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1.
The 1992 United Nations Conference on Environment and Development (UNCED) held at Rio de Janeiro was a seminal event that addressed the interplay of economic development and human use of natural resources with the need for protection of the natural environment. The general principles embodied in the Rio Declaration and the provisions included in the comprehensive Agenda 21 expressed the expectations of the international community and set the stage for national and international policy and legal developments in a host of different areas, including the governance of the ocean's living resources. Chapter 17 of Agenda 21 focused on the world's oceans and seas and crystallized growing world community concern with problems such as unregulated fishing, fishing vessel reflagging, overcapitalization of the fishing industry, inadequate fisheries enforcement, and insufficient cooperation among states. Further, the documentation of UNCED evidenced interest in new governance frameworks and concepts such as ecosystem-based management and precaution. In retrospect, it is clear that the ideas discussed at Rio have been important and have been implemented by a variety of governments and international organizations as they exercise their responsibilities for fisheries management. This article examines the principles and approaches suggested by UNCED as they relate to world fisheries and considers how they have been reflected in global fishery agreements such as the FAO Compliance Agreement and the United Nations Fish Stocks Agreement, in the work of international fishery bodies such as the FAO Committee on Fisheries, and in the efforts of a number of regional fishery commissions. It also addresses the significance and ramifications of changes suggested by Agenda 21 for the future conduct and management of world marine fisheries.  相似文献   

2.
The biology of elasmobranchs makes them very vulnerable to fishing pressure and there is increasing international concern over their exploitation. In northern Australia the stocks of some species may be shared with those in southern Indonesia. Indonesia has the highest landings of elasmobranchs worldwide (>100,000 t p.a.) and millions of Indonesian artisanal fishers rely heavily on elasmobranchs taken in target fisheries. They are also taken by industrial trawlers and as bycatch in pelagic tuna fisheries. This paper, resulting from a collaborative project between Australia and Indonesia, summarises the elasmobranch fisheries; the characteristics of the fisheries are outlined, the status of the stocks are assessed, and management options described and discussed. The project focussed on representative markets and fish landing sites in southern Indonesia from 2001 to 2005. Data were from market surveys, the records of the Indonesian Directorate General of Capture Fisheries, and from research cruises. Data from the ongoing tuna monitoring programme showed that shark bycatch from the tuna fleets forms about 11% of shark landings in Indonesia. Yield per recruit and related analyses were used to integrate biological information to indicate the productivity of each species to allow for management policy options and constraints. Research cruise data show that catch rates of elasmobranchs in the Java Sea declined by at least one order of magnitude between 1976 and 1997. The results indicate strongly that many of the shark and ray species in Indonesia are overfished and that the most effective management strategy may need to involve capacity control, such as licencing, gear restrictions and catch limits, together with controls on the fin trade.  相似文献   

3.
This article considers how international management of fisheries under the 1995 UN Fish Stocks Agreement and regional fisheries management organizations is affected by one of the basic principles of the law of treaties: the rule pacta tertiis nec nocent nec prosunt, by which international fisheries regulations as treaty-based obligations bind only the parties to the treaty concerned and not third states without their consent. It is shown that the relatively recent concept of IUU (illegal, unreported, and unregulated) fishing, often seen as a way to circumvent this problem, is flawed as a solution, largely because the leading global and European Union instruments in which it is embodied in effect equate unregulated fishing with illegal fishing in a way that pays insufficient heed to the constraints of the pacta tertiis rule.  相似文献   

4.
Both fisheries exploitation and increased nutrient loadings strongly affect fish and shellfish abundance and production in estuaries. These stressors do not act independently; instead, they jointly influence food webs, and each affects the sensitivity of species and ecosystems to the other. Nutrient enrichment and the habitat degradation it sometimes causes can affect sustainable yields of fisheries, and fisheries exploitation can affect the ability of estuarine systems to process nutrients. The total biomass of fisheries landings in estuaries and semi-enclosed seas tends to increase with nitrogen loadings in spite of hypoxia, but hypoxia and other negative effects of nutrient over-enrichment cause declines in individual species and in parts of systems most severely affected. More thoroughly integrated management of nutrients and fisheries will permit more effective management responses to systems affected by both stressors, including the application of fisheries regulations to rebuild stocks negatively affected by eutrophication. Reducing fishing mortality may lead to the recovery of depressed populations even when eutrophication contributes to population declines if actions are taken while the population retains sufficient reproductive potential. New advances in modeling, statistics, and technology promise to provide the information needed to improve the understanding and management of systems subject to both nutrient enrichment and fisheries exploitation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Guest editors: J. H. Andersen & D. J. Conley Eutrophication in Coastal Ecosystems: Selected papers from the Second International Symposium on Research and Management of Eutrophication in Coastal Ecosystems, 20–23 June 2006, Nyborg, Denmark  相似文献   

