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1.
《Marine Policy》2017
In countries like Sierra Leone, where stock assessments based on fisheries-independent data and complex population models are financially and technically challenging, catch statistics may be used to infer fluctuations in fish stocks where more precise data are not available. However, FAO FishStat, the most widely-used time-series data on global fisheries ‘catches’ (actually ‘landings’), does not account for Illegal, Unreported, and Unregulated (IUU) catches and relies on statistics provided by the national agencies of each member country. As such, reported FishStat data is vulnerable to changes in monitoring capacity, governmental transitions, and budgetary constraints, and may substantially underestimate the measure of extracted marine resources. In this report, Sierra Leone's total catches by all marine fishing sectors were estimated for the period 1950–2015, using a catch reconstruction approach incorporating national data, expert knowledge, and both peer-reviewed and grey literature. Results demonstrate that a substantial amount of marine resource exploitation is not represented in official statistics, and reconstructed catches represent more than 2.25 times the recorded FAO Fishstat values. Notably, foreign fleets take the vast majority of industrial catch in Sierra Leone's EEZ, indicating that most of the resource catch and revenue is diverted to foreign companies and export markets. While foreign actors dominate the industrial sector, the small-scale sector represents the majority of domestic catch. Illegal fishing is also a substantial challenge in Sierra Leone, and extracts a large amount of the country's marine fish resources. Reconstructing catches in Sierra Leone also highlights the impacts of various historical events such as Sierra Leone's civil war and post-war reconstruction on the development of the fisheries sector. The results found in the reconstruction present a large discrepancy from FishStat data, with considerable implications for assessment of stocks and management of Sierra Leone's marine resources. 相似文献
2.
Colombia has coasts on both the Atlantic and Pacific Oceans, but its marine fisheries are limited by the relatively small size of commercially important stocks. However, diverse fishery resources have traditionally been exploited by coastal communities, and industrial fisheries have grown in recent years with the intensification of tuna fishing in both oceans. The management of Colombia's fisheries has been hampered by frequent administrative changes, which has notably led to the disappearance of a part of the official landings data. We estimated total fisheries removals (reported plus discards and unreported catches) in the Colombian Atlantic and Pacific Oceans for the period 1950–2006. We used secondary sources of information to estimate missing data, and we estimated subsistence fishing and the unreported by-catches of the shrimp and tuna fisheries. We used available information on seafood prices to estimate the relative economic impact (gross revenues) of the small-scale and industrial sectors for the period 2000–2006. Our results suggest that for the period 1950–2006, the Colombian marine fisheries catches may have been almost twice the landings reported by FAO on behalf of the country (2.8 times higher in the Atlantic; 1.3 times higher in the Pacific). Although the total gross revenues of industrial fisheries were higher than those of the small-scale sector, the latter commanded higher gross revenues in the Atlantic in 2006. 相似文献
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4.
Many fish stocks in the world are depleted as a result of overexploitation, which reduces stock productivity and results in loss of potential yields. In this study we analyzed the catch trends and approximate thresholds of sustainable fishing for fished stocks to estimate the potential loss of catch and revenue of global fisheries as a result of overexploitation during the period of 1950–2010 in 14 FAO fishing areas. About 35% of stocks in the global marine ocean have or had suffered from overexploitation at present. The global catch losses amounted to 332.8 million tonnes over 1950–2010, resulting in a direct economic loss of US$298.9 billion(constant 2005 US$).Unsustainable fishing caused substantial potential losses worldwide, especially in the northern hemisphere.Estimated potential losses due to overfishing for different groups of resources showed that the low-value but abundant small-medium pelagics made the largest contribution to the global catch loss, with a weight of 265.0 million tonnes. The geographic expansion of overfishing not only showed serial depletion of world's fishery resources, but also reflected how recent trends towards sustainability can stabilize or reverse catch losses.Reduction of global fishing capacity and changes in fishery management systems are necessary if the long-term sustainability of marine fisheries in the world is to be achieved. 相似文献
5.
