首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Conflict surrounding commercial fisheries is a common phenomenon when diverse stakeholders are involved. Harvesting reef fish for the global ornamental fish trade has provoked conflict since the late 1970s in the State of Hawaii. Two decades later the state of Hawaii established a network of marine protected areas (MPAs) on the west coast of the island of Hawaii (“West Hawaii”) to protect and enhance the fish resources and alleviate conflict between stakeholders, principally between commercial dive tour operators and aquarium fishers. The perceptions held by these stakeholders on West Hawaii and Maui were evaluated to understand how MPAs influenced conflict dimensions, as the former location had a well-established MPA network designed to alleviate conflict, while the latter did not. This was accomplished by analyzing the following questions: (1) perceptions about the effectiveness of MPAs to alleviate conflict and enhance reef fish; (2) perceived group encounters and threats to coral reefs; (3) willingness to encourage fishing; and (4) value orientations toward the aquarium fish trade. The results indicate the MPAs in West Hawaii were moderately effective for alleviating conflict, encounters between stakeholders occurred on both islands, dive operators strongly opposed commercial fishing and perceived aquarium fishing as a serious threat to the coral reef ecosystem, and polarized value orientations toward the aquarium fish trade confirms pervasive social values conflict. The conflict between these groups was also asymmetrical. MPAs are inadequate for resolving long term conflict between groups who hold highly dissimilar value orientations toward the use of marine resources. Future marine spatial planning and MPA setting processes should include stakeholder value and conflict assessments to avoid and manage tensions between competing user groups.  相似文献   

2.
The global trade in aquatic wildlife destined for home aquaria not only has the potential to be a positive force for conservation, but also has a number of potential risks. The greatest and most documented risk is the potential to translocate species that will become invasive in a new habitat. Although propagule pressure can influence species invasiveness, a high percentage of documented marine aquarium fish that are invasive in the US are uncommon in the trade. Here, the covariation of size with species invasiveness was assessed using a web scraper to collect size, price, life history characteristics, and behavior data from five internet retail stores for 775 species of fish. Fish that routinely exceed 100 cm in total length are traded, nevertheless are typically sold at sizes much smaller than their theoretical maximum. No economic benefit from the sale of species that will outgrow tanks and have a high risk of being released was found. Large fish, including groupers that can achieve weights of 800 pounds, will continue to enter the trade because the growth of aquaculture for commercial food markets is making it easier to acquire these species that also have appealing small life stages, making it easier and less expensive to bring these species into the aquarium trade. The entire trade should consider taking concerted action to limit the trade in fish that are likely to become invasive.  相似文献   

3.
Identifying socio-economic drivers of small-scale fisheries is a fundamental step to understand impacts and pressures on fishery resources, and the behaviour of seafood trade actors. It is especially relevant for developing countries where such information is usually lacking and fisheries management is greatly needed. To address this gap, this study maps the structure of value chains of fish and marine invertebrates caught by small-scale fisheries from São Vicente, Cape Verde (West Africa), and examines the main socio-economic drivers behind the seafood trade on the island. Specifically, it shows how drivers, such as tourism and the local market, shape the preferences for certain species and how they affect the distribution of income among actors involved in the seafood trade. To collect this information, interviews were done with fishers, small-scale traders, market vendors, and restaurant owners, in all fishing communities of the island of São Vicente, in 2015. Tourism and the local market drive the exploitation of a wide variety of marine species, from small demersal low trophic level fish and marine invertebrates, to large pelagic high trophic level fish species. Moreover, the local seafood market, and especially tourism dynamics, contribute to the unequal distribution of income among actor groups, benefiting mostly restaurant owners due to their direct access to tourist consumers. Such findings have implications for local fishery resources management, food security, and fishing communities’ livelihoods.  相似文献   

4.
Papua New Guinea has sometimes been called the world's last frontier for relatively undamaged coral reefs and their resources. In 2007, the country joined its neighbours in the marine aquarium trade. By licensing a private company, Papua New Guinea tried an alternative approach to the introduction of this activity. Under the so-called SeaSmart Programme, over 100 fishers were trained in sustainable collection techniques and handling of organisms, until the programme was shut down in 2010, and replaced by its successor, EcoAquariums PNG. This article contains the first study on the introduction of the marine aquarium trade into Papua New Guinea. It evaluates the overall outcomes of the SeaSmart Programme, lists targeted species, and their prices. The main focus is on the local collectors, and on the impacts of this new activity on them and their communities. Benefits from collecting marine ornamentals are assessed and their contribution to household income is quantified. Perceptions on non-financial benefits of the SeaSmart Programme are also gathered. The empirical work was carried out between September 2010 and February 2011 in the Central Province of Papua New Guinea. A total of 199 fishers including 44 aquarium fishers were interviewed in eight different communities in the Central Province of Papua New Guinea. The results show that marine aquarium fishing does provide benefits to local resource collectors, but also that this “sustainable” way of collecting of marine ornamentals might lead to some depletion.  相似文献   