5.
Synopsis The biological diversity and productivity of Philippine coral reefs are threatened by siltation, destructive fishing methods, coral and shell collecting and overfishing. Destructive fishing includes: the widespread, illegal use of explosives; poisons such as sodium cyanide; muro-ami and kayakas fishing; and trawling. The recent decline in catch rates threatens the livelihood of 700 000 near-shore subsistence fishermen who catch 55% of the total landings. The new government under Corazon Aquino wishes to protect the marine environment through the creation of a viable marine conservation management plan, enforcement of existing laws and through cooperation between government, non-government and international agencies to provide education and research. The Department of Agriculture, which has the authority for fisheries, has designated the International Marinelife Alliance as the lead non-government agency involved with fund raising, net-training and finding alternatives to destructive fishing methods.This essay addresses the societal relationships of village fishery to government, aid organizations, and science. Vadim Vladykov always maintained close relationship with fishermen and devoted over a year of his life to helping develop fisheries in Iran.  相似文献   

6.
The past stormy fisheries relations between Canada and the European Union, in particular with Spain, has been replaced by uncertainty in the application of the newly amended Northwest Atlantic Fisheries Convention. These issues are addressed in this article that sheds light on the more peaceful fishing relations between the two leading international actors in this area of the oceans.  相似文献   

7.
The designation of Marine Protected Areas (MPAs) in Indonesia has been accelerated over the past two decades in line with international biodiversity conservation commitments and to secure a basis for decentralised fisheries resources management. The Berau MPA of northeast Kalimantan is one of them. This paper shows how the establishment of the park boundaries and zoning affects local fishers' livelihoods. Particular attention is paid to the position of outsider fishers or andon, who have a legal right to access the resource rich fishing grounds. Decentralised district government legitimises outsider fisheries activities because andon fishing permits bring in fees as a contribution to the regional income (PAD or pendapatan asli daerah), while international environmental organisations and local fishers regard the outsider fishers as illegitimately entering the MPA to access resources they regard as their own. Thus, MPA boundaries appear to be highly permeable, with both local fishers and environmental NGOs seeing the presence of andon as illegitimate and illicit, despite being legal.  相似文献   

8.
Regional fishery organizations are increasingly being viewed as "vehicles of good governance" created to secure the sustainable development of international fisheries. These political expectations have not been followed by analytical refinement of how to explain and understand their formation, roles, objectives, institutional setups, or efficiency. This article provides a conceptual discussion of regional fishery organizations and introduces an organizational typology as a basis for their study. Thus, an analytical distinction is made between regional fisheries management organizations, regional coordination and development organizations and scientific research organizations. This typology and the evolution of the Law of the Sea, from an open access to the exclusive economic zone regime, are used to analyze the institutional arrangements of regional fishery organizations.  相似文献   

9.
In March 1995, Canadian fisheries authorities boarded and arrested the Spanish fishing vessel, Estai, outside the Canadian 200‐mile zone on the Grand Banks, an event that served to focus world attention on a dispute that had its origins in the failure of the 1982 United Nations Convention on the Law of the Sea to implement an effective conservation and management regime for fish stocks on the high seas, particularly with respect to fish stocks that straddle coastal states’ exclusive economic zones. This article examines the origins of the dispute, including the allegations relating to overfishing of North Atlantic Fisheries Organization‐recommended quotas, the background to the vessel's arrest, and the subsequent confrontation that occurred, both at diplomatic levels and on the high seas, between Canada and the European Union. An analysis is made of the case in international law for Canada's extension of jurisdiction beyond 200 miles pursuant to the provisions of Section 5 of the Coastal Fisheries Protection Act. Finally, the article examines the implications of the recently concluded Agreement on the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks for disputes of the kind that arose in the present case.  相似文献   

