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1.
Vessel monitoring systems (VMS) are considered important instruments for fisheries monitoring, control and surveillance (MCS) to reverse the current depressed state of the world’s fisheries, and have been mandated worldwide by fishery management agencies. The essential function of the system is to provide near-real time vessel position; the potential applications could, however, be more than that. This study explores the additional benefits, with practical examples, that Taiwan has received from implementing the system: in improving the quantity and quality of logbooks recovered, obtaining access to fishery-independent fishing effort estimates and prompt catch/effort reporting, enabling the possibility of regional management and understanding of both fleet dynamics and vessel behavior, and increasing efficiency of vessel safety protection. For other distant-water fishing nations, Taiwan’s experiences serve to demonstrate how the application of VMS technology can advance sustainable fisheries management.  相似文献   

2.
Coastal fisheries are complex ecological and social systems, evolving in time with a shift from commercial towards recreational effort. We describe the coastal fisheries of Mallorca (W Mediterranean) and the management policies implemented to show the challenges faced at regional level to handle the different management tools used to conserve biodiversity and the social fabric in the coastal zone. Our example provides evidence of the complexity of fishing rights and how they can be adapted into practical fisheries management by combining fishing rights, open access recreational fishery, community-based management and biodiversity conservation.  相似文献   

3.
Fisheries statistics provided by the Hellenic Statistical Authority (HELSTAT) have been often criticized for unusual estimates in landings and fishing effort data and for limitations in the sampling methodology, although there is no study on the identification of these biased and misreporting estimates. In the present study the landings per species and fishing subarea, as well as the fishing effort data per fishing gear reported by HELSTAT were analysed over the period 1982–2010. The results showed abrupt changes of both the recorded species and species landings per subarea, spurious correlations of landings among different species groups and misreporting estimates in the number of fishing vessels per fishing gear. These might be likely attributed to: (a) differences of the HELSTAT administrative infrastructures at local scale, (b) changes in the sampling protocol followed by HELSTAT, (c) reporting faults made by HELSTAT, (d) fisheries restrictive measures at local basis, (e) other factors that increased the bias and the uncertainties of HELSTAT fisheries data and related to socio-economic (i.e. fuel price) and operational (i.e. spatial structure of the fisheries fleet) aspects and/or (f) to environmental changes that might possibly affected fisheries dynamics. The present study aims to the improvement of the effectiveness of the national fisheries statistics as pinpointed by Common Fisheries Policy in order to avoid imprecise and/or biased estimations about the state of the fisheries.  相似文献   

4.
There is a paucity of information on subsistence reef fisheries of indigenous communities in Torres Strait, Australia, and its role within their hybrid economy. Bus route surveys and semi-structured interviews were conducted in 2005 and 2006 on three islands in Torres Strait to understand whether subsistence fishing remains important for the livelihoods of Torres Strait communities and whether patterns of fishing effort are driven by changes in their socio-economic structure. Strong interactions among private (commercial fishing and other wage-employment), public (social security payments from the State) and subsistence sectors were observed. When social security payments were spent, Islanders were more reliant on subsistence fishing. Also, higher levels of involvement in the private sector corresponded with a shift from shore to boat-based subsistence activities. Socio-economic factors, such as involvement in commercial fishing and social security payments, were identified as the main driving factors of subsistence fishing activities. Findings of the present study stress the importance of considering socio-economic factors explicitly in future fisheries assessments and management decisions concerning the sustainability of resources in Torres Strait.  相似文献   

5.
As catch and effort statistics including fishing time and location are essential for producing abundance indices for utilized fish stocks, fishing states are encouraged under the FAO Code of Conduct for Responsible Fisheries to collect and maintain such statistics. However, for coastal fisheries (including artisanal fisheries) that are mainly composed of small-sized vessels which are usually too numerous to monitor, fisheries statistics collection systems are often either lacking or of insufficient quality (e.g. incomplete or inaccurate). Vessel monitoring system (VMS) data are commonly used to construct or improve estimation of fishing effort and fishing location in large-scale fisheries. Most coastal fisheries lack VMS but their countries do have coastal surveillance radar systems (CSRS) for security and enforcement purposes. This study illustrates and recommends opportunistic use of CSRS data to provide similar scientific benefits to VMS data for coastal fisheries. CSRS in combination with market landings data can construct logbook-like catch and effort statistics. This study introduces a method and demonstrates its usefulness for scientific research and management purposes, including the potential to obtain a higher accuracy and precision, particularly for fishing location and catch amount. Limitations of the CSRS data and challenges to managers involved in its application are also discussed.  相似文献   

