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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.
Japanese fisheries production in the Japan/East Sea between 1958 and 2003 increased to their peak (1.76 million tons) in the late 1980s and decreased abruptly with the collapse of Japanese sardine. Catch results for 58 fisheries and various environmental time-series data sets and community indices, including mean trophic level (MTL) and Simpson’s diversity index (DI), were used to investigate the impacts of fishing and climate changes on the structure of the fish community in the Tsushima warm current (TWC) region of the Japan/East Sea. The long-term trend in fisheries production was largely dependent on the Japanese sardine that, as a single species, contributed up to 60% of the total production in the Japanese waters of the Japan/East Sea during the late 1980s. Excluding Japanese sardine, production of the small pelagic species was higher during 1960s and 1990s but lower during 1970s and 1980s. This variation pattern generally corresponds with the trend in water temperature, warmer before early 1960s and after 1990s but colder during 1970s and 1980s. The warm-water, large predatory fishes and cold water demersal species show opposite responses to the water temperature in the TWC region, indicating the significant impact of oceanic conditions on fisheries production of the Japan/East Sea. Declines in demersal fishes and invertebrates during 1970s and 1980s suggested some impact of fishing. MTL and DI show a similar variation pattern: higher during 1960s and 1990s but lower during 1970s and 1980s. In particular, the sharp decline during the 1980s resulted from the abundant sardine catches, suggesting that dominant species have a large effect on the structure of the fish community in the Japan/East Sea. Principal component analysis for 58 time-series data sets of fisheries catches suggested that the fish community varied on inter-annual to inter-decadal scales; the abrupt changes that occurred in the mid-1970s and late 1980s seemed to correspond closely with the climatic regime shifts in the North Pacific. These results strongly suggest that the structure of the fish community in the Japan/East Sea was largely affected by climatic and oceanic regime shifts rather than by fishing. There is no evidence showing “fishing down food webs” in the Japan/East Sea. However, in addition to the impacts of abrupt shifts that occurred in the late 1980s, the large predatory and demersal fishes seem to be facing stronger fishing pressure with the collapse of the Japanese sardine.  相似文献   

3.
The tuna industry in the Western and Central Pacific Ocean (WCPO) is one of the most valuable fisheries in the world. Taiwan has a long fishing history and is one of the major distant water fishing nations in the surrounding area. This study aimed to review the historical cooperation structure between Taiwanese purse seiners and Pacific Island Countries (PICs). Data were collected by literature analysis and semi-standardized in-depth interviews with experts. The results showed that since 1982, the Taiwanese purse seiners have developed and signed bilateral access agreements with seven PICs under a variety of formats. The fisheries access and licensing arrangements have been transformed to a Vessel Day Scheme (VDS); as a result, the access fees have increased rapidly since 2010. Taiwanese industries have invested in facilities and share ownership with some PICs. Moreover, the Taiwanese purse seiner industries have proclaimed their willingness to follow the Western and Central Pacific Fisheries Commission conservation measures and stated that they will cooperate with PICs. They hold conservative views, however, regarding the further transfer of ownership to PICs. For the conservation of tuna resources in the WCPO, distant water fishing nations and PICs should cooperate to limit fishing capacity and ensure that the access fee benefits PICs.  相似文献   

4.
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   

5.
This article examines China's distant water fishing industry, with a focus on China's bilateral fisheries access agreements in Africa. The article argues that China largely conforms to international norms and rules on sustainable fisheries, but that challenges remain in efforts to work with China on the sustainable management of fish stocks. Developed countries contribute to China's policies and behavior in international fisheries in both positive and negative ways.  相似文献   

6.
This paper presents a historical account of Brazilian public policy on fisheries subsidies, and a discussion of problems and limitations resulting from such policy. From the 1960s to the mid-1980s, public policies led to a great increase in fisheries catch without appropriate consideration for the long-term sustainability of the resources, resulting in declining catches over the years. The goals of current Brazilian public policy on fisheries will not help in reducing overexploitation. This is because these policies are too optimistic about the abundance of fish in Brazil's EEZ, and are not accompanied by a fisheries management plan that is likely to work.  相似文献   

