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1.
Artisanal fisheries throughout the Mediterranean region are managed mostly by applying gear specific regulations. The data about the extent and dynamics by which littoral fish resources respond to commonly proposed changes of such regulations are lacking. Here the results of a 15 year (1995–2009) monitoring programme of littoral fish resources in a pilot region of island Vis aquatorium, central Adriatic Sea, are reported with the scope of investigating whether a more restrictive fishing regime (encompassing an increase in minimum inner layer mesh size of trammel net from 28 to 40 mm and excluding the trammel net from subsistence artisanal fishing) that has progressively been put in place during the study period has been accompanied by expected positive changes of littoral fish resources’ abundance, biomass and structure. Significant increases over time were observed in most of the community indices analyzed (abundance and biomass catch per unit effort, diversity indices) as well as a directional change in abundance and biomass catch composition of littoral fish resources. Positive responses were, however, primarily related with a recovery of Mullus surmuletus stock. Additionally, time-series analysis of ABC curves and their corresponding W index revealed that fish community in the study area was still moderately disturbed. Limited extent of conventional management restorative potential is further exacerbated by social issues – noncompliant behavior mainly among subsistence artisanal fishers and consequent resentment of commercial artisanal fishers. In order to improve further the state of the resources a more comprehensive set of management measures incorporating closed areas and a new approach actively involving fishers in the management process should be adopted.  相似文献   

2.
Socio-economic development of small-island fishing communities is greatly dependent on local coastal and marine resources. However, illegal fishing and aggressive practices in insular ecosystems lead to over-exploitation and environmental deterioration. Moreover, a lack of scientific data increases uncertainty and prevents the adequate monitoring of marine resources. This paper focuses on the integration of local fishing communities into decision-making processes with the aim of promoting artisanal fishing on the Island of Tenerife (the Canary Islands), as a way to preserve the marine ecosystem and socio-economic development of traditional cofradias (fishers' organisations). A qualitative methodological framework, based on participatory problem-solution trees and focus groups, was used to identify the main factors impeding the sustainable development of the artisanal fishing sector on the island and to elaborate collective proposals with policy implications. The fishing community involved identified four main issues that are maintaining an unsustainable island fishery: 1) Over-exploitation; 2) Poor self-management of cofradias and commercialisation problems; 3) Fisher individualism and low co-management strategies, and 4) Illegal fishing increase vs. artisanal fishing decline. Results show the required policy enhancements to tackle them and the need to adapt regulations to the local situation.  相似文献   

3.
Cynoscion guatucupa Cuvier 1829 is a migratory pelagic fish species, which has a wide geographical distribution. It is the most important fishing resource for local communities in Bahía Blanca estuary and has been captured by artisanal fishermen since the 1900s. The industrial fleet has been fishing this species in the coastal area of Buenos Aires province since the 1950s, and, since 1970, landings have increased sharply. Between 2000 and 2004, the artisanal fishery in the estuarine waters of Bahía Blanca collapsed. Variations in total landings of the artisanal fleet might have arisen from the environmental variables within the estuary, fishing activity in the surrounding sea region, local pressure within the estuary and/or several other variables. Our results suggest that neither oceanographic parameters nor local pressure seem to have influenced the artisanal fishery of C. guatucupa in the estuarine region. Instead, this fishery seems to have been partially influenced by the increasing fishing pressure exerted by the industrial fishing fleet operating in open waters around the estuary. This study emphasizes the need to take into account fisheries data from both the estuarine environment and the surrounding sea region, particularly when designing management plans for the sustainable use of migrating fish resources.  相似文献   

4.
Decline in tuna fish stocks due to weak enforcement of regulations on fishing effort poses a challenge to the sustainability of tuna fishery. Intervention programs to address this problem require an understanding of the operational behaviour of the fishers and how various socioeconomic factors may impact fishers’ decisions to continue or discontinue their fishing efforts. A semi-structured interview questionnaire was developed to find whether fishers are willing to keep, change their fishing strategies or exit the fishery if their regular catch will decline by half. Boat captains, assistant boat captains and crew from General Santos City, Lupon, Mati City and Governor Generoso in the Philippines (n=293) were purposively selected for interviews. Results show that fishers from General Santos City with ancillary industries and Lupon with fewer economic development are more willing to adapt or change their fishing strategies. The catch value or price was found to have a strong influence on the likelihood that anchored FAD tuna fishers will adapt or change their fishing strategy when their catches decline. Fishers whose catch fetched a price of PhP 151.00 (US$ 3.48) and above Php 200 (US$ 4.61) have 80% probability to change their fishing strategy. The proportion of catch sold also had a high influence on the decisions to adapt in the fishery with fishers selling 36% and 73% of their catches have 100% and 70% probability to adapt. The results suggest a reluctance to exit the fisheries even when tuna fishing is no longer economically viable, fishers opt to adapt.  相似文献   

