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71.
Japan has a variety of laws to conserve and manage wildlife and biodiversity. This article reviews Japanese laws from conservation of endangered species to the fish and game code, and indicates the issues and challenges they face. It then discusses the issues and challenges for management in the application of the laws.The Japanese statute for conservation of endangered species corresponds to the US Endangered Species Act in appearance, but is much more limited in application and scope. There is no legal channel, such as lawsuits, to assure citizens’ and experts’ input. With respect to general species, management of fish and animals are divided; the fish code’s scope is limited to fishery purposes. Control of wildlife damage is the biggest emphasis in the wildlife code. Reform to bring principles of scientific management into pest control has begun, but conventional culling is still the norm.Japan’ wildlife and fish management is distinctive in relying upon local resource users, instead of on a strong regulatory agency. This is a consequence of traditional communal management, and is apparent in coastal fisheries. The depopulation and exhaustion of rural communities, however, makes it difficult to rely on the community for management. In particular, wildlife management, which relies on aging hunters, is facing a turning point. To address these changes, agencies must be strengthened and lawmakers must enact a mechanism to assure sound science in wildlife policy, while working to revitalize rural communities.  相似文献   
72.
Management strategy evaluation: best practices   总被引:1,自引:0,他引:1       下载免费PDF全文
Management strategy evaluation (MSE) involves using simulation to compare the relative effectiveness for achieving management objectives of different combinations of data collection schemes, methods of analysis and subsequent processes leading to management actions. MSE can be used to identify a ‘best’ management strategy among a set of candidate strategies, or to determine how well an existing strategy performs. The ability of MSE to facilitate fisheries management achieving its aims depends on how well uncertainty is represented, and how effectively the results of simulations are summarized and presented to the decision‐makers. Key challenges for effective use of MSE therefore include characterizing objectives and uncertainty, assigning plausibility ranks to the trials considered, and working with decision‐makers to interpret and implement the results of the MSE. This paper explores how MSEs are conducted and characterizes current ‘best practice’ guidelines, while also indicating whether and how these best practices were applied to two case‐studies: the Bering–Chukchi–Beaufort Seas bowhead whales (Balaena mysticetus; Balaenidae) and the northern subpopulation of Pacific sardine (Sardinops sagax caerulea; Clupeidae).  相似文献   
73.
灯塔市渔业可持续发展评价指标体系的构建及评价   总被引:1,自引:1,他引:0       下载免费PDF全文
为了准确量化和科学评价灯塔市渔业可持续发展能力及影响因素,保证其渔业发展对当代有利、对后代负责。在参照相关研究成果的基础上,结合灯塔市的实际,收集整理了该市渔业2000—2010年共11年的指标数据,构建了包括经济、环境、资源和社会4个子系统、16个指标的可持续发展综合评价指标体系。并以2000年为基准年,计算出了10年各指标相对于基准年的变化率,采用加权综合的计算方法进行综合评价。结果表明:2000—2010年间灯塔市各项渔业指标基本上都处于递增状态,可持续发展能力建设取得了一定的成绩,渔业可持续发展总体上朝着有利于渔业可持续发展的方向变化。研究结果对于全面了解灯塔市渔业发展综合竞争力,促进其渔业全面、协调、可持续发展具有重要意义。  相似文献   
74.
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.  相似文献   
75.
渔业科学知识体系和中国特色的渔业发展之路   总被引:5,自引:1,他引:4       下载免费PDF全文
唐启升 《农学学报》2018,8(1):28-32
渔业应定义为对水生生物资源进行开发利用及其相关经济和科技活动的产业,其渔业科学知识体系的形成始于近代渔业发展阶段。经过100多年的发展,渔业科学知识体系不仅包括渔业生物学、渔业捕捞学、水产养殖学,同时还包括由此带动起来的水产品加工与质量安全、渔业装备与工程、渔业经济与管理等学科。在中国,已从基础研究、水产教育和人才培养、推进产业科技进步等方面形成若干支撑渔业发展的重点学科领域。经过60多年的探索、徘徊、调整和创新,中国渔业走出了一条具有显著中国特色、以养殖为主的发展之路。展望未来,中国渔业必须遵循绿色发展理念,坚持渔业发展与生态环境保护协同共进,大力促进渔业生态文明建设,建设环境友好型水产养殖业和资源养护型捕捞业,促进增殖渔业和休闲渔业新业态的发展,以保证中国特色的渔业持续健康发展,为中国和世界做出新贡献。  相似文献   
76.