7.
This study integrates fisheries logbook data with observer and vessel monitoring system (VMS) data in order to assess the accuracy of reported data and to develop high-resolution spatial data suitable for use in local-scale marine spatial planning analyses. Spatial assessments were conducted on five nearshore commercial fisheries to provide baseline information to inform spatial management and conservation planning in Algoa Bay, South Africa. Clear spatial patterns in the distribution of fishing effort were apparent for the linefishery, chokka-squid and inshore demersal trawl sectors. Observer and VMS data confirmed the broad spatial distribution of resource-use patterns of logbook data. Combining these data sources allowed higher-resolution spatial indices of fishing effort to be developed, which are suitable for systematic spatial planning on a local scale and can be used for future spatial management and conservation.  相似文献   

8.
《Ocean & Coastal Management》2006,49(9-10):739-763
The framework for management of the ocean and coasts of the Pacific Islands region has been evolving since the early 1970s when Pacific Island countries played a significant role in the negotiations leading to the 1982 United Nations Convention on the Law of the Sea. Commencing with a summary of the provisions of relevant international instruments, this paper presents a broad overview of regional arrangements for ocean and coastal management in the Pacific Islands region. It considers the work of the various regional intergovernmental organizations with active programmes in ocean research and governance and the consultative arrangements that support coordination and collaboration. Consultative arrangements involving other stakeholders, such as local, regional and international nongovernmental organizations are summarised. To improve environmental governance and address increasing environmental threats, particularly in relation to coastal area management, consultative arrangements need strengthening. This applies equally to national and regional level consultation. The institutional and policy framework for the management and conservation of oceanic fish stocks that Pacific Island countries have been refining over a period of 25 years is suggested as providing useful lessons for strengthening coastal management processes and strategies in the region.  相似文献   

9.
Scientific information on the shrimp and groundfish resources of the Brazil–Guianas continental shelf has been produced by the United Nations Food and Agriculture Organization (FAO) and the Caribbean Regional Fisheries Mechanism (CRFM), in collaboration with the national governments exploiting the resources, since the early 1970s. In spite of the availability of such information, largely as grey literature, there is limited evidence as to the extent it is being used in fisheries management in Trinidad and Tobago. The flow of information between multiple stakeholders − fishing industry, scientists, fisheries managers, policy makers, and fisheries advisory bodies − was studied based on responses to a survey of key individuals to document each of their roles in the creation, distribution, and use of fisheries information. Content analysis of responses was completed to determine the opportunities and barriers for using scientific information in fisheries management. Salience, credibility, and legitimacy of the information were shadowed by barriers that decreased these attributes. Knowledge about the fishery has increased and technical capabilities have been strengthened through research. At the same time, advances in digital technology have made information more accessible. Yet, the high technical content of fisheries information reduced its usefulness to some stakeholders and formal systems do not exist for distributing or measuring the use and influence of such information in decision making. Communication strategies to promote awareness of the scientific information and aligning scientific information with fisheries policy could increase its use and influence. Institutional support for partnerships and education to encourage stakeholder involvement could also facilitate increased influence of scientific information.  相似文献   

10.
《Oceanologica Acta》1999,22(6):593-602
Major commercial fisheries for orange roughy (Hoplostethus atlanticus) occur on seamount features, which are widely distributed throughout the New Zealand region. When the fishery developed in the late 1970s to early 1980s, it occurred mainly on flat bottom, but over time has become more focused on seamounts. In the 1995–1996 fishing year, it is estimated that about 70 % of the catch of orange roughy within the New Zealand EEZ was taken from seamounts. Seamounts on the Chatham Rise have been fished for over ten years. Examination of commercial catch and effort data show strong declines in catch rates over time, and a pattern of serial depletion of seamount populations, with the fishery moving progressively eastwards to unfished seamounts along the southern margins of the Rise. Catch rates on seamounts in other regions of New Zealand have also generally shown a similar pattern of rapid decline. There is growing concern over the impact of trawling on seamounts, and the effects this can have on the benthic habitat and fauna, and the long-term sustainability of associated commercial fisheries.  相似文献   