5.
This paper analyses how artisanal fleets in the South Atlantic Coast of Spain (Andalusia) are transformed at the macro-level by political and economic processes. The article will first describe the web of economic and political dynamics, and it will then outline several socioeconomic and cultural patterns of artisanal fleets, examining strategies that are used to encourage commercial specialisation, technological innovation, capitalisation and productive intensification. The resulting social conflict is also examined. From such a study, this essay intends to promote a theoretical debate concerning the importance of new conceptions of artisanal fishing today, a time when local and global processes are highly interconnected.  相似文献   

6.
High sea industrial longline fishing can be understood as a case study of the cultural, economic, environmental and social impacts of unsustainable fishing technology. While much attention has been attributed to the impact of industrial longlines on the marine ecosystem, little is known about the impact of longline fishing on local food security, employment, cultural belief systems and traditions, revenue generation from marine tourism and climate change. New data demonstrate that the contributions of Marine Protected Areas, marine tourism and recreational fishing to local coastal economies dwarf the contributions of longline fishing. When combined with the impact of overfishing on coastal fishing communities and fish consumers, policies promoting sustainable fisheries must be expanded to take these other factors into account along with issues of biodiversity.  相似文献   

7.
Robert Ovetz   《Marine Policy》2006,30(6):809-820
Industrial longline fishing can be understood as a case study of the cultural, economic, environmental and social impacts of unsustainable fishing technology. While much attention has been attributed to the impact of industrial longlines on the marine ecosystem, little is known about the impact of longline fishing on local food security, employment, cultural belief systems and traditions, revenue generation from marine tourism and climate change. New data demonstrate that the contributions of Marine Protected Areas, marine tourism and recreational fishing to local coastal economies dwarf the contributions of longline fishing. When combined with the impact of overfishing on coastal fishing communities and fish consumers, policies promoting sustainable fisheries must be expanded to take these other factors into account along with issues of biodiversity.  相似文献   

8.
史磊  秦宏  刘龙腾 《海洋科学》2018,42(11):126-134
由于海洋渔业资源的衰退,目前世界海洋捕捞业进入"零增长"的徘徊期。当前世界海洋捕捞业呈现以下发展趋势:海洋渔业资源争夺日益激烈,海洋捕捞业管理制度日益严格,世界海洋捕捞业产业转移趋势日趋明显,海洋捕捞业技术装备要求越来越高,国际社会越来越重视海洋捕捞业可持续发展。面对世界海洋捕捞业的发展趋势,我国应当继续发展资源养护型海洋渔业,从生态系统角度考虑海洋捕捞业管理措施,积极稳妥发展远洋渔业,参与国际渔业资源的开发,重视海洋捕捞业装备技术水平的提高。  相似文献   

9.
This brief note is an update to the authors' "The Expansion, Limit and Decline of the Global Marine Fish Catch," published in the September 2012 issue of Marine Policy. That paper examined the steady increase in the world's catch from 1950 to 1989, its slight decline and rise to a final peak in 1996. This limit has been followed by a steady decline to 2010. Since there have been improvements in the technology of fishing and no reason to believe that there has been a reduction in fishing effort, then the apparent limit and subsequent decline in the catch suggests a reduction in the supply of fish and invertebrates in the world's oceans. The earlier paper also noted the geographic shift in the world's catch to Asia and the rise of China to become the world's largest catcher of fish.  相似文献   