《Marine Policy》2017
Comments are provided on several points in the 2016 State of the World Fisheries and Aquaculture produced by the Food and Agriculture Organization of the United Nations (FAO). It is shown that data assembled by FAO from submissions by countries suggest a “stable” trend mainly because the declining catches of a number of countries with reliable statistics is compensated for by unreliable statistics from countries where reporting increasing catches may be politically expedient, e.g., China, Myanmar. Also, concerns are raised as to why FAO chose to ignore the well-documented data ‘reconstruction’ process, which fills the gaps that exist in data reported by countries to FAO. It is being ignored despite its importance for governance and resource conservation being well known. This process and its findings could be used by FAO to encourage countries to improve their data reporting, including retroactive corrections. This is important in view of successive analyses of the status of fisheries resources undertaken by FAO (published in current and past SOFIAs) and also in modified form by the Sea Around Us. This suggests a degradation of marine fisheries, and, if trends continue, a crisis by mid-century. Finally, comments are presented on the proposition that aquaculture will overtake wild capture fisheries in terms of food production, notably because current aquaculture requires huge quantities of wild-caught fish as feed. Indeed, this emphasis on aquaculture-as-substitute for fisheries raises issues of food security and malnutrition in developing countries, from which much of the fish used as feed originates. 相似文献
6.
《Marine Policy》2017
This article presents the first bottom-up analysis of the proportion of global marine fisheries subsidies to small-scale fisheries (SSF). Using existing data, the reported national subsidy amounts are split into the fraction that goes to small- and large-scale fishing sectors. Results reveal a major imbalance in subsidy distribution, with SSF receiving only about 16% of the total global fisheries subsidy amount of $35 billion in 2009. To bring this into perspective, a person engaged in large-scale fishing received around 4 times the amount of subsidies received by their SSF counterparts. Furthermore, almost 90% of capacity-enhancing subsidies, which are known to exacerbate overfishing go to large-scale fisheries, thus increasing the unfair competitive advantage that large-scale fisheries already have. The developmental, economic and social consequences of this inequity are huge and impair the economic viability of the already vulnerable small-scale fishing sector. Conclusions indicate that taxpayers' money should be used to support sustainable fishing practices and in turn ocean conservation, and not to foster the degradation of marine ecosystems, often a result of capacity-enhancing subsidies. Reducing capacity-enhancing subsidies will have minimal negative effects on SSF communities since they receive very little of these subsidies to begin with. Instead, it will help correct the existing inequality, enhance SSF economic viability, and promote global fisheries sustainability. 相似文献
7.
《Marine Policy》2016
The scarcity of data on fish catches difficult management of small-scale fisheries in developing countries. This study applies fishers’ knowledge to investigate temporal changes in the amount (biomass) and composition (major ecological categories) of fishing resources exploited by small-scale coastal fisheries in the southeastern Brazilian coast. Four hypotheses were investigated: (1) The amount of fish caught reported by fishers would decrease over time. (2) Older fishers would report higher fish catches than younger fishers. (3) Recent interviews would mention large-sized predators less often. (4) Recent interviews would mention less high valued fishing resources. Interviews with 421 fishers in 36 communities in the southeastern Brazilian coast were analyzed, covering a time span of 14 years, from 1995 to 2009. The hypothesis 1 was confirmed, 3 was partially confirmed, while 2 and 4 were not confirmed. Fishers’ age was unrelated to all variables. The results from fishers’ interviews indicated the temporal trends of: (1) a decrease in the biomass of fish caught; (2) an increase in the occurrence of smaller fish and invertebrates in the catch; (3) an increase of high value fishing resources; and (4) maintenance of large predators. The first two indicators suggest excessive fishing, but the later indicators (3 and 4) suggest that the socioecological system of the southeastern Brazilian coast had not yet undergone major ecological shifts. 相似文献
8.
《Marine Policy》2014
Managing small-scale fisheries in a developing country like the Philippines is very challenging because of high pressures from expanding fishing population, poverty and lack of alternative options. Thus, resource-focused fisheries management initiatives such as marine protected area (MPA) establishment will likely result in further marginalization of the poor fishers which could pose more serious problems in coastal communities. In this study, the status of small-scale fisheries in 44 coastal towns in the Philippines was assessed using FISHDA (Fishing Industries' Support in Handling Decisions Application), a simple decision support tool which requires minimal or easily-generated data. Results showed that 68% (30 out of 44) of the studied towns have unsustainable fisheries unless 58% of their fishing grounds are protected from all fishing activities. Alternatively, 53% of the active fishers in towns with unsustainable fisheries must totally stop fishing to avert fishery collapse. Alarming as it may sound, this is still an underestimate as catches incurred by the highly efficient and destructive illegal fishing activities such as blast, poison and large-scale fishing, which are reported to be still rampant in many coastal areas in the Philippines, were not accounted for in this study. This study demonstrated that MPAs alone may not be enough to avert fishery collapse even if MPA size is increased from the current 3% to 15% of the municipal waters, i.e. up to 15 km from the shore, as required by the Philippine law. Various challenges confronting the fishery and important recommendations to address them are further discussed. 相似文献
9.