10.
在我国,鱼类养殖是一项重要的商业活动。鱼类养殖在过去几十年的快速发展过程中,对水环境产生了重要影响。研究表明:鱼类养殖对养殖区鱼、浮游生物、水生植物群落结构和水质变化有重要影响。现在,几乎所有的鱼类养殖系统都在一定程度上受到了损害。随着人们环境保护意识的增强,鱼类养殖的环境效应和渔业管理问题已引起了社会的广泛关注,渔业管理不再仅仅是通过开发资源以获取最高产量。面临挑战,人们应该采取切实可行的步骤,从传统的渔业管理转变到基于生态系统的渔业管理,将渔业纳入生态系统管理以保障养殖业的可持续发展。  相似文献   

11.
Fisheries exploitation represents a considerable threat to coral reef fish resources because even modest levels of extraction can alter ecological dynamics via shifts of stock size, species composition, and size-structure of the fish assemblage. Although species occupying higher trophic groups are known to suffer the majority of exploitative effects, changes in composition among lower trophic groups may be major, though are not frequently explored. Using size-based biomass spectrum analysis, we investigate the effects of fishing on the size-structure of coral reef fish assemblages spanning four geopolitical regions and determine if patterns of exploitation vary across trophic groups. Our analyses reveal striking evidence for the variety of effects fisheries exploitation can have on coral reef fish assemblages. When examining biomass spectra across the entire fish assemblage we found consistent evidence of size-specific exploitation, in which large-bodied individuals experience disproportionate reductions. The pattern was paralleled by and likely driven by, strongly size-specific reductions among top predators. In contrast, evidence of exploitation patterns was variable among lower trophic groups, in many cases including evidence of reductions across all size classes. The breadth of size classes and trophic groups that showed evidence of exploitation related positively to local human population density and diversity of fishing methods employed. Our findings highlight the complexity of coral reef fisheries and that the effects of exploitation on coral reefs can be realized throughout the entire fish assemblage, across multiple trophic groups and not solely restricted to large-bodied top-predators. Size-specific changes among fishes of lower trophic groups likely lead to altered ecological functioning of heavily exploited coral reefs. Together these findings reinforce the value of taking a multi-trophic group approach to monitoring and managing coral reef fisheries.  相似文献   

12.
Japanese negotiators agreed to eliminate driftnet fishing for salmon in the North Pacific Ocean by the end of 1992. The Japanese high seas fishing fleet for salmon had been an economically valuable yet environmentally destructive operation for four decades. The Japanese government progressively phased out lucrative Japanese salmon fishing operations in the North Pacific, apparently capitulating to U.S. pressure. No U.S. enforcement with punitive sanctions proved necessary, however. Specific characteristics of the international market created the possibility of an environmentally benign international agreement. International integration of the market for fisheries products was made possible by the high market value of salmon in the United States and in Japan. In the 1970s, foreign direct investment from vertically integrated, Tokyo‐based fishing firms into canning and processing operations in Alaska and the Pacific Northwest facilitated U.S. Japanese agreement. The high existence (nonuse) value of marine mammals in the United States was also an important factor.  相似文献   

13.
Fisheries bioeconomics: why is it so widely misunderstood?   总被引:1,自引:0,他引:1  
Many fisheries management systems, even when based on apparently sound science, have failed to prevent severe overfishing. And even when successful in this sense, such systems have frequently resulted in a large degree of excess fishing capacity. The reason for these failures can often be found in a lack of consideration of the economic incentives affecting fishermen. Specifically, when forced to compete for a fixed total annual catch quota (TAC), fishermen are motivated to fish at high intensity, and to expand the fishing power of their vessels. Individual fishing quotas (IFQs) are being increasingly used as a method of altering economic incentives in a desirable way. IFQ systems, however, can also suffer severe shortcomings, unless substantial fees are extracted for the exclusive right to exploit a publicly owned resource. When combined with appropriate fees, or royalties, IFQs can indeed result in sustainable, profitable fisheries. There still remains the fundamental question of risk management, but this is also now beginning to be addressed. Thus there is now a strong hope for the future success of marine fisheries, at least within 200-mile coastal zones.  相似文献   