10.
The bluefin tuna fishery has undergone a major shift in Malta, moving from an open access artisanal nature to a privatized and industrialized activity dominated by the purse seining fleet and the BFT ranching industry. The shift has been exacerbated by the national implementation of an individual transferable quota system, which has enabled the concertation of quotas into fewer hands. The main objective of this article is to understand how privatization has evolved within the sector and the way the Maltese artisanal fishermen are experiencing the shift. This study takes an exploratory mixed-method approach to quantitatively and qualitatively understand how policy underpinnings interplay with the sustainability dimension of the small-scale fishing sector. Results show that the transition of the bluefin tuna fishery from artisanal to industrial has generated a legitimacy crisis over fishing rights, decreased profitability amongst most of the artisanal fleet, and led to a series of socio-ecological impacts on the artisanal fisheries system at large. It is concluded that the neo-liberal trajectories of industrialization have directly undermined the continued sustainability of artisanal fishing communities.  相似文献   

11.
In the last years, the overall fish industry in the lagoon of Venice has shown a gradual decline. In order to better understand this process, we carry out a socio-economic questionnaire next to the fisherman population. Questionnaire contains significant qualitative and quantitative data that allow us to evaluate the social and the cultural profile of the respondents, including information with respect to the different technological fishing characteristics involved, type and amount of the species harvested as well as the overall productivity of the activity. Furthermore, the questionnaire contains an economic valuation exercise so as to assess in monetary terms the preferences of the fishermen with respect to different alternative policy options that may characterize a future regulation of this economic activity. Estimation results show that fishermen welcome any regulation initiative that is characterized by: (1) banning all fishing activities during the night, (2) allocating fishing concessions areas to each fishermen in a way that minimize the distance between the fishing area and the harbor, and (3) by introducing of a labeling mechanism that certifies the origin of the product. Moreover, the underlying economic valuation mechanism reveals to sensitive to respondent's motivational profile, including the overall trust and confidence that fisherman community places on the current institutional bodies. This result reveals to be of particular significance when attempting the design of an efficient, widely supported regulation of the fishing activity in the lagoon of Venice.  相似文献   

12.
‘Human-dolphin (Tursiops truncatus Montagu, 1821) cooperative fishery’ and its influence on cast net fishing activities in Barra de Imbé/Tramandaí, Southern Brazil - aims to describe ‘fishing with dolphins’ or ‘botos’ (Tursiops truncatus Montagu, 1821), its importance in mullet fishing in conjunction with the traditional knowledge of artisanal fishermen, and the negative economic impact that tourism has had on mullet fishing in Barra de Imbé/Tramandaí (29°58′S 50°07′W). In November and December of 2009, 22 artisanal fishermen associated with the Tramandaí Fishermen’s Union were interviewed. During these interviews, questionnaires were employed utilizing both open and closed questions that dealt with behavioral ecology, biological and interactional issues related to bottlenose dolphins, and small-scale fishing in the region. All those interviewed described “boto fishing,” in which bottlenose dolphins “helped out the fishermen.” According to these interviews, this kind of fishing, marked by close interaction between humans and ‘botos,’ allows nets to be cast fewer times and with captured fish yields that are greater than, when there is no dolphin is present. The fishermen maintain that this increased productivity results from ‘botos’ showing them exactly where the schools of fish are located below the water surface. This has made it possible to observe the impact that dolphin fishing has on the monthly incomes of these fishermen, and there is concern among fishermen, that the intense tourism may one day contribute to the disappearance of the ‘boto,’ a situation, they believe would negatively affect their fishing activities.  相似文献   

13.
A rejoinder to our recent paper suggests that there has been confusion over our central point. The 85 IUCN Red List Threatened species that the International Game Fish Association issues world records became threatened due to commercial overfishing, not recreational. However, given that they are threatened now, we have concerns about trophy fishing for them, at least in the current form that precludes catch and release. Additionally, while the IGFA claims that an insignificantly low number of record applications for these species have been submitted, many more anglers attempt to catch a large fish than end up submitting record applications. We are grateful for the opportunity to discuss this important issue.  相似文献   

14.
A large number of the marine protected areas (MPAs) designated in Spain have been proposed by public authorities or conservation NGOs in conjunction with their own administrations and other social and economic stakeholders. The only examples to date of MPAs proposed by fishing interests – the fishermen and their organizations – are located at Cedeira and Lira, two small communities in North West Spain. These fishing interests have been involved in these two proposals from the start, including design and development, as well as internal awareness-raising. However, 5 years from the outset, both marine reserves have failed to meet the conditions and essential requirements of a successful fisheries management system. This paper evaluates how the artisanal fishing sector has been identified with the idea of sustainability; and how the role and power relations of the Galician regional administration acquired both the key institutions of co-management and their associated functions which have conditioned the consolidation process of these marine reserves.  相似文献   