11.
An examination of large archives (1950–1997) of the oceanographic and atmospheric data from the northwestern North Pacific Subtropical Gyre has revealed clear linkages between atmospheric forcing factors, physical processes and biological events. Large changes in the winter and spring biomass of phytoplankton and macroplankton observed over annual, decadal and inter-decadal time scales could clearly be attributed to climate-related changes in oceanographic processes. Interannual changes in the intensity of the winter-time East Asian Monsoon had a significant impact on the extent of convective overturning, on nitrate inputs into the euphotic zone and the concentrations of chlorophyll a in winter and during the following spring. A prolonged period of deeper winter mixed layers observed from the mid-1970s to the mid-1980s led to a sizeable increase in winter mixed-layer nitrate concentrations. This change resulted in a decrease in winter-time phytoplankton biomass. Spring-time chlorophyll a, in contrast, showed a steady increase during this period. The decline in winter phytoplankton biomass could be attributed to the depths of mixed layer. A deeper mixed layer prevents phytoplankton from remaining in the euphotic zone for long enough to photosynthesize and grow, leaving substantial amounts of nutrients unutilised. However, as a result of stratification of the water column in spring following each of these winters, phytoplankton could take advantage of the enhanced ambient concentrations of nutrients and increase its biomass. Another noteworthy observation for the period from the mid-1970s to the early 1980s is that the western subtropical gyre progressively became phosphate limited. The period of diminishing mixed-layer phosphate concentrations was observed in our study area from the early 1990s onwards was consistent with recent observations at Station ALOHA in the eastern subtropical gyre.  相似文献   

12.
The European Union has established a framework to achieve or maintain good environmental status in the marine environment by 2020. The Marine Strategy Framework Directive requires the application of the ecosystem approach to the management of human activities, covering all sectors having an impact on the marine environment. However, fisheries in the Mediterranean are far from a systematic implementation of an ecosystem-based fisheries management (EBFM). Aiming to address this issue, this study explores the potential of the relationship between daily yield by vessel (landings and income by species) and vessel position (known via vessel monitoring system) as a tool for fleet management. This approach is possible due to the current dynamics of Mediterranean fleets, with vessels returning daily to the harbour where landings are registered as weight and income by vessel. Moreover, vessels of >15 m total length have been compulsory monitored by VMS since 2005. A bottom trawl fleet that operates in the northwestern Mediterranean was chosen to develop this approach. Different groups of trawlers were identified, which could be linked to the strategies displayed by the fishermen that were mainly driven by the target species dynamics. Accurate knowledge of the fishing targets driving the fleet dynamics and of the fishing strategies at the vessel level (i.e. fishing ground habitat where the fishing pressure is exerted and corresponding landings) are shown to be a feasible tool for fleet management.  相似文献   

13.
Most fisheries management studies have concentrated on understanding resource dynamics and have paid less attention to understanding the dynamics of those who use the resources. This situation limits the knowledge about the fisheries system as a whole and specifically about the viability of management schemes. It is vital to understand how the actors within the fishing sector (fishing firm owners/managers, fishers, fisheries managers, and traders) may respond to changes in fishing resources trends, market dynamics, and fisheries policies before they are implemented. These issues are explored in this paper by applying a longitudinal analysis of the Yucatan Mexico's fishing industry. The analysis is presented within the framework of the theory of change and coping strategies. The study primarily involved interviews during 2008 with the main owners of companies in the fishing industry and with fisheries managers and other stakeholders. Time-series catch data on the main fishing resources are also reviewed to evaluate changes across three historical periods and describe how the actors have perceived and responded to those changes. Given conditions of uncertainty in resource availability, changes in market demand and changes in institutional arrangements, the viability of traditional business and resource management practices are discussed. The analysis presents different kind of triggers that have modified the conditions of the fishing sector and had had impacts on the socio-economic–ecological system in which fisheries are embedded. The need for adaptive strategies in the whole chain of the fisheries business and resource management is stressed, given the current changes and conditions of fisheries. The discussion states a series of actions that could improve the relationships between business practices and fisheries management.  相似文献   