5.
Spatial marine closures are widely employed and advocated for marine resource management and conservation. Temporal, non-permanent, rotational or periodically harvested area closures have been employed across the Indo-Pacific for centuries and are a common measure within contemporary community-based and co-management frameworks. Although prior evidence suggests that periodic closures may confer fisheries benefits for some taxa or in certain conditions, there is little evidence that they are equally effective for the sustainable management of the many types of small-scale fisheries important in the Indo-Pacific. Case studies of periodic closures are reviewed to highlight the variations in target species, harvesting periodicity and fishing pressure that will influence the fisheries management effectiveness of this tool. Fisheries management benefits are observed for short-lived, fast-growing taxa or for a range of taxa in low fishing pressure situations. Stocks declines are observed for long-lived taxa or for a range of taxa if harvesting is intense. It is argued that community-based and co-management policy and action must better account for these factors when promoting and implementing periodic closures for medium- to long-term fisheries management or conservation goals.  相似文献   

6.
As the world’s largest importer of marine ornamental species for the aquaria, curio, home décor, and jewelry industries, the United States has an opportunity to leverage its considerable market power to promote more sustainable trade and reduce the effects of ornamental trade stress on coral reefs worldwide. Evidence indicates that collection of some coral reef animals for these trades has caused virtual elimination of local populations, major changes in age structure, and promotion of collection practices that destroy reef habitats. Management and enforcement of collection activities in major source countries such as Indonesia and the Philippines remain weak. Strengthening US trade laws and enforcement capabilities combined with increasing consumer and industry demand for responsible conservation can create strong incentives for improving management in source countries. This is particularly important in light of the March 2010 failure of the parties to the Convention on International Trade in Endangered Species (CITES) to take action on key groups of corals.  相似文献   

7.
A re-evaluation of the threat status of New Zealand's marine invertebrates was undertaken in 2009, following earlier review of New Zealand's Threat Classification System and subsequent refinement of the national criteria for classifying threat of extinction to New Zealand's flora and fauna. Sufficient information was available to enable 295 marine invertebrate taxa to be fully evaluated and assigned to a national threat category. The 10 taxa at most risk of extinction (‘nationally critical’) were the giant seep clam Calyptogena sp., the primitive acorn barnacle Chionelasmus crosnieri, O'Shea's vent barnacle Volcanolepas osheai, the stalked barnacle Ibla idiotica, the four-blotched umbrella octopus Cirroctopus hochbergi, the roughy umbrella octopus Opisthoteuthis chathamensis, the giant squid Idioteuthis cordiformis, the large-egged polychaete Boccardiella magniovata and two gravel maggots, Smeagol climoi and Smeagol manneringi. The key threatening processes identified for marine invertebrates were fishing and land-use associated impacts such as sedimentation. We identified no taxa that had improved in threat status as a result of past or ongoing conservation management action, nor any taxa that had worsened in threat status because of known changes in their distribution, abundance or rate of population decline. We evaluated a small fraction of New Zealand's marine invertebrate fauna for their threat status. Many taxa remain ‘data deficient’ or unlisted. In addition to the most threatened taxa, we recommend these taxa and their habitats as priorities for further survey and monitoring.  相似文献   

8.
The protection of imperilled fish species is increasingly urgent given ongoing fisheries declines and the degradation of aquatic habitats. In Canada, threatened aquatic species were less likely than terrestrial species to be listed under the Species at Risk Act (SARA), the main legal instrument for bestowing protection, in the early years of the Act's implementation. In this paper, the existence of economic thresholds that might have hampered the protection of Canadian marine and freshwater fishes is examined. The analysis of the socio-economic data used to inform listing decisions about threatened fish taxa over the past decade reveals that the likelihood of being listed declines non-linearly with increasing estimated costs of protection but does not vary with proposed threat status. The estimated threshold cost (i.e., the point at which the likelihood of not being listed=0.5) was ∼$5,000,000 (∼$1,400,000 to ∼$31,400,000, 95% CI) per decade for freshwater species but only ∼$90,000 ($∼50,000 to ∼$140,000, 95% CI) per decade for marine fish taxa. In fact, no marine fish species with an anticipated cost of listing greater than zero was listed for protection. The presence of existing management legislation and qualitative statements about negative impacts of listing on exploitation generally led to denying protection to marine but not to freshwater species. These findings highlight both a large and inconsistent emphasis on costs of protection in SARA listing decisions, to the detriment of marine fish species.  相似文献   