14.
The paper describes factors influencing artisanal fisheries at the São Francisco River in Brazil as an example of the challenges of managing socially and economically valued common-pool resource systems. A rapid assessment of problems affecting São Francisco River fisheries in 10 communities was carried out in 2003, representing the upper, middle, and lower river portions. Field visits, interviews, focus group discussions and a literature survey allowed us to map socioeconomic and environmental factors important to the fisheries, including conflicts and tensions between stakeholders. Federal, state, and municipal governments, industries, farmers, hydroelectric companies, and urban and rural populations all have a stake in river use. Traditional fishers are the most disadvantaged of these stakeholders. With declining fish populations, most of the fishing communities surveyed are now poor, socially excluded, and with few alternative livelihood options. The stakeholders involved in access and use conflicts are artisanal fishers, professional fishers, sport fishers, farmers, enforcement and regulatory agencies, and hydroelectric companies. Traditional fishers have close ties to the river and its environment and they are usually not invited to contribute to resource management decisions. We recommend changes to management structures involving the fishing communities that are essential to resolve the major conflicts and to improve equity and sustainability of artisanal fisheries.  相似文献   

15.
This paper examines the ecological and biological status of fisheries in three coastal lagoons in the southern Mediterranean region: Merja Zerga in Morocco, Ghar El Melh in Tunisia and Lake Manzala in Egypt. Despite similarities in some ecological characteristics, the three lagoons’ respective fisheries show differences in specific composition, in population structure and in their production both in qualitative and quantitative aspects. Thus, in Merja Zerga and Ghar El Melh the fish fauna shows a marine affinity where grey mullet and eels dominate the fish production. In Lake Manzala the ichthyofauna displays a more freshwater affinity with tilapia the dominant group of species. Otherwise, overall fish production at the three sites is regulated by variations in fishing activities, local environments and seasonal conditions. A decrease in fish production was noted over recent years and this is attributed to deteriorating ecological conditions. A variety of factors are implicated including sea communication problems, reduction of the continental (fresh) water supply and increase of pollution causing eutrophication. In addition, over fishing with a continuing increase of fishing effort units, contributes to fisheries decline. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Guest editors: J. R. Thompson & R. J. Flower Hydro-ecological Monitoring and Modelling of North African Coastal Lagoons  相似文献   

16.
A key challenge in contemporary ecology and conservation is the accurate tracking of the spatial distribution of various human impacts, such as fishing. While coastal fisheries in national waters are closely monitored in some countries, existing maps of fishing effort elsewhere are fraught with uncertainty, especially in remote areas and the High Seas. Better understanding of the behavior of the global fishing fleets is required in order to prioritize and enforce fisheries management and conservation measures worldwide. Satellite-based Automatic Information Systems (S-AIS) are now commonly installed on most ocean-going vessels and have been proposed as a novel tool to explore the movements of fishing fleets in near real time. Here we present approaches to identify fishing activity from S-AIS data for three dominant fishing gear types: trawl, longline and purse seine. Using a large dataset containing worldwide fishing vessel tracks from 2011–2015, we developed three methods to detect and map fishing activities: for trawlers we produced a Hidden Markov Model (HMM) using vessel speed as observation variable. For longliners we have designed a Data Mining (DM) approach using an algorithm inspired from studies on animal movement. For purse seiners a multi-layered filtering strategy based on vessel speed and operation time was implemented. Validation against expert-labeled datasets showed average detection accuracies of 83% for trawler and longliner, and 97% for purse seiner. Our study represents the first comprehensive approach to detect and identify potential fishing behavior for three major gear types operating on a global scale. We hope that this work will enable new efforts to assess the spatial and temporal distribution of global fishing effort and make global fisheries activities transparent to ocean scientists, managers and the public.  相似文献   

