance for other global regions, and the future development of international fisheries law, are the findings that: few regional fishery bodies have a systematic program in place to monitor and assess compliance; and despite overall moderate levels of compliance with the conservation and management regimes, most fishery stocks are either overexploited or at risk or collapse.  相似文献   

14.
《Marine Policy》1999,23(1):1-10
Game theory is a formal tool for analysing strategic interaction between a finite number of agents. The fact that usually more than one entity or agent has property rights to fishery resources, has led to an explosion in the use of game theory and applications thereof to analyse fishery management problems. This review shows that game-theoretic modelling has made significant contributions to our understanding of the problems of fishery resource management. However, many challenges still remain. For instance, models of straddling stocks are yet to be fully developed. In addition, fisheries economists have not yet fully exploited the opportunity provided by computational methods now available, and the ever increasing power of computers, to develop more empirical game-theoretic models for practical fisheries management.  相似文献   

15.
北冰洋公海尚处于冰封状态,但气候变暖、海冰加速融化使未来公海出现新渔场成为可能,其战略价值因而得到国际关注。当前,环北极国家已率先展开渔业权益争夺。为分析北冰洋公海渔业事务的国际走势,文章基于博弈论思想,构建非对称懦夫博弈模型及古诺模型来模拟和探究环北极国家在渔业利益争夺中的合作或冲突行为,研究得出:现阶段北冰洋公海渔业权益争端主要表现为渔业管理权的争夺,在该博弈中,非北冰洋沿岸国采取退让策略,沿岸国采取进攻策略,可以达到进化稳定均衡;一旦公海具备捕鱼条件,争端将演化为开发模式选择的博弈,此时,北冰洋沿岸国采取合作开发策略可以有效保护公海渔业资源,并实现国家的长期利益。  相似文献   

16.
Virginia supported the most productive bay scallop (Argopecten irradians) fishery in the United States in 1930, but the fishery disappeared three years later and never recovered. This collapse highlights a tipping point, but managers of extant bay scallop fisheries have not looked to this case for guidance, because the collapse has long been attributed to an exogenous eelgrass (Zostera marina) ‘wasting disease’ pandemic. Consequently, it remains little understood. However, efforts to restore the fishery, following successful eelgrass restoration, now warrant a thorough examination of its economic significance and disappearance. This study comprehensively surveyed information on the original fishery and reconstructed the pre-collapse population to evaluate restoration prospects and management strategies that reduce the risk of future scallop-seagrass system collapses. Harvest records suggest that overharvesting possibly contributed to the Virginia fishery disappearance—a factor that influenced other bay scallop fisheries but did not alarm contemporary managers in Virginia. The harvest peaked before managers observed eelgrass disappearing and exceeded most pre-collapse population estimates. Intensive dredging possibly precipitated a feedback that reduced scallop recruitment by lowering seagrass shoot densities. Managers should, therefore, consider a potential tradeoff between future scallop harvest and eelgrass restoration goals. The restored wild scallop population in Virginia cannot yet support a commercial fishery at historic levels, which removed between 270 and 380x as many individuals. However, the economic risks associated with reestablishing this fishery are low. The collapse did not cause a significant loss in total economic value, because harvesters rapidly shifted focus to clams, supplanting lost scallop revenue.  相似文献   

17.
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.  相似文献   

18.
Study on chemical forms of fluorine enrichment of Antarctic krill   总被引:1,自引:0,他引:1  
I~IOWFluorine is one of fewer biogenic ndcroelernent, which has two thresholds. In certain extentcontent, fluorine plays an ~ant ace in constructing and growing normally for organisms. Incontrast, too high or too low content is not gabs for living being growing (Chen and Yu, 1988).In general, nuorine in seawater is known as one of conversation elements, and the average contentof nuorine of all world ocean seawater is 1. 3o rug/dln3(Chen et al., 1987).Under high fluorine seawat(lr environmen…  相似文献   

19.
The Harvard Ocean Prediction System (HOPS) is configured to simulate the circulation of the Scotia Sea and environs. This is part of a study designed to test the hypothesis that Antarctic krill (Euphausia superba) populations at South Georgia in the eastern Scotia Sea are sustained by import of individuals from upstream regions, such as the western Antarctic Peninsula. Comparison of the simulated circulation fields obtained from HOPS with observations showed good agreement. The surface circulation, particularly through the Drake Passage and across the Scotia Sea, matches observations, with its northeastward flow characterized by three high-speed fronts. Also, the Weddell Sea and the Brazil Current, and their associated transports match observations. In addition, mesoscale variability, an important component of the flow in this region, is found in the simulated circulation and the model is overall well suited to model krill transport. Drifter simulations conducted with HOPS showed that krill spawned in areas coinciding with known krill spawning sites along the west Antarctic Peninsula continental shelf can be entrained into the Southern Antarctic Circumpolar Current Front (SACCF). They are transported across the Scotia Sea to South Georgia in 10 months or less. Drifters originating on the continental shelf of the Weddell Sea can reach South Georgia as well; however, transport from this region averages about 20 months. Additional simulations show that such transport is sensitive to changes in wind stress and the location of the SACCF. The results of this study show that krill populations along the Antarctic Peninsula and the Weddell Sea are possible source populations that can provide krill to the South Georgia population. However, successful transport of krill to South Georgia is shown to depend on a multitude of factors, such as the location of the spawning area and timing of spawning, and variations in the location of the SACCF. Therefore, this study provides insight into which environmental factors control the successful transport of krill across the Scotia Sea and with it a better understanding of krill distribution in the region.  相似文献   

20.
近海渔业的可持续发展对我国渔业经济增长十分重要。文章在对2000—2019年近海渔业资源和水域环境现状分析的基础上,剖析近海渔业存在的问题,如海水养殖资源浪费严重、海洋捕捞过度、渔业专业人才流失和水域环境污染严重等问题。提出基于绿色发展理念的近海渔业从传统产业型向业态创新型转变、资源掠夺型向资源养护型转变和单一生产型向产业链型转变的建议,以期为我国近海渔业的可持续发展提供参考。  相似文献   

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