渔获物平均营养级（Mean trophic level of fishery landings,MTL）是目前评估人类捕捞活动影响的研究中使用最广泛的生物多样性指标之一。根据联合国粮农组织FAO提供的渔获生产统计数据,结合Fishbase提供的相关鱼种营养级数据,本文评估了1950-2010年太平洋、大西洋和印度洋各沿海国海洋渔业开发状态。研究发现,在全球三大洋75个主要捕捞国中,43个国家MTL呈显著下降趋势,发生了Pauly于1998年提出的“捕捞降低海洋食物网”现象;但是,仅16个国家MTL的下降是由于高营养级种类的衰退,而27个国家属于“捕捞沿着海洋食物网”的下降机制。此外,20个国家MTL呈恢复上升趋势,但是,该恢复上升趋势通常伴随着传统低营养级种类产量的大幅下降;在上述20个国家中,11个国家的低营养级鱼类产量呈显著下降趋势。需谨慎分析“捕捞降低海洋食物网”现象,掌握MTL的潜在变化机制。 相似文献
10.
China(herein referred as China’s mainland,and excluding Hong Kong,Macao and Taiwan)ranks as the world’s leading fishing nation,with approximately 11.1 million tons of domestic marine catch acquired in 2017.Marine fisheries resources in China are mainly exploited by its 11 coastal provinces and municipalities,and the development of fishing industry varies among them.However,few studies have examined the exploitation history of the 11 coastal provinces and municipalities.In this paper,we systematically quantified the exploitation history of marine fishery resources in China and then measured the vulnerability of the 11 coastal provinces and municipalities of China to a reduction in marine catches.Our analysis suggested that Chinese marine fisheries experienced rapid growth from the mid-1980 s to the end of the 20 th century,and this rapid increase in marine catches were mainly promoted by increased fishing effort.The total primary production required level amounted to approximately 80%of the average primary productivity in 2017,and Zhejiang,Fujian,Shandong,Hainan and Guangdong provinces were the main fishing provinces in China.By assessing three dimensions of vulnerability(exposure,sensitivity and adaptive capacity)to the impacts of a reduction in marine catches in the 11 coastal provinces and municipalities,we found that Hainan,Guangxi,Zhejiang and Fujian provinces had high or very high vulnerability,while the municipalities of Shanghai and Tianjin had low vulnerability.Identifying suitable adaptation policies and management plans based on the differences in vulnerability among coastal provinces is important in sustainable fisheries management. 相似文献
11.
Madagascar, the world's fourth largest island, is one of the world's poorest developing countries, and its people depend heavily on marine resources for subsistence and income. Exports of these resources and foreign fishing access agreements are also important, at least from a large-scale economic perspective. In recent years, concerns have been voiced amongst local fishers and industry groups regarding the growth of the country's fishing effort. Despite these concerns, existing knowledge of the scale, composition and trends of Malagasy fisheries remains poor, and there is negligible information regarding unreported catches and illegal fishing in Madagascar's waters. Small-scale fisheries, which are often substantial in developing countries such as Madagascar, are often unreported or underestimated. Unfortunately, fisheries legislations, management plans and foreign fishing access agreements are often influenced by these incomplete data, leading to serious over-estimations of resource availability. This also appears to be the situation in Madagascar, where the reconstruction of total catches by all Malagasy fisheries sectors conducted here showed that total catches between 1950 and 2008 were twice the volume reported by national fisheries agencies. Most importantly, much of the subsistence sector is missing from official statistics, and signs of decline have already been observed in several stocks, suggesting that current levels of catches are likely to be exceeding sustainable yields. This has profound implications for the economic and ecological sustainability of fisheries, as well as food security in a country where people rely heavily on the ocean for their daily protein needs and livelihoods. 相似文献
12.