6.
The science and management of marine resources is increasingly grappling with the use of ecosystem-based fisheries management. Though ecosystem-based fisheries management seeks to unite biological and sociocultural concerns into a holistic framework, people are often seen simply as external drivers of change. The technical questions that are often posed, such as the delineation of boundaries or the strategies of governance, are however more broadly questions concerning the social production of nature. This paper explores these issues by analyzing both the spatial fishing practices of different fishermen and the results of a series of workshops held in New England to solicit opinions about ecosystem-based fisheries management. The paper emphasizes teasing apart the human dimensions of fishing embedded in predominant notions such as fishing effort through more explicit consideration of spatially based resource dependencies and mutual constitution of society-nature.  相似文献   

7.
Tropical small-scale fisheries are highly heterogeneous with respect to a wide range of fisheries characteristics, but that heterogeneity has generally not been adequately studied or considered in management. This study investigated fisheries heterogeneity and the extent to which it is accounted for in management regulations in eight small-scale fishing communities located in floodplain ecosystems of the Amazon basin. Analyses of 29,844 fishery landing interview data revealed that fisheries heterogeneity with respect to gear, habitat, species composition, and total catch and fishing effort was high across all communities, but low over the years in the same communities, indicating that each community must be considered as a distinct management unit. Data analyses also revealed that many important community fisheries characteristics were not accounted for by government- and community-based management regulations. Total catch and fishing effort were largely unregulated; there were no size or closed season limits for one-third of the most important fishery species; and the nursery habitats used by most fishery species were not protected in any fashion. Clearly, increased attention to cross-community fisheries heterogeneity can improve the design and implementation of management regulations. The management problems created by the heterogeneity of small-scale fisheries are discussed, and the potential of the “barefoot ecologist” concept to address them is considered.  相似文献   

8.
捕捞作用下鱼类资源量变动短期影响的模拟研究   总被引:1,自引:0,他引:1  
持续高强度的捕捞已经严重影响到渔业资源的可持续利用,其对渔业资源的最直接和明显的影响就是资源量的减少.本文对不同捕捞强度作用下,不同生活史和补充量的单鱼种群体的资源量在短期内(1~3a)的变动进行了模拟研究.结果表明,受捕捞影响,鱼类群体资源量在周年内适渐减少,但短寿命种类的资源量比寿命较长的种类更易恢复.年补充量和捕...  相似文献   

9.
In order to avoid conflicts when spatially explicit rules are implemented, it is critical to understand the spatial distribution of fishing effort, the migration patterns of fishermen and the use of temporary fishing camps. The migration of fishermen is a process shaped by historical patterns of resource availability, in addition to economic and political factors. We present an example in which a temporary fishing camp used for extraction of benthic resources (Loco: Concholepas concholepas) changed into a permanent one during the study period. Throughout the study period fishing effort (trips) was closely related to the productivity of the different fishing grounds, with more trips directed to the most productive areas. The conversion from a temporary to a permanent fishing camp did not improve the efficiency of the loco fishery, but did allow better access to alternative resources (surf clams) on nearby fishing grounds. The succession from simple shelters to a permanent ‘caleta’ is a common situation along the Chilean coast, motivated originally by resource availability and more recently by the creation of the TURF system. In particular the TURF system converts temporary (resource driven) movements of fishermen into rigid stationary caletas, which creates a number of problems. Temporary fishing camps are common when fishing grounds are far from the base port, but they require specific administrative tools in order to achieve sustainable fisheries management.  相似文献   

10.
11.
Understanding the economic value of ocean space is critical for implementing marine spatial planning (MSP). Empirical data from 1999 to 2008 are compiled on the economic values arising from commercial fishing in the Gulf of Maine and adjacent areas. The data are analyzed to characterize factors affecting the spatial and temporal distribution of measures of economic productivity and fishing effort. The analysis consisted of four components: (1) estimation of net revenue at the 10-min square level by season and gear; (2) assessment of variability for catch revenue and catch per unit effort; (3) mapping net revenue and variability in the study area; and (4) estimation of interactions among catch, effort, season, and gear type. The results indicated that, at each location, average fishing efforts exhibited a positive response to increases in expected revenues and a negative response to variability in revenues. Most of the variability in catch revenue can be explained by changes in fishing effort, implying that the spatial patterns of fishery resources are relatively stable at the 10-min square level. An important conclusion is that a spatial scale of at least the 10-min square is appropriate for undertaking MSP involving allocations of commercial fisheries.  相似文献   