9.
Current knowledge of the biodiversity of the symbiotic marine siphonostomatoids from South African waters (136 species) is sparse compared to that globally (1 388 species). The difference is especially apparent when taking into account the diversity of fish (more than 2 000 species) and invertebrates (approximately 12 914 species) found in South African waters, all of which are all potential hosts of symbiotic siphonostomatoids. Most reports of symbiotic siphonostomatoids from South African waters are from Chondrichthyes and represent 80% of the currently known families and about 66% of the known genera. Taxonomic studies on the siphonostomatoids also provide information about their morphology, biology, habitat preference and host association, as well as the distribution of species and their associated host taxa. Molecular analysis, especially sequencing, provides additional information on the existence of cryptic species and population structure, but has high financial costs and a very low success rate in DNA isolation and PCR amplification. Reported declines in abundance of piscivorous fish species, for example, as a result of fishing pressure, with possible synergistic effects of environmental changes, and also the reported potential effects of anthropogenic and climate change on the broader coastal biota, may result in the loss of siphonostomatoid species before they can be described. Furthermore, in South Africa, there is a lack of professional taxonomists to study poorly known groups and this situation will not improve while research emphasis remains on commercially important groups and while taxonomic studies are not recognised for their value in research programmes.  相似文献   

10.
This article discusses how the Chinese seafood industry will affect the rest of the world's fishing industries. The analysis is based on theories of economic comparative advantage, the international division of labour and the internationalization process related to trade activities. Given the increasing domestic demand for fish in China, the limited availability of domestic fish stocks and less success for farmed marine fish in China are considered some of the most important factors in restricting the growth in Chinese seafood production. The necessity of raw fish imports into China may increase pressure on global fish stocks and international fish prices, resulting in tighter supplies worldwide and higher seafood prices for the Chinese. Sustainable fish harvests and trade require stronger fishery management, in particular in the relations between seafood companies and governments along the entire international value chain supplying China. Such structural changes may allow new value-added possibilities for fish farming and the upgrading of certain fish species for human consumption that were previously utilized purely for fish feed.  相似文献   

11.
海洋经济发展是海洋强国战略目标实现的关键内容,为海洋强国建设提供基础动力。文章运用时变随机前沿引力模型和贸易指数分析法,计算出口贸易拓展空间（TS）和海洋高科技产品进口依赖度（IRCA）两项指标,结合波士顿矩阵分析法研究中国在RCEP自贸区内海洋高科技产业出口贸易前景。研究结果表明,中国与RCEP成员国的海洋高科技产品贸易前景光明,有较大贸易拓展空间,但是在不同海洋高科技产品细分市场上的具体情况存在较大差异。此外随机前沿引力模型结果表明,整体而言中国经济规模以及RCEP自贸区其他成员国经济规模对中国海洋高科技产品出口贸易存在显著促进作用。RCEP正式生效后将为中国海洋高科技产品贸易带来战略机遇,中国应采取相应措施,提升国内海洋产品产业和企业竞争力,扩大中国海洋产业尤其是海洋高科技产业贸易,大力提升我国海洋经济强国能力,积极寻求我国海洋经济强国道路。  相似文献   

12.
Marine protected areas (MPAs) could be useful as fisheries management tools for the exportation of pelagic eggs, larvae and adult fish. A decreasing gradient of fish biomass across MPAs boundary may indicate export. We determine whether gradients of decreasing biomass of fish assemblage occurred in Tabarca Marine Reserve over two habitats with different continuity across the boundaries, to test if the patchy nature of the marine environment might act as a barrier for the fish export. In general, significant decreasing gradients in total fish biomass and biomass of some species were observed on P. oceanica and rocky substrates, independently of their different continuity through the reserve boundaries. Changes in the multivariate structure of the fish assemblage were correlated with the distance from integral reserve. All of these results support the hypothesis that the exportation of adult fish from Tabarca Marine Reserve occurs, and this process may influence the surrounding fished areas.  相似文献   