《Marine Policy》2017
Small-scale fisheries have been estimated to contribute up to 30% of the global landed value, which is caught by approximately 22 million fishers, some of which can be attributed to developed countries. Socio-economic analysis of small-scale fisheries often focuses on developing countries and fails to recognize the presence and contribution of small-scale fisheries in the developed world. Fisheries in British Columbia are diverse and often regarded as being industrialized and large-scale when analyzed in a global context. This study aims to demonstrate that features of small-scale fisheries are present within British Columbia's fleets. A list of re-occurring features of small-scale fisheries is curated from the literature to capture physical, economic and social features of small-scale fisheries. These commonly identified features of small-scale fisheries are applied to Aboriginal Food, Social and Ceremonial fisheries and all commercial fisheries in British Columbia are analyzed to determine the presence or absence of each small-scale fishery feature. The results of this research create a gradient of fisheries from smallest to largest scale. This approach determines that Aboriginal Food, Social and Ceremonial fisheries are the most small-scale, while the sablefish fishery is the largest scale. The qualitative nature of this framework creates an opportunity for any group of fisheries in the world to be compared. 相似文献
13.
《Marine Policy》2017
The effects of recreational fishing on marine stocks and ecosystems have raised global concern in recent years. In Argentina, Southwest Atlantic, angling, netting and spearfishing of coastal bony fishes, sharks, rays and chimaeras are very popular pastime activities with more than 50 years of history. Despite the perceived traditional and economic relevance of these activities in the country, marine recreational fisheries were largely unregulated, and no official fisheries monitoring programs at the national level have been ever put in place. Except for a few particular systems for which some catch-and-effort data were collected by research institutions and non-governmental organizations, no comprehensive surveys aimed at describing the ecological, social or economic aspects of these fisheries have been made. Here, an updated review of the regulations in place for marine recreational fisheries along the Argentine coastline is presented. Of the five coastal provinces encompassing ca. 8400 km and about 20 latitude degrees (~36°S to 55°S) of coastline, only Buenos Aires province has a thorough legislation for its whole territory, which includes 15 protected areas. In the remaining provinces, the regulations for marine recreational fisheries are limited to a few protected areas (seven out of 37 coastal areas under provincial, national or shared jurisdiction). This lack of legislation encourages alleged recreational fishers to develop small-scale commercial fishing operations that are neither controlled nor monitored as such, contributing to the overexploitation of some key coastal stocks. 相似文献
14.
《Marine Policy》2013
It is well recognized that not all fisheries catches are reported or recorded properly by either government or non-government agencies. These unreported catches can be illegal, of unregulated species, or simply not monitored due to logistical barriers. In Mexico, these barriers are an extensive and often not easily accessible coastline, mostly de facto open access fisheries, poor administrative practices and generalized corruption in the fishing sector as a whole. These conditions were likely promoted early in the last century through the government's largely successful policies to increase fisheries catches and stimulate employment and economic growth. Many years later and amid declines in fish stocks and subsequent economic benefits, most notably at local scales, it is evidently time for a fundamental change in strategy away from expansion of fishing effort and toward ecological and economic sustainability. An important step in this endeavor is to provide a quantitative pre-mortem analysis of Mexico's total marine fisheries catches during the last half-century. Results suggest that from 1950 to 2010, total catches were nearly twice as high as the official reports, with an average annual catch of 1.5 million tonnes (t) compared to 796 thousand t in official statistics. In the last year of available data, 2010, official and total estimated catches were 1.5 million and 2.2 million t, respectively. While these results may be perceived as a criticism of the status quo and ante, this study actually does not single out a responsible party, but is, rather, a call to the many sectors of society who contribute to a lack of control, to help overcome these conditions, and increase and sustain the benefits from Mexico's marine fisheries. 相似文献
15.
The Food and Agriculture Organization (FAO) Committee on Fisheries (COFI) adopted an International Plan of Action for the Management of Fishing Capacity, which calls for all member states to achieve efficient, equitable and transparent management of fishing capacity by 2005. Based on the theoretical review of fishing capacity management, this paper examines the major practices made by China's government in managing the fishing capacity of its marine capture fisheries. Finally, it categorizes the main practices and then analyses and evaluates their effects. 相似文献
16.