14.
Most fisheries in China do not have maximum sustainable yield(MSY) estimates due to limited and poor data.Therefore, finding a common method to estimate MSY or total allowable catch(TAC) for fishery management is necessary. MSYs of three important fisheries in the East China Sea were evaluated through a catch-based model.Estimates for intrinsic rate of increase(r) and five levels of process error were considered. Results showed hairtail Trichiurus japonicas(Temminck and Schlegel) and small yellow croaker Larimichthys polyactis(Bleeker) fisheries experienced overfishing from the mid-1990 s to the early 2000 s, and the suggested TACs were 55.8×10~4 t and9.06×10~4 t, respectively. Decades of overfishing in wintering and spawning grounds of large yellow croaker Larimichthys crocea(Richardson) caused the fishery's collapse in the 1980 s, and it has not recovered until today.The Catch–MSY model generated similar estimated MSYs with other methods and may be a useful choice for the assessment of regional stocks in China.  相似文献   

15.
Large intensity and diversity of human activities result in an increase in complexity in the utilization of space. This paper describes the fisheries and a method to map fishing efforts and catches of different fleets by combining vessel monitoring system (VMS) data and logbook data. The method makes it possible to explore the spatial and temporal variability of fishing and the potential impacts of proposed management measures on the fisheries. The method is proposed to be used in the development of management plans for marine protected areas such as Natura 2000 sites, designated to protect vulnerable habitats and species.  相似文献   

16.
An in-depth assessment was conducted on the functioning of a Taiwanese Sakuraebi (Sergia lucens) fishery management institution to understand the role of leadership in the context of long-term incentive creation. Interviews with relevant stakeholders and statistical analysis of fisheries data indicated that the daily vessel quota system and fishers’ collective efforts to influence the market resulted in increased sales value, while simultaneously allowing for the equitable distribution of benefits from the Sakuraebi fishery in Donggang, Taiwan. Local fishers expressed a high level of satisfaction with the corresponding activities initiated by the fisher's organization. Interview respondents felt that promotional marketing activities led by the organization to enhance domestic consumption were particularly effective, and statistical analysis suggests that these activities helped to reduce the dependency of Taiwanese Sakuraebi fishers on export markets. A notable characteristic of this fishery is that it combines a large-scale sales organization, which enables the exertion of market influence, with a small-sized subsidiary organization for fisheries management. An annually rotating leadership system for managing fishery operations also provides members with the opportunity to share a sense of participation and responsibility, while keeping long-term policy goals. This study reinforces previous findings that leadership, social cohesion, and the nature of the resource are key factors determining the effectiveness and success of fisheries management.  相似文献   

17.
Peruvian anchovy (Engraulis ringens) stock abundance is tightly driven by the high and unpredictable variability of the Humboldt Current Ecosystem. Management of the fishery therefore cannot rely on mid- or long-term management policy alone but needs to be adaptive at relatively short time scales. Regular acoustic surveys are performed on the stock at intervals of 2 to 4 times a year, but there is a need for more time continuous monitoring indicators to ensure that management can respond at suitable time scales. Existing literature suggests that spatially explicit data on the location of fishing activities could be used as a proxy for target stock distribution. Spatially explicit commercial fishing data could therefore guide adaptive management decisions at shorter time scales than is possible through scientific stock surveys. In this study we therefore aim to (1) estimate the position of fishing operations for the entire fleet of Peruvian anchovy purse–seiners using the Peruvian satellite vessel monitoring system (VMS), and (2) quantify the extent to which the distribution of purse–seine sets describes anchovy distribution. To estimate fishing set positions from vessel tracks derived from VMS data we developed a methodology based on artificial neural networks (ANN) trained on a sample of fishing trips with known fishing set positions (exact fishing positions are known for approximately 1.5% of the fleet from an at-sea observer program). The ANN correctly identified 83% of the real fishing sets and largely outperformed comparative linear models. This network is then used to forecast fishing operations for those trips where no observers were onboard. To quantify the extent to which fishing set distribution was correlated to stock distribution we compared three metrics describing features of the distributions (the mean distance to the coast, the total area of distribution, and a clustering index) for concomitant acoustic survey observations and fishing set positions identified from VMS. For two of these metrics (mean distance to the coast and clustering index), fishing and survey data were significantly correlated. We conclude that the location of purse–seine fishing sets yields significant and valuable information on the distribution of the Peruvian anchovy stock and ultimately on its vulnerability to the fishery. For example, a high concentration of sets in the near coastal zone could potentially be used as a warning signal of high levels of stock vulnerability and trigger appropriate management measures aimed at reducing fishing effort.  相似文献   