12.
Fisheries management in European waters is gradually moving from a single-species perspective towards a more holistic ecosystem approach to management (EAM), acknowledging the need to take all ecosystem components into account. Prerequisite within an EAM is the need for management processes that directly influence the ecological effects of fishing, such as the mortality of target and non-target species. Up until recently, placing limits on the quantities of fish that can be landed, through the imposition of annual total allowable catches (TACs) for the target species, has been the principal management mechanism employed. However, pressure on non-target components of marine ecosystems is more closely linked to prevailing levels of fishing activity, so only if TACs are closely related to subsequent fishing effort will TAC management serve to control the broader ecosystem impacts of fishing. We show that in the mixed fisheries that characterise the North Sea, the linkage between variation in TAC and the resulting fishing effort is in fact generally weak. Reliance solely on TACs to regulate fishing activity is therefore unlikely to mitigate the impacts of fishing on non-target species. Consequently, we conclude that the relationship between TACs and effort is insufficient for TACs to be used as the principal management tool within an EAM. The implications, and some alternatives, for fisheries management are discussed.  相似文献   

13.
It is widely recognized that fishing states are obliged to exercise flag state responsibility over their vessels. In an attempt to become a responsible fishing actor, Taiwan has endeavored to manage its distant water fishing fleet in accordance with international fisheries management. However, the long-standing problems of illegal, unreported and unregulated (IUU) fishing, fish laundering, and fishing overcapacity, which remained unsolved during the 1990s and early 2000s, brought its management capability into doubt. Failure to address these problems undermined the credibility of all management measures and ultimately resulted in a recommendation adopted by International Commission for the Conservation of the Atlantic Tunas (ICCAT) in 2005. This recommendation significantly affected Taiwan's distant water fishing policy. This paper examines how Taiwan assimilated this outside force into its fishing policy as a new response to international fisheries management and how fishers perceived this response. It shows that Taiwan's efforts in controlling distant water fisheries marked a big change, specifically manifest in three noticeable actions - reducing excessive bigeye-targeted efforts, deterring IUU fishing, and strengthening fisheries management. The study advises that management of small tuna vessels be effectively exercised and recommends future actions on providing subsidies for fishers to partially offset costs incurred by rule compliance, streamlining their administrative work, enhancing communication with them, putting more enforcement and meaningful penalties in place. Finally, the study indicates the existence of an interaction in the international fisheries management scheme, potentially favoring Taiwan to bargain for fishing rights and a favorable status in the participation of regional fisheries management organizations (RFMOs) in the future if it continues to exercise effective control of distant water fisheries.  相似文献   

14.
Stock assessments of quota or effort managed fisheries in which the duration of the fishing season is 12 months are invariably delivered well into the subsequent fishing season. As a result, quotas are frequently based on year-old data. This delay is often unavoidable because it may take months to collect, collate and analyse data necessary to assess fishery performance. The South Australian fisheries for blacklip (Haliotis rubra Leach, 1814) and greenlip abalone (H. laevigata Donovan, 1808) have addressed this issue by using provisional data on current stock status to inform application of the harvest strategy decision rules that set the quota for the next year. The primary index of relative abundance for these fisheries is catch per unit effort (CPUE). Our study uses 25 years (1988–2012) of CPUE data to quantify the differences between the provisional and complete-season CPUE estimates at the spatial scales used to assess the fisheries. We demonstrate that, in most cases, there was a strong relationship between the provisional and complete-season CPUE estimates for both species, with little evidence of bias. As the provisional CPUE estimates were a reliable and accurate predictor of the complete-season CPUE estimates, this provides a high degree of confidence in using provisional CPUE estimates to set quotas, thereby overcoming the difficulty of basing decisions on aged data. These findings are likely to be applicable to other fisheries, particularly those where much of the annual catch is obtained (or effort expended) in a short time period at the commencement of the fishing season.  相似文献   

15.
The Galapagos Islands are a prime example of a place where fishery management policies have been established without first understanding the behavior of fishermen. Since the creation of the Galapagos Marine Reserve in 1998, there has not been a single study in the archipelago that investigates fishing behavior and the factors affecting this behavior. This paper addresses this gap in the literature by describing and analyzing the decisions of the fishing fleet for the red spiny lobster fishery. It focuses on factors that affect the short-term decisions regarding both participation and intensity of participation in the lobster fishery. This paper finds that the fishing fleet in the Galapagos Islands behaves as profit maximizing firms, because they consider all the benefits and costs that affect both their participation decision as well as their decision about how frequently to be active after they have decided to participate. The results also show that there is a large latent effort in the lobster fisheries that could threaten the sustainability of any initiatives aimed at increasing catchability, prices, or markets. It is expected that this analysis will be valuable to policy makers when designing or improving the management plans for Galapagos fisheries.  相似文献   