17.
Underwater acoustics in marine fisheries and fisheries research   总被引:9,自引:0,他引:9  
Underwater acoustics enables the detection and precise location of fish and is therefore a prerequisite for effective fishing methods such as pelagic trawling and purse seining. The application of acoustic instruments to detect fish and monitor gear performance in modern commercial fisheries is outlined. The latest developments in obtaining information such as bottom roughness and determining such characteristics of fish detected as size and species are presented.Echo integration is now widely used to estimate the abundance of commercially important fish stocks. The principles of the method are outlined briefly, and special emphasis is put on such effects of fish behaviour as the dramatic influence of fish orientation on its backscattering cross section, the possible effects of vessel avoidance, and the uncertainties connected with spatial variability.The use of acoustic tags, echosounders and sonar to study and quantify fish behaviour and distribution is outlined, with particular attention to new developments that provide detailed information on fish behaviour and distribution in relation to environmental parameters.Future developments and improvements in the application of underwater acoustics to commercial fisheries and fisheries research are suggested  相似文献   

18.
Artificial reefs have been deployed worldwide for the last three decades in response to problems concerning coastal resources, ecosystems and fisheries. In many countries they have became important elements of integrated fisheries management plans. In Portugal two artificial reef systems (ARSs) were deployed by the Portuguese Institute of Marine Research (IPIMAR) in 1990, in the southern coast (Algarve). They were located off Faro and Olhão, over different sea-bottom types and located at different distances from the coastline. To analyse the effect of ARSs deployment on local fish assemblages and to evaluate their effectiveness in terms of mean fishing yields and mean number of species caught, fishing surveys have been conducted over 14 years (256 net sets) using a gillnet to sample the ARS of Faro and Olhão and respective control sites. The fishing yields from the ARs continually exceeded those from the control sites, in both the mean number of species caught and the mean CPUE in weight (1.8–2.6 times); both were higher at Faro. Moreover, the comparison between fish assemblages from the ARS and respective control sites showed that the deployment of the man-made structures did not change the composition of the fish assemblages caught by the gill nets, or the equilibrium of the community, since the relative proportion of the different functional groups of fish remained stable. The ARSs are a useful management tool on the Algarve coast, enhancing and diversifying the catches, thus contributing to improved local artisanal fisheries, which play a major role in this region.  相似文献   

19.
Status of research on Yangtze fish biology and fisheries   总被引:2,自引:0,他引:2  
The Yangtze is the largest river in China and the third largest river in the world. Being pregnant with plentiful fish resources, it is not only the representative of the areas with biological diversity, but also a cradle of freshwater fisheries in China. In the Yangtze, at present, the fishery resources are seriously depleted; the fishery yield by fishing is significantly reduced; significant changes have occurred on the structure of fish community, with decrease in migratory fish species, reduction in the quantity of the populations of rare, peculiar and economically important fish species and increase in the number of exotic fish species, and severe trend in fish stunting. Habitat fragmentation and shrinkage, resources overexploitation, water pollution and invasion of exotic species are the main causes for threatening fish stocks in the Yangtze River. Since 1950’s, a lot of scientific researches have been conducted on biology of fishes from the Yangtze River and its fisheries to provide scientific basis for their protection. In recent years, measures such as closed spring, fish reserves, artificial enhancement & release, ecological rehabilitation, fishery management and international cooperation have played important roles. Nevertheless, researches on fishes from the Yangtze cannot adequately meet the demand for their protection. Especially, those in the aspects of population ecology of Yangtze fishes, species endangerment mechanism, ecological effects of large hydraulic projects and protection strategy are not deep enough. It is recommended that scientific researches should be conducted in comprehensive survey of Yangtze fish resources, fish endangerment mechanism, techniques in artificial enhancement and release of key species, risk assessment of exotic species, ecological rehabilitation of major fisheries functional zones, etc.  相似文献   

20.
The incorporation of Taiwan into the legal framework of regional fisheries management organisations (RFMOs) has proven to be challenging. This article reviews RFMO practice in this area in light of the recent experience of the Southern Indian Ocean Fisheries Agreement (SIOFA) and outlines some of the legal creativity that has provided solutions. Taiwan's participation in RFMOs is essential to the achievement of effective management outcomes. Accordingly, this article argues that today, with relevant international legal obligations and numerous suitable precedents, political considerations should not represent an obstacle to providing for fair and appropriate involvement of Taiwan in RFMOs.  相似文献   

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