15.
Over the last several years, significant regulatory changes related to Pacific halibut Hippoglossus stenolepis have occurred in the for-hire recreational charter boat fishing sector in Alaska. In addition to limited entry restrictions and adoption of a catch sharing plan that provides a formal means of determining allocation between the commercial and charter boat fishing sectors, more restrictive harvest regulations were placed on anglers fishing from charter boats. This article provides insights into how the value anglers place on charter boat fishing is affected by these regulations, principally bag and size limits. Such information is helpful in assessing the trade-offs in economic benefits associated with different regulatory tools used to manage angler harvest levels. Stated preference choice experiment data from a 2012 survey are analyzed using a panel rank-ordered mixed logit model to estimate the economic value, or willingness to pay (WTP), non-resident anglers place on saltwater charter boat fishing trips in Alaska and to assess how changes in characteristics of fishing trips, particularly harvest restrictions related to Pacific halibut, affect this value. The model specification accounts for a wide array of size and bag limit restrictions that have been recently implemented or are under consideration by Pacific halibut fishery managers. The results indicate that very strict harvest restrictions have the effect of driving WTP to zero, while allowing at least one (potentially) large fish to be caught is valuable to anglers. The results also suggest that WTP for fishing trips with bag limits that allow two or more fish to be harvested with no size restrictions on the first fish harvested are not statistically different from the value for trips for larger bag limits or for the case where all the fish in the limit can be any size. This suggests that fishery managers can restrict the size of the second fish in a two-fish bag limit and still maintain economic values for fishing trips.  相似文献   

16.
Information coming from fishery monitoring, surveys and experimental fishing with participation of fishers was employed to determine the impact of an artisanal gear, ‘boliche’, on the biodiversity of the Ciénaga Grande de Santa Marta (CGSM), an estuarine lagoon on the Caribbean coast of Colombia. Fishery monitoring (catch data) included landings before (1968 and 1978) and after (1994–1996) the introduction of the boliche in the CGSM (1985), whereas surveys were conducted seasonally during 1993–1994. Fishing experiments involved evaluating different mesh sizes and the short-term effect of physical disturbance by the boliche. Monitoring suggested potential trophic effects of this fishing gear: the catch of large, long-lived, carnivorous species declined after the introduction of the boliche in the CGSM, whereas catch rates of smaller, shorter-lived, and lower trophic level species increased. Surveys revealed that the boliche retained 41 species. The by-catch made up 62% of the total catch and the remaining 38% involved the three target species Eugerres plumieri, Mugil incilis and Cathorops spixii. Selectivity experiments showed that 2.5 in. stretched mesh size gill nets caught more species than the 3.0-in. mesh. The smaller mesh also increased the risk of a critical reduction in the spawning stock of target species (notably E. plumieri); a situation that could affect the fish community if mesh sizes lower than 2.5 in. were intensively used. Suspended particulate matter significantly increased after fishing activity, with higher resuspension on mud-shells and mud substrata, whereas dissolved oxygen showed no appreciable changes after fishing operations. Notwithstanding, the activity of the boliche would generate sediment resuspension between 382 and 470 t day−1, which could lead to potential cascade impacts on water quality. We propose a framework of redundancy in management measures in order to simultaneously reach management and conservation goals.  相似文献   

17.
El Salvador is one of the most environmentally degraded nations in Latin America, but the declining fishing industry is under-studied compared with deforestation and landuse. This paper examines the reactions to fish stock decline of two generations of fishers in La Union, El Salvador on the Golfo de Fonseca, one of the most important fishing areas in Latin America, using face to face interviews and questionaires. Both older (>35 years) and younger (<36 years) fishers supplemented their income with trading, farming and loans from their relatives in the United States. All older fishers reported larger fish catches five and ten years previously than at present. Previously, fishers caught more fish, but significantly more younger fishers than older fishers reported their fathers caught more fish than they did, indicating an increasing gap in fish catches in recent decades. More younger fishers than older fishers had fathers or male kin who were also fishers, indicating young men were less likely to join fishing without a parent or kin already involved. Minorities of both older and younger fishers engaged in supplementary activities. Environmental degradation disuaded fishers from switching to farming or hunting. The findings are similar to findings elsewhere on the decline of fish resources and generational gaps in environmental knowledge, but differ in that some other studies report fewer opportunities for fishers to access alternative or complementary activities. These findings are relevant to Latin American studies, considering the great value of the Golfo de Fonseca to the livelihoods of Central America.  相似文献   