13.
长江口张网鱼类群落结构特征及月相变化   总被引：2，自引：0，他引：2  
为了解长江口鱼类群落结构的现状及变化特征,用张网作业对长江口2010年5月至2011年4月12个月鱼类群落进行了调查。结果1周年共记录56种鱼类,以鲈形目(27种)和鲱形目(10种)种类数目最多。鱼类区系为典型的亚热带动物区系,只出现暖水种(25种)及暖温种(31种)2种适温类型。鱼类种类数目以底栖鱼类(26种)和中上层鱼类占多数(21种),底层鱼类数目较少(9种)。丰度或生物量均由少数几种鱼类占优势。根据鱼类生态类群,海洋洄游性鱼类及河口性鱼类占据种类数目的主要地位,而生物量或丰度均由海洋洄游性鱼类占据主导。每网平均种类数目的最大值和最小值分别出现在7月(18.3种)和1月(7.2种),每网丰度最大值和最小值出现在11月(2 272尾/网)和1月(71尾/网),生物量的最大值出现在9月(11 892g/网),最小值出现在1月(351g/网),而主要种类丰度的时间分布差异也较大;基于丰度计算的Shannon-Wiener多样性指数及Simpson优势度集中指数在时间上也有较大差异,NMDS非度量多维尺度分析显示根据相似性鱼类群落在时间上可分为4组,相邻月一般相似性较近,但2010年12月和2011年1月相似性较小。此外,多元回归分析表明,在径流量、盐度及水温3个环境因素中,引起张网鱼类群落丰度时间变化的主要影响因素是水温。鉴于当前长江口张网捕捞努力量有增加趋势,为保护长江口鱼类群落,需要控制过高的捕捞努力量。  相似文献   

14.
In 1998, in order to combat the degradation of yellow tang populations on the west coast of Hawaii Island, fish replenishment areas (FRAs) were established prohibiting aquarium fishing along more than thirty percent of the coastline. Unlike other marine management approaches in Hawaii, which have largely been controversial, fraught with confusion over regulations, inadequately enforced, and lacking public support, these FRAs have been lauded as a marine conservation success, with wide-ranging support and evidence of rapid replenishment of the yellow tang population. In order to better understand the contextual factors contributing to the success of the West Hawaii FRAs, this research explores the following questions: (1) What factors documented in the literature on marine protected areas (MPAs) have been demonstrated to contribute to or inhibit MPA success internationally; (2) which of these factors do the FRAs of West Hawaii exhibit; and (3) are there additional factors that may have contributed to their wide acceptance and success? Common factors contributing to MPA success are determined through a synthesis of the literature. These include: level of community engagement, socioeconomic characteristics, ecological factors, MPA design, governance, and enforcement. The outcomes of West Hawaii′s FRAs are examined in the context of these factors. While the common factors agreed upon in the literature were key to the success of the FRAs, additional contextual factors such as the unique nature of the aquarium fishery and its social marginalization also played a vital role.  相似文献   

15.
As a result of the stagnation of commercial fishery landings, aquaculture activities are expected to increase over the next decades to match the growing demand for marine protein. Overall, it is expected that the aquaculture sector could reduce some of the fishing pressure applied to wild stocks. However, this development is likely to be limited by the availability of key aquaculture inputs, specifically fishmeal and fish oil products (FMFOP). Aquaculture provided 60 % (fish meal) and 80 % (fish oil) of the world total consumption of these products in 2007. FMFOP are generally derived from small pelagic fish species, but can also be derived from other sources. Identifying the origin of FMFOP is crucial to understanding the effects of this new pressure on marine social-ecological systems. Two factors are of particular importance in the reduction sector transforming wild fish into fishmeal or fish oil: the two “conversion ratios” (i.e. the ratio between the quantity of wild fish harvested and the resulting quantity of FMFOP, and the ratio between the quantity of FMFOP and aquaculture production), and the type of raw material used by the reduction sector. Based on trade and production databases from FAO and the International Fishmeal and Fish oil Organisation (IFFO), this paper proposes an approach to identify the origin of FMFOP. It shows that whereas different countries use different pelagic resources to produce FMFOP, other countries use non-pelagic sources, and some countries use pelagic resources for human consumption.  相似文献   