《Marine Policy》2015
Should rural commercial small-scale fishing opportunities be closed to minimise effort and safeguard marine resources or open to offer livelihood support? In the Bijagós Archipelago (Guinea-Bissau) investigating employment pathways indicates that the sector is encouraging a diversity of institutions to flourish, reaffirming our understanding of the critical ‘safety-net’ function small-scale fishing affords. Results support the need to examine developing country smaller-scale fisheries in terms of wider social opportunities and not purely in terms of their own limitations. 相似文献
17.
《Marine Policy》2013
Spatialized catch and effort data, representing the world's marine fisheries in the 1950s and the 2000s are presented in form of cartograms, i.e., global maps in which the surface areas of continents are made proportional to the magnitude of the annual catches and fishing effort by their fleets. This is complemented by an analysis of the flows of seafood between the continents in whose waters the fish were captured, in the 1950s and the 2000s, and the continents where fleets originated. Such broad-brush analyses of temporal changes and trade patterns are helpful to understand major trends of fisheries, which, are increasingly dominated by scarcity of fish, and competition, notably off the coast of West Africa, and in newly accessed polar waters. 相似文献
18.
《Marine Policy》2014
This study examined the perceptions of fishers from two fishing communities with differing use histories and involvement in the long-standing (16 yr) multiple use Mafia Island marine protected area (MIMP), Tanzania. A randomly distributed questionnaire indicated that 94% of fishers believed that without the MIMP, there would be overfishing, dynamite use, destroyed habitats, and few fish. Fishers were more positive about core zones (no-take fishery closures) than general use zones (areas allowing selective fishing) as a consequence of increases in fishing pressure. Those that reported increased catches and sizes of fish since the creation of the MIMP were more likely to agree with present zone locations and more positive in general about fisheries and conservation planning. Most thought that fish size and gear restrictions were preferable to permanent closures. Perceptions differed among communities and gear users. Community and gear type explained 46% of the variance in responses about the perception that fisheries and conservation are compatible goals. Somewhat surprisingly, these effects were more important than catch increases or involvement in MIMP-related activities. The differences in perception between communities may be partly attributed to different fishing histories. Multiple-use zoning provides a means to identify and resolve conflicts and achieve what are likely universal objectives for fisheries sustainability and conservation. 相似文献
19.
Sea turtle bycatch to fish catch ratios for differentiating Hawaii longline-caught seafood products 总被引：1，自引：0，他引：1
Sea turtles can be incidentally caught in pelagic longline fishing gear targeting tuna and swordfish. Bycatch to fish catch (B/C) ratios can differentiate seafood based on sea turtle impacts. This study demonstrates the use of B/C ratios indexed to the weight of fish catch: (1) to report on the significant progress in reducing sea turtle bycatch in Hawaii's swordfish longline sector and (2) to compare Hawaii and other Pacific longline fisheries by number of sea turtle interactions per weight of catch. Hawaii's longline tuna fishery sets the benchmark of 1 sea turtle interaction per 190,000 kg of tuna caught. 相似文献
20.
《Marine Policy》2015
Catch data indicates that the world’s 25 largest marine capture fisheries have generally comprised some 40–50% of the total annual reported catch (1950–2012). From a game theory perspective, there is considerable diversity across these 25 fisheries, both in terms of the number of players and the management paradigms. Here, a dominance-oriented classification system is proposed, according to which fisheries are categorized into: (1) hegemonic systems with single-player dominance; (2) coupled systems with two-player dominance; (3) group systems with shared dominance; (4) systems with no dominant player. Among these categories, the fourth represents perhaps the greatest challenge to sustainable management, while also demonstrating the challenges of managing common pool marine ecosystem services in areas beyond national jurisdiction (ABNJ). The survey and analysis highlights how hegemonic conditions tend to preclude the establishment of cooperative agreements irrespective of the number of players involved in the fishery. Shifts in dominance away from hegemony, as demonstrated most recently in the case of the highly migratory Pacific Saury, can open the door to greater cooperation. Movement of fish stocks and displacement of fishing activities, due for example to climate change, have the capacity to cause major shifts in dominance and, in some cases, destabilize existing cooperative mechanisms. 相似文献