刘红卫  贺世杰  王传远 《安徽农业科学》2010,38(26):14579-14581,14584
渤海海洋渔业资源的过度开发与利用,使渤海海洋生物资源严重衰退。分析了渤海渔业资源的内部矛盾及其主要因素,结果表明,由于人类对海洋环境的破坏和不合理利用,造成渤海渔业资源严重衰退。针对目前渤海海洋渔业资源开发现状及其由于过度捕捞造成的海洋环境问题,提出了未来渤海渔业资源的可持续发展的对策。  相似文献   
77.
The status of federally managed fisheries in the United States is well monitored, but the condition of other marine fisheries, whether state-managed, territory-managed or unmanaged, is less understood and often unknown. We used expert surveys to characterize the management systems of non-federally managed fisheries in US coastal marine states and overseas territories. For 311 fisheries, we estimated an overall Fisheries Management Index (FMI) and a qualitative stock status score. These measures were positively correlated, and while a wide range of research, management, enforcement and socioeconomic criteria were partially met (FMI ≥ 0.5) for 66% of fisheries, stock status was considered as partially acceptable (score ≥ 0.5) for only 45% of fisheries and acceptable (score = 1) for only 16% of fisheries. Higher FMI was typically observed in fisheries with greater commercial landed weight, value, or greater recreational catches. Fisheries from continental states had higher FMI than those from overseas territories. Invertebrates and diadromous fish species had higher FMI on average compared to those of marine fishes. Extrapolating results for surveyed fisheries to nearly 2000 non-federally managed US fisheries while stratifying by state and importance designation (based on commercial, recreational, cultural or ecological importance), we estimate a mean overall FMI of 0.48, and estimate that only 19% of fisheries have a reliable estimate of stock status available; both measures are lower than similar estimates for federally managed fisheries. Funding or capacity constraints and information or data limitations were identified as common challenges faced by state agencies in managing fisheries under their jurisdiction.  相似文献   
78.
A statement of the principles and policies of fisheries administration and management is presented as a basis for a plea for linguistic precision and avoidance of ambiguity in the various usages of fisheries science.  相似文献   
79.
In the middle of the 1990s, Pacific saury fishery vessels began to install “size separators” to selectively land large-size class fish with a higher price. Contrary to expectations, this resulted in removal of the separators in 2006 because fishers believed the separators had contributed to price collapses in the 2000s. The intent of this paper is to investigate the effects of separators on both the fishery economy and stock of Pacific saury by simulating population and economic models under a single framework. For this purpose, we developed (1) an age-structured population dynamics model with stochasticity, and (2) an economic model spanning both price and inventory dynamics with stochasticity, in which each set of model parameters were estimated on the basis of time series data. In a 10-year simulation, the harvest quota was set constant from 20,000 to 400,000 t at intervals of 20,000 t, and the effects of separators were incorporated by controlling the catchability of 0-year-old fish. We found that separators increase the expected yield and reduce the deficit risk for harvests of 140,000 t and smaller. However, separators have the opposite effects for harvests of 160,000 t and larger.  相似文献   
80.
This paper combines official data from 1990–2007 for (i) the Total Allowable Catchs (TACs) recommended by International Council for the Exploration for the Sea (ICES) scientists and the proposed and approved TACs and (ii) biomass, recruitment, catches, fishing effort, and current exploitation rates for all marine populations subjected to TAC regulation. The differences between the fishing quotas and the scientific recommendations provided by the ICES were calculated to be 19% after the first CFP reform (1992–2001) and 21% after the second one (2002–2008). In some species, these differences showed a three‐fold increase, in particular those currently considered to be beyond the biological safety limits. Regarding the most important index of abundance, the results also indicate a biomass and recruitment reduction of ~75–85% of the stocks and 90% of catches, whereas the fishing mortality increased in 35% of stocks. In addition, of all populations analysed under TAC regulation, 20% presents an increase in the current exploitation rate, 17% did not show significant changes, and the remaining 63% presented a reduction between 1990 and 2007. These results could contribute to the recovery of stocks. However, following the methodology used by Worm et al. who reported that 6 out of the 10 (60%) marine ecosystems examined showed current exploitation rate values that were significantly higher than those that provide the maximum sustainable yield, this study demonstrates that 86% of the populations regulated by TACs present values higher than exploitation rates that give maximum sustainable yield, following an alarming pattern of exploitation.  相似文献   
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