16.
Estimations of biodiversity and species richness in deep-sea marine ecosystems are impeded by time-consuming methods of species identification. In conservation biology, in environmental monitoring, and in paleontology, a higher-taxon approach (e.g., identification to genera or families) can be used as a surrogate for species richness. We applied a higher-taxon approach to well-documented chemosynthetic communities associated with seep and vent mussel beds to test its applicability in these systems. Significant positive correlations between cumulative number of species and cumulative number of higher taxa were found at the generic, family, and order levels. The number of these higher taxa can be used to predict species richness in vent and seep mussel beds.  相似文献   

17.
Marine protected areas (MPAs) could be useful as fisheries management tools for the exportation of pelagic eggs, larvae and adult fish. A decreasing gradient of fish biomass across MPAs boundary may indicate export. We determine whether gradients of decreasing biomass of fish assemblage occurred in Tabarca Marine Reserve over two habitats with different continuity across the boundaries, to test if the patchy nature of the marine environment might act as a barrier for the fish export. In general, significant decreasing gradients in total fish biomass and biomass of some species were observed on P. oceanica and rocky substrates, independently of their different continuity through the reserve boundaries. Changes in the multivariate structure of the fish assemblage were correlated with the distance from integral reserve. All of these results support the hypothesis that the exportation of adult fish from Tabarca Marine Reserve occurs, and this process may influence the surrounding fished areas.  相似文献   

18.
The conservation status of New Zealand (NZ) marine mammals (suborders Cetacea and Pinnipedia) is reappraised using the 2008 version of the NZ Threat Classification System. The list comprises 56 taxa (named species or subspecies, and as yet unnamed forms or types) in the following categories: Threatened—eight taxa (five Nationally Critical and three Nationally Endangered); Vagrant—six taxa; Migrant—20 taxa; and Data Deficient—13 taxa. A further nine taxa are listed as Not Threatened. Relative to the previous listing, the threat status of two species worsened: the NZ sea lion (Phocarctos hookeri) was uplisted to Nationally Critical and the bottlenose dolphin (Tursiops truncatus) was uplisted to Nationally Endangered. No species was considered to have an improved status. With the uplisting of the NZ sea lion and the continued listing of the Hector's dolphin (Cephalorhynchus hectori hectori) as Endangered and Maui's dolphin (C. hectori maui) as Nationally Critical, all three endemic NZ marine mammals are now considered threatened with extinction. We considered future research or management actions that would allow the downlisting of the eight taxa currently listed as Threatened.  相似文献   

19.
Dispersal, Genetic Differentiation and Speciation in Estuarine Organisms   总被引：1，自引：0，他引：1  
For some of their occupants, estuaries represent spatially discrete habitats, isolated from each other by barriers to dispersal or physiological tolerance. We present contrasting strategies for the retention or export of larvae from their estuary of origin, and consider the implications these have on population structure and divergence. Reported patterns of genetic differentiation and inferred gene flow in estuarine taxa (principally animals) are reviewed, and difficulties in the interpretation of existing genetic data discussed. Species concepts and models of speciation relevant to estuaries are outlined, and patterns of speciation of estuarine taxa reviewed. It is concluded that estuarine environments tend to restrict gene flow and impose distinct selective regimes, generating physiologically adapted populations divergent from their marine counterparts, and the potential for in situ speciation in complete or partial isolation. The resulting taxa may represent sibling or cryptic species groups of truly estuarine origin, rather than simply estuarine populations of marine eurytopes.  相似文献   

20.
海洋生物DNA条形码研究现状与展望   总被引：5，自引：1，他引：4  
海洋生物种类多样,分布广泛,具有复杂性、多样性和趋同性等特点,为了对物种进行更快速、准确地鉴定,急需在传统形态分类学基础上,建立并结合便捷准确的分子鉴定手段。DNA条形码提供了可信息化的分类标准和有效的分类学手段,已成为近年来分类学与生物多样性研究中重要的技术依托。本文概述了DNA条形码当前的发展现状与趋势,并介绍了DNA条形码技术在主要海洋浮游植物(红藻、褐藻、绿藻、硅藻、甲藻)、无脊椎动物(海绵动物、刺胞动物、甲壳动物和软体动物等)和鱼类中的研究进展,以及不同条形码基因针对于不同生物类群的有效性和适用性,指出了目前条形码技术在各海洋类群中存在的主要问题,并对未来的相关工作做了展望,希望为今后我国的海洋生物DNA条形码研究提供理论基础。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号