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Diet composition and trophic levels of marine mammals   总被引:16,自引:1,他引:15  
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Fourteen indicators of marine living resource management performance by country, reflecting both their intention to sustainably use the resource within their Exclusive Economic Zones and the effectiveness of their policies, were developed and the performances of 53 maritime countries were assessed. Four rankings of the countries, which jointly account for over 95 percent of the world's marine fisheries landings, are presented here as aggregated scores of the fourteen indicators, using different schemes for weighting the indicators, each reflective of the management preferences identified by the Global Environment Outlook 4 (GEO4) future development scenarios: Market First; Policy First; Security First; and Sustainability First. The resulting rankings differed substantially between the weighting schemes for the top performing countries but less so for the countries performing poorly.  相似文献   
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While the recurrent cost of managing marine protected areas (MPAs) has been documented and estimated, there has been virtually no attempt to quantify the cost of establishing MPAs in the first place. This lack of attention is likely the result of the complexity of the process, involving often uncoordinated efforts of a multitude of governmental and non-governmental entities over a protracted period of time with no clear start and end-point. Using information gathered from a representative subset of MPAs worldwide, this paper presents the first attempt to identify and describe the various components, and explore potential predictors of the total funds spent in the course of establishment. The thirteen MPAs studied vary in size (from <1 to >360,000 km2), location (including near- and offshore in both developed and developing countries), objectives and degree of protection. Variation in MPA start-up costs is shown to be most significantly related to both MPA size and the duration of the establishment phase. Development of a method to estimate the potential cost of establishing proposed MPAs should play a crucial role in the conservation planning process.  相似文献   
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The life spans of demersal species of fishes occurring in deep-waters are much longer and their potential growth rates much lower than those of related shallow water species. As a result, deep-sea demersal fish species are more vulnerable to exploitation. This is because low growth rates relative to the available market discount rate for capital makes it desirable for fishing firms to mine, rather than sustainably exploit, these resources even in the absence of fisheries subsidies. However, it is common knowledge that governments around the world do provide subsidies to their fishing industries. The objective of this contribution is to estimate the global amount of subsidies paid to bottom trawl fleets operating in the high seas, i.e., outside of the Exclusive Economic Zones of maritime countries. Our study suggests that fisheries subsidies to these fleets stand at about US$152 million per year, which constitutes 25% of the total landed value of the fleet. Economic data for bottom trawlers suggest that the profit achieved by this vessel group is normally not more than 10% of landed value. The implication of this finding is that without subsidies, the bulk of the world's bottom trawl fleet operating in the high seas will be operating at a loss, and unable to fish, thereby reducing the current threat to deep-sea and high seas fish stocks.  相似文献   
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As the global trade and market for seafood has grown, so have the twin problems of renaming and mislabeling. Resource scarcity, the potential for greater profits, and weak legislation have all encouraged incorrect labeling, the results of which include consumer losses, the subversion of eco-marketing, further degradation of fisheries resources, and even adverse effects on human health. This paper examines the extent and consequences of renaming and mislabeling seafood, the state of current legislation, and the importance of future policies, with particular attention to the US, where 80% of the seafood is imported and more than one-third of all fish are mislabeled. Policy recommendations include governments’ support for a global mandate to label species, country of origin, and catching or production method on all seafood with high penalties for infractions. Chain of custody standards, such as those recently implemented by the Marine Stewardship Council (MSC), should also be considered for adoption worldwide. To garner support for this legislation, consumers must become better acquainted and concerned with their seafood and its origins.  相似文献   
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