16.
The aim of this paper is to compare the criteria for eco-labeling of wild-caught fish in the Norwegian eco-certified fisheries, and to study if these eco-labels affect the harvesting patterns of Norwegian fishermen. The eco-labels Marine Stewardship Council (MSC), KRAV and Friend of the Sea (FOS) as applied in 2009 were studied. In this study, the harvesting patterns are defined by using the following parameters: season, catch area, size of fishing vessel, gear type, bycatch, location of landing site and distance to the fishing ground. KRAV had more specific criteria than did MSC and FOS in specific fisheries regarding time of the fishing effort, catch area, size of fishing vessels, gear type (e.g. hook size, and the use of beam trawlers was not permitted) and distance to the fishing ground. The findings show that few of the eco-label requirements influenced these aspects in Norwegian fisheries.  相似文献   

17.
This article investigates practical aspects and limitations of various fishery management techniques. Restrictions on catch and fishing effort (active regulations) are described, and the authors point out that catch restrictions are less robust scientifically than effort restrictions. Spatial — temporal restrictions, gear restrictions, and restrictions on the nature of the catch-which are passive with respect to fishing mortality-are reviewed and it is concluded that fishing mortality is theoretically unbounded when only passive methods of fisheries management are applied.  相似文献   

18.
Assessment of IUU fishing for Southern Bluefin Tuna   总被引:1,自引:0,他引:1  
Illegal, unreported and unregulated (IUU) fishing is recognized as one of the largest threats to the sustainability of the world's fisheries. This paper focuses on IUU fishing in the context of unreported catches by members or co-operating non-members of regional fisheries management organizations (RFMOs) and their implications for scientific assessments of stock status and management advice. A review of Japanese market statistics was undertaken in 2006 by an independent panel in relation to catches of southern bluefin tuna (SBT). Based on this review, the Commission for the Conservation of Southern Bluefin Tuna (CCSBT) concluded that very substantial and continuous unreported catches of SBT had been taken by longline vessels since at least the early 1990s. While uncertainty exists about the fleets contributing to these IUU catches, the assumption used within the CCSBT Scientific Committee is that a significant proportion of these were taken by Japanese longliners. Implications of these unreported catches for the stock assessments by RFMOs are discussed in light of the central role that Japanese vessel reported data have in the assessment of the world's tuna and billfish stocks. Results indicate that it is plausible that the unreported catches of SBT stem from the misreporting of catches as other tuna species and/or the location of fishing effort. The magnitude and extended period of the unreported SBT catches highlight the wide-spread risks of relying on fishery dependent logbook data in the absence of verification. An urgent need exists for minimum standards of verification of catch, effort and landing statistics for use in scientific assessments. The fisheries science community needs to be more pro-active in the development of such standards and the implementation of independent monitoring and verification. In addition, there is a need to reform the operation of the scientific bodies of RFMOs in terms of transparency, the treatment of uncertainty and the burden of proof if they are to be effective in providing objective scientific advice consistent with the intent of international agreements.  相似文献   

19.
Information on the cost of fishing is integral in measuring fisheries performance and correctly evaluating the economic impacts of fisheries regulations and management rules. However, limited availability of cost data often renders such analyses either incomplete or implausible. This study discusses a survey effort that was undertaken in the Northeast US to collect fisheries annual fixed cost data directly from commercial fishermen. Stratified random samples of fishing vessel owners were surveyed in 2012 and 2013. An overview of the survey procedures, sample selection and administration is given here. The data cleaning process, non-response bias and data summaries are also presented. A modeling framework is discussed for estimating fisheries cost data. Robust cost models in combination with regular data collection efforts will allow for more complete economic and financial analyses relevant to fisheries management and conservation.  相似文献   

20.
Managing marine fisheries using output controls in the form of individual transferable quotas (ITQs) can be an attractive alternative to more traditional input controls. There are now a number of examples of where ITQ-managed fisheries have been able to reduce the impact of the major management problems in global fisheries, namely, gross over-capitalisation and effort. However, ITQs are not the perfect management tool and one of the lesser known consequences of ITQ-managed fisheries where ITQs consist of a harvest right is the implicit relationship between ITQ property rights and rights of access to the fishing grounds. This implicit spatial right to the grounds can provide obstacles in the way of allocating water-space within fishing grounds for alternative uses such as marine-protected areas, large-scale aquaculture, and wind farms. These lesser-known consequences of ITQ-managed fisheries are discussed here.  相似文献   

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