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131.
In response to recommendations made by a recent performance review, the Indian Ocean Tuna Commission (IOTC) is attempting to develop a quota allocation system (QAS) for management of the tuna and tuna-like species of the Indian Ocean. As “first-movers” in the process, Indonesia, the Seychelles, the European Union, Iran, and the Republic of Korea made contrasting proposals to the IOTC in March 2011 on possible QAS form and structure. Structure (the factors to be taken into account in determining allocation) is critical as it will determine on a long term basis the share accruing to each IOTC member state of the estimated USD 2-3 billion worth of tuna caught in the Indian Ocean each year. This article records and discusses the content of these first steps towards QAS formulation by placing them in the context of rights-based management as applied to the offshore areas falling under tuna RFMO management. The options proposed in March (which the IOTC is still considering) all have a similar architecture but result in sharply divergent allocation outcomes. Despite the sophistication of some of the proposals, the recent IOTC review suggests that the regulatory and management capacity of the IOTC does not match the science and enforcement requirements appropriate to these recent proposals. Perhaps efforts to improve IOTC performance need to be made in parallel with discussions on QAS definition and implementation. To further advance the debate and also concretely demonstrate likely economic outcomes, the article provides indicative monetary valuations of quota allocations proposed. It uses a range of potential historical reference periods (5, 10, 15, and 20 years). 相似文献
132.
Marine populations in Europe are in decline due to the unsuccessful results of the Common Fisheries Policy. By combining data of scientific recommendations from ICES, TACs approved and reported landings with an age-structured model, the objectives of this paper are to investigate the level of compliance of the TAC regulation, and the level of enforcement and its economic impact on fishery resources. The results presented here suggest that while there does not exist a regular pattern between TAC proposal and TAC approved, there is a clear pattern between TAC approved and reported landings. As a consequence, there is a regular lack of enforcement at national fisheries authority level. The paper also presents results of the recovery plans for the Southern hake and the Atlantic cod fisheries as case studies to illustrate the level of enforcement based on collusion between national fisheries advisers and industry. The results from both cases studies analyzed here indicate that drastic solutions could generate positive results for the recovery of the stocks, but perhaps they are not always the best measure in fisheries management due to the high economic losses for fishermen and social effects on coastal communities in the short and medium term. Finally, this work demonstrates that if the recovery plans had been implemented, the net present profits for both fisheries would have increased over time. 相似文献
133.
基于2006~2007年福建沿岸海域4个航次的底拖网调查,分析了福建沿岸海域石首鱼科鱼类的资源现状.结果表明:4个航次共捕获石首鱼类16种,其中春季捕获石首鱼类10种,夏季和冬季均捕获14种,秋季捕获12种.不同航次捕获的石首鱼类占所有鱼类总渔获量的比例为10.43%~23.23%,平均15.71%.平均资源密度和平均个体密度分别为81.49 kg/km2和3 663.06 ind./km2.平均资源密度和平均个体密度均以秋季最高,分别为130.02 kg/km2和5 702.64 ind./km2.闽东沿岸海域、闽江口及其附近海域、闽中沿岸海域和厦门沿岸海域石首鱼类的全年平均资源密度分别为70.75、96.23、22.54和84.57 kg/km2.在各种石首鱼类中,叫姑鱼(Johnius belengerii)的资源密度和个体密度最大,其次是丁氏(Wak tingi).叫姑鱼的相对重要性指数最高,为871.01,仅叫姑鱼为优势种.与近20 a前的调查资料相比较,石首鱼类的渔获量占鱼类总渔获量的比例升高,但资源密度显著下降,必须采取措施,避免开发强度的继续增加,以利于其资源的可持续利用. 相似文献
134.
This article studies the participation of stakeholders in climate change decision-making in Alaska's National Parks. We place stakeholder participation within literatures on environmental and climate change decision-making. We conducted participant observation and interviews in two planning workshops to investigate the decision-making process, and our findings are three-fold. First, the inclusion of diverse stakeholders expanded climate change decision-making beyond National Park Service (NPS) institutional constraints. Second, workshops of the Climate Change Scenario Planning Project (CCSPP) enhanced institutional understandings of participants' attitudes towards climate change and climate change decision-making. Third, the geographical context of climate change influences the decision-making process. As the first regional approach to climate change decision-making within the NPS, the CCSPP serves as a model for future climate change planning in public land agencies. This study shows how the participation of stakeholders can contribute to robust decisions, may move climate change decision-making beyond institutional barriers, and can provide information about attitudes towards climate change decision-making. 相似文献
135.
The emergence of export markets for high-value seafood products tends to produce a predictable pattern of serial depletion of resources and social disruption in coastal communities, a phenomenon described as ‘the tragedy of the commodity’. The sea cucumber trade epitomizes these challenges, with cases of rapid growth followed by fishery collapse documented across the Indo-Pacific and the majority of assessed stocks worldwide overexploited. Is this ‘boom-bust’ sequence inevitable? We examine three cases of resistance to the sea cucumber trade from Palau, Pohnpei, and Yap. Despite the overwhelming short-term financial incentives to export, fishers, youth, elected and traditional leaders, and civil society organizations coordinated to ban the trade at its peak, using public protest, court battles, and customary and statutory law. We show that, like the tragedy of the commons, Indigenous peoples and local communities can organize to resist the tragedy of the commodity. They do so by asserting Indigenous values, rights, and institutions, recommonizing the resource and preventing fisheries collapse. These cases challenge the inevitability of the tragedy of the commodity and the narrative of poor fishers as vulnerable and disempowered. 相似文献
136.