18.
An overview of the Oyashio ecosystem   总被引:3,自引:0,他引:3  
The Oyashio shelf region and the seasonally ice-covered areas north of Hokkaido are highly productive, supporting a wide range of species including marine mammals, seabirds and commercially important species in the western subarctic Pacific. The fishes include gadids, such as walleye pollock and Pacific cod, and subarctic migratory pelagic fishes such as chum salmon and pink salmon. It is also an important summer feeding ground for subtropical migrants such as the Japanese sardine, Japanese anchovy, Pacific saury, mackerels, Japanese common squid, whales and seabirds. In recent decades, some components of the Oyashio ecosystem (i.e., phytoplankton, mesozooplankton, gadid fish, and subtropical migrants) have shown changes in species abundance or distribution that are correlated with environmental changes such as the 1976/1977 and 1988/1989 regime shifts. The First Oyashio Intrusion moved northward from the mid-1960s until the late 1970s, when it moved southward until the 1980s, after which it returned to the north again after the mid-1990s. The sea-surface temperature in spring decreased after the late 1970s, increased after the late 1980s, and remained high during the 1990s. The extent of ice cover in the Sea of Okhostk also decreased during the latest warming in the 1980–1990s but has increased again since the late 1990s. This and other variabilities affect the Oyashio ecosystem and the surrounding region.  相似文献   

19.
Southern rock lobster (Jasus edwardsii) support significant commercial and recreational fisheries in Tasmania, Australia. Since the mid 1990s the number of persons holding recreational lobster licences increased by over 80%, with c. 15 500 persons licensed in 2002/03. Assessment of the recreational fishery has been undertaken periodically since 1996 using a telephone‐diary survey method. The fishery was concentrated off the south‐east and east coasts of Tasmania and characterised by strong seasonality in catch and effort, which peaked markedly early in the fishing year (November‐January). Although pots were the most popular fishing method, daily catch rates by divers were more than double those for pots. Divers selectively harvested larger lobsters than those taken by pots and more frequently attained the daily bag limit of 5 lobsters. The estimated recreational harvest increased significantly since 1996/97 and in 2002/03 effectively reached a management trigger level of 10% of the total allowable commercial catch, flagging a review of recreational management arrangements.  相似文献   

20.
For the first time, the production of fisheries in Kuwait was assessed both quantitatively and qualitatively by comparing the production of the late 1980s and the mid-2000s using official data. The results indicate that total fisheries production has declined over time, with local production (artisanal and industrial) having decreased by approximately 25%, while imports increased by 25%, representing 62% of the total fisheries production over time. Current consumer preferences have led to increased demand of fish species formerly having inferior commercial importance. The verified per capita fish consumption in 2010 was 22.32 kg yr−1 suggesting the existence of an unrecorded supplementary supply of fish. Predictions show a dramatic decrease in fishery production by 2025, with a low supply of only 0.5 kg per individual per annum. The results have practical implications for legislators’ management strategies for the sustainability of local fishery stocks.  相似文献   

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