18.
The present study assessed trends in resource-use, partitioning and management in the Ungwana Bay fishery, Kenya, using surplus production models. The fishery is one of East Africa’s important marine fisheries sustaining a bottom trawl commercial fishery and a resident-migrant artisanal fishery. Two models: Schaefer (1954) and Gulland and Fox (1975) were applied to catch-effort data over a 21-year period to model maximum sustainable yield (MSY) and optimal effort (fMSY) to examine the status of resource exploitation and provide reference points for sustainable management. In the artisanal fishery, model MSYs range from 392-446 t to 1283-1473 t for shrimps and fish respectively compared to mean annual landings of 60 t for shrimp and 758 t for fish. These landings represent <50% of the model MSYs suggesting under exploitation in the sub-sector. Moreover, current fishing effort applied stands at <0.5 fMSY. On the other hand, mean annual landings in bottom trawl commercial fishery, at about 330 t for shrimps and 583 t and fish represent about 90% of the model MSYs of 352-391 t and 499-602 t for shrimps and fish respectively. Therefore, the bottom trawl commercial fishery is likely under full exploitation. Similarly, the current effort is estimated at >0.7 fMSY. Resource management in the bay is faced with numerous problems including resource-use conflicts, poor economic conditions in artisanal fishery, poor legislation, and inadequate research augmented by poor reporting systems for catch-effort statistics. Thus, the fishery lacks clearly defined exploitation regimes. Fisheries research and assessment of the marine resources are important for sustainability of the fishery. Moreover, income diversification in the poverty ridden artisanal fishery would go a long way in addressing resource-use conflicts and use of deleterious fishing methods in the sub-sector. Borrowing from the successes of the Japanese community-based fisheries resource management (CBFRM) which has easily resolved numerous fisheries management issues in coastal small-scale commercial fisheries, and the beach management unit (BMU) system which has been applied to the artisanal fisheries of south coast Kenya with enormous benefits, it is envisaged that a hybrid CBFRM-BMU system presents the best approach to sustainable resource-use in the Ungwana Bay fishery.  相似文献   

19.
副渔获物对渔业资源的影响及其减少方法的探讨   总被引:1,自引:0,他引:1  
由于渔具不同的选择性和多鱼种鱼类共栖 ,人们在对目标种类进行捕捞时 ,不可避免地产生副渔获物及其抛弃。由于渔业资源的下降和人们对海洋环境保护意识的加强 ,副渔获物及其抛弃问题日益成为人们关注的焦点。本文对世界范围内的渔业活动所产生的副渔获物进行分析 ,根据副渔获物的种类、被抛弃情况和原因以及对渔业资源的影响 ,提出了减少副渔获物和抛弃的方法。  相似文献   

20.
In a context of growing fishing pressures and recommendations for an ecosystem approach to fisheries, there is a need to monitor changes in fish communities over time. In this study, we analysed data from scientific trawl surveys carried out on the continental shelf off Guinea between 1985 and 2012. We performed factorial analyses and calculated biodiversity indices to characterise the changes in the structure and composition of fish communities that occurred over the 28-year period in this area, particularly given intensive fishing activities. We show that, over the study period, fish communities on the Guinean shelf were structured primarily according to spatial factors, with temporal changes being less pronounced than expected. However, a temporal analysis of biodiversity indices and species dominance showed that the intensification of fishing had significant effects on the general ecological features of the fish assemblages under study. There was a decrease in fish density and in mean trophic level. In addition, there were changes in species dominance, whereby large, slow-growing species with high commercial value were gradually replaced by smaller, fast-growing species of lesser commercial interest. These results from field observations are in line with some conclusions from previous modelling studies in the same geographical area, and provide further support for the hypothesis of a progressive ‘ecosystem effect of fishing’ occurring in Guinean waters.  相似文献   

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