Christophe Béné Louisa Evans David Mills Solomon Ovie Aminu Raji Ahmadu Tafida Amaga Kodio Famory Sinaba Pierre Morand Jacques Lemoalle Neil Andrew 《Global Environmental Change》2011,21(4):1173-1184
Resilience thinking is an important addition to the range of frameworks and approaches that can be used to understand and manage complex social–ecological systems like small-scale fisheries. However, it is yet to lead to better environmental or development outcomes for fisheries stakeholders in terms of food security, improved livelihoods and ecological sustainability. This paper takes an empirical approach by focusing on the fundamentals of resilience thinking to evaluate its usefulness in developing relevant management interventions in small-scale fisheries in the Niger River Basin in West Africa. The paper presents the outputs of a participatory assessment exercise where both fishery communities and local experts were involved at two different scales. The resilience frame used was designed to facilitate the identification of socially defined thresholds that help delineate the desirability of the current system configuration and provides a diagnosis framework that tailors management solutions to problems in local context. The analysis highlights some key contributions from resilience thinking to the challenge of diagnosis in small-scale fisheries management in developing countries, as well as important contributions that emerge from taking a pragmatic and critical approach to its application. 相似文献
137.
Esler D Ballachey BE Trust KA Iverson SA Reed JA Miles AK Henderson JD Woodin BR Stegeman JJ McAdie M Mulcahy DM Wilson BW 《Marine pollution bulletin》2011,62(3):609-614
We examined hepatic EROD activity, as an indicator of CYP1A induction, in Barrow’s goldeneyes captured in areas oiled during the 1989 Exxon Valdez spill and those from nearby unoiled areas. We found that average EROD activity differed between areas during 2005, although the magnitude of the difference was reduced relative to a previous study from 1996/1997, and we found that areas did not differ by 2009. Similarly, we found that the proportion of individuals captured from oiled areas with elevated EROD activity (?2 times unoiled average) declined from 41% in winter 1996/1997 to 10% in 2005 and 15% in 2009. This work adds to a body of literature describing the timelines over which vertebrates were exposed to residual Exxon Valdez oil and indicates that, for Barrow’s goldeneyes in Prince William Sound, exposure persisted for many years with evidence of substantially reduced exposure by 2 decades after the spill. 相似文献
138.
Sedimentological analyses of 289 years (AD 1718-2006) of varved sediment from Shadow Bay, southwest Alaska, were used to investigate hydroclimate variability during and prior to the instrumental period. Varve thicknesses relate most strongly to total annual discharge (r2 = 0.75, n = 43, p < 0.0001). Maximum annual grain size depends most strongly on maximum spring daily discharge (r2 = 0.63, n = 43, p < 0.0001) and maximum annual daily discharge (r2 = 0.61, n = 43, p < 0.0001), while varve thickness is poorly correlated with maximum annual grain size (r2 = 0.004, n = 287, p = 0.33). Relations between varve thickness and annual climate variables (temperature, precipitation, North Pacific (NP) and Pacific Decadal Oscillation (PDO) indices) are insignificant. On multidecadal timescales, however, regime shifts in varve thickness and total annual discharge coincide with shifts in NP and PDO indices. Periods with increased varve thickness and total annual discharge were associated with warm PDO phases and a strengthened Aleutian Low. The varve-inferred record of PDO suggests that any periodicity in the PDO varied over time, and that the early 19th century marked a transition to a more frequent or detectable shifts. 相似文献
139.
国外海洋渔业准入制度的实践分析 总被引:1,自引:0,他引:1
唐建业 《广东海洋大学学报》2011,31(2):1-6
捕捞生产的准入是进行海洋渔业资源有效管理的必要条件。综合相关国家渔业管理发展过程,准入制度可能有三种类型:初步准入制度、投入型准入制度和产出型准入制度。准入的对象涉及渔船、渔获及渔具等。从实践经验看,在渔船数量扩展前,建立有效的准入制度的成功概率相对较大;如果现有的捕捞能力已经远超过渔业资源的承载能力时,投入型准入制度虽然还是十分重要,但在削减捕捞能力方面作用有限;产出型准入制度在一些国家的渔业实践中取得了一定的成功,但存在着诸如总可捕量控制、监测与执法等方面的问题。总体上,捕捞权利与捕捞许可证流转等是实施准入制度过程中应给予关注的两个事项。我国可在现行的捕捞许可证与船网工具指标制度的基础上完善我国投入型准入制度,将渔具纳入管理;在条件成熟的情况下,可适当过渡实施产出型准入制度。 相似文献
140.
The European Common Fisheries Policy (CFP) has failed to deliver on social, economic and ecological goals. This failure is in part the result of a number of social–ecological feedback mechanisms. The policy is currently undergoing reform, with unknown practical outcomes. Here, relatively successful fisheries policies outside the European Union are reviewed. Through interviews and workshops with scientists, managers and other stakeholders, complemented with literature reviews, practices that can create incentives for long-term sustainability are investigated. The focus is on how the provision of clear and trusted scientific evidence can stimulate defensible decisions, in turn creating incentives for compliance, leading to positive social–ecological outcomes. Despite differences between Europe and the investigated case studies, the prospects of an increased regionalization within the European CFP provides the best starting point for implementing best practice identified in this study. 相似文献