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1.
In recent decades, sea cucumber fisheries have rapidly expanded worldwide to meet rising demand in Asian markets. Catch trends have often followed a boom-and-bust trajectory and skyrocketing sea cucumber value has often spurred fishery development that outpaced adequate biological research for informed stock assessment. Currently, the dive fishery for Giant red sea cucumber (Parastichopus californicus) in British Columbia, Canada is considered moderately exploited. However, basic population parameters such as recruitment and mortality rates are still largely unknown, creating important sources of uncertainty in the fishery׳s stock assessment model. This study presents the results of an interview-based survey of experienced commercial harvesters׳ (1) perceptions of local trends in sea cucumber abundance, size, and fishing effort (CPUE), and (2) perceptions of management efficacy. The majority of harvesters perceived abundance (14/20) and CPUE (15/20) to have declined over their careers, and half of the harvesters reported decreased sea cucumber size. The harvesters most commonly cited overfishing as the most pressing problem facing the fishery (13/20), and the majority felt that Fisheries and Oceans Canada (DFO) needed to lower licence and/or area quotas to avoid further declines. Despite many knowledge gaps in the fishery, almost all harvesters (16/20) perceived that they are not adequately consulted and their concerns are not adequately considered by DFO. These results suggest a disjoint between DFO forecasts and perceived local sea cucumber trends, and highlight that the fishery may lack a resource-rights framework with adequate checks to decouple fishing pressure from increasing global market value and demand. Maintaining the long-term health of the BC sea cucumber fishery may depend on working more closely with harvesters to inform future management decisions and, ideally, moving towards a harvester-owned-and-operated licencing system that can better integrate the feedback that comes from attachment to place.  相似文献   

2.
Virginia supported the most productive bay scallop (Argopecten irradians) fishery in the United States in 1930, but the fishery disappeared three years later and never recovered. This collapse highlights a tipping point, but managers of extant bay scallop fisheries have not looked to this case for guidance, because the collapse has long been attributed to an exogenous eelgrass (Zostera marina) ‘wasting disease’ pandemic. Consequently, it remains little understood. However, efforts to restore the fishery, following successful eelgrass restoration, now warrant a thorough examination of its economic significance and disappearance. This study comprehensively surveyed information on the original fishery and reconstructed the pre-collapse population to evaluate restoration prospects and management strategies that reduce the risk of future scallop-seagrass system collapses. Harvest records suggest that overharvesting possibly contributed to the Virginia fishery disappearance—a factor that influenced other bay scallop fisheries but did not alarm contemporary managers in Virginia. The harvest peaked before managers observed eelgrass disappearing and exceeded most pre-collapse population estimates. Intensive dredging possibly precipitated a feedback that reduced scallop recruitment by lowering seagrass shoot densities. Managers should, therefore, consider a potential tradeoff between future scallop harvest and eelgrass restoration goals. The restored wild scallop population in Virginia cannot yet support a commercial fishery at historic levels, which removed between 270 and 380x as many individuals. However, the economic risks associated with reestablishing this fishery are low. The collapse did not cause a significant loss in total economic value, because harvesters rapidly shifted focus to clams, supplanting lost scallop revenue.  相似文献   

3.
This study investigated the interpretation and level of support of government regulations in Bahía de Kino, Sonora, one of the most important fishing communities in terms of diving extraction of benthic resources in the Northern Gulf of California. Research was conducted from April to August 2007, focusing on the small-scale fisheries sector of commercial divers. Information on fishers’ awareness of current policies, fishers’ attitudes concerning different aspects of fisheries regulation, and fishers' suggestions on how their fisheries should be managed, was gathered through structured interviews (including open and closed-ended questions), informal talks and participant observation. Results provide further evidence supporting the need for formally recognizing the fishers as key stakeholders in local fisheries, and for working cooperatively towards the design of management strategies and regulations that provide better stimulus for resource stewardship and discourage overfishing. Very importantly, this study suggests that there is strong support from resource users for implementing regulatory measures for local fisheries. Results could be used as a preliminary baseline to initiate the discussion among fishery stakeholders towards the development of species-specific management plans for the area, as required by the recently enacted fisheries act in Mexico, the “Ley General de Pesca y Acuacultura Sustentables”.  相似文献   

4.
《Marine Policy》2005,29(4):357-369
The effectiveness of the US Atlantic sea scallop fishery regulations has resulted in recovery from a biological standpoint. However, due to excessive harvest capability and regulatory inefficiencies, the industry is facing substantial harvesting costs and, hence, economic inefficiency. The main reason is that most regulations or restrictions do not take into account the fundamental importance of the property rights for inducing behavior more consonant with aggregate as well as individual rationality. This article conceptualizes the role and importance of property rights structures in their application to Atlantic sea scallop fishery management. Additionally, embryonic industry efforts in developing an enhancement program for this fishery may point to the need for more cooperative, area-based management strategies. By doing so, two important elements for achieving greater production and value from the scallop fishery are identified. First, establishing an ownership structure of private property rights in the form of Territorial User Rights in Fishing (TURFs) and second, having fishermen cooperate under an organizational structure, such as a harvesters’ cooperative. These elements imply that an alternative, rights-based cooperative approach may become a compatible governance arrangement and provide an incentive for the rational management of the scallop fishery.  相似文献   

5.
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   

6.
A pervasive argument has emerged in debates over US ocean fishery policy that the policy-making process has generally been captured by commercial industry interests and consequently permits fishing quotas beyond sustainable harvesting levels. While it is clear that commercial interests are over-represented relative to recreational interests on the regional councils that set fishery policy, it is not clear whether commercial interests necessarily enact unsustainable policies. This paper examines the vote choices of representatives on the Pacific Fisheries Management Council by creating a spatial map of ideal point locations of voting members during the years 2006-2009 and then identifying voting coalitions. If a dominance by commercial interests leads to unsustainable policies, then it must be the case that members of this interest group vote as a cohesive and distinct bloc. In the end, however, it is shown that a geographic explanation for vote choices outperforms an interest group explanation.  相似文献   

7.
This paper shows how post-oil spill management measures can affect the general pattern of fishing effort exerted on two particular species of great commercial value in northern Spanish fisheries: anglerfish (Lophius piscatorius and Lophius budegassa) and mackerel (Scomber scombrus). Data time series of catches and fishing efforts were analysed corresponding to the area and time period affected by the oil spill fishing restrictions (December 2002–June 2003) and similar previous and post-spill periods. This was done to detect shifts that could be due to either the oil spill per se or the management measures taken to minimise pollution effects. Then, analyses and simulations with Arcview GIS module FAST (Fishing Activity Simulation Tool v. 1.1) were carried out with the aim of studying the fishing effort spatial distribution. Changes were observed in the Catch Per Unit Effort (CPUE) of anglerfish and mackerel by area or fishery unit. Results show a spatial displacement of fishing effort to other fishing areas in the case of anglerfish, and the transfer of fishing effort between different fishery units in the case of mackerel. Although both effects were caused primarily by the management measures in force after the oil spill, they are considered side or collateral effects. The management measures that have to be taken after any disaster should also consider these kinds of ancillary effects as well as evaluating the likely positive or negative impact of these side effects.  相似文献   

8.
The history, methods, problems and regulation of fishing of the last remaining large queen conch resource in the world, located on a Jamaican fishing bank, are examined. The fishery activities for the queen conch, Strombus gigas Linnaeus are briefly described with the main activities in the industrial sector which produce the bulk of the harvest, which is exported. There are a few large producers harvesting the single major fishing ground of Pedro Bank, southwest of Kingston. These fishers harvested at least 1500 t annually between 1992 and 1998. Management is by licensing, individual quotas and a close season from July to October. Regulations related to CITES are thought to greatly assist in making licensed harvesters provide catch data to the Fisheries Division. The industrial operators have provided funding to undertake stock assessment studies in 1994 and again in 1997. We highlight the focus on management on a participatory consensual approach with meetings with all players in the industry. The conch fishery is thought to be one of the few areas of the Jamaica fishery where there is close and successful collaboration between fishers and the Fisheries Division. It provides an example of how rapid, precautionary, participatory action can provide an adequate basis for management until more definitive scientific information becomes available. The status of the conch fishery is thought to be sustainable at present, once reductions are made to the annual quota.  相似文献   

9.
Under what conditions can an aboriginal fishing community keep a commercial fishery closed because of persistent low stock abundance when the federal government insists on opening it to commercial fishing? This paper explores a decades long effort by the Haida Nation to protect local herring stocks on Haida Gwaii through a precautionary approach to commercial fishing, recently resulting in a Federal Court-granted injunction that prevented the Canadian Minister of Fisheries and Oceans from opening a commercial herring fishery on Haida Gwaii in 2015. The successful effort by the Haida Nation to protect herring stocks ultimately required a combination of strategies involving confrontation, negotiation and litigation that occurred across two management scales (local and coast-wide) and two levels of dispute resolution. Strategies were successful as a result of four key factors: (a) ongoing conservation concerns about probable harm to herring populations, (b) the existence of aboriginal rights that raises standards for federal government consultation and accommodation, (c) an existing negotiated co-management agreement between the Haida and Canada about the area where most herring stocks are located, and (d) strategic interactions among local and coast-wide forums where herring closures were debated.  相似文献   

10.
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   

11.
The paper presents the results of evaluation of compliance of the bag net fishery of Maharashtra coast, India with the relevant clauses of Article 7 (Fisheries management) of the Code of Conduct for Responsible Fisheries (CCRF). Questionnaire-based approach that covered ten categories of stakeholders responsible wholly or partially for the management of the bag net fishery was used in the present study. Evaluation of the Code revealed an overall compliance level of 67.52%. The study identified the critical areas of low compliance levels that require immediate attention. Though the bag net fishery is the most common and traditional fishery of Maharashtra that supports livelihood of several fishers, there is no specific policy to regulate, develop and ensure sustainability of the bag net fish resources. Therefore the Code could be taken as a reference document to facilitate responsible management of the bag net fishery taking the local conditions into account. The findings of the present study could be used as a diagnostic tool to help in suggesting measures to ensure sustainability of the bag net fishery resources achievable by making amendments to the fisheries policies of the State.  相似文献   

12.
The management and governance of shared stocks have long been identified as a challenge to achieve long-term sustainability in fisheries. This is the situation of fisheries in the Amazon basin, a region shared by nine countries. This paper provides an overview of the social-ecological outcomes and management implications of sharing fish stocks among countries with different public policies, taking the valuable Amazonian ornamental silver arawana (Osteoglossum bicirrhosum) trade as a case study. Specifically, it (i) presents and discusses the policies of Colombia, Peru and Brazil for the silver arawana fishery, and how these are conducive for the successful management of this shared transboundary fishery; and (ii) analyzes the market for the ornamental silver arawana and how it affects the ability to sustainably manage the fishery. The interplay between the multiple environmental, economic and social dimensions involved in the ornamental silver arawana fishery affects the sustainability of this species even in Brazil, where this fishing is forbidden but still illegally caught by Colombians and Peruvians. Among the factors that make fisheries policies inefficient in this region are: (i) incongruent policies between the countries and institutions with low organizational capacity to accomplish the established policies; (ii) environmental heterogeneity of Amazonian aquatic systems, which requires local and adaptive measures; and (iii) complex socio-economic relationships in the live-fish trade business. Legally binding efforts to reduce problems derived from shared fish stocks are an urgent need and should be addressed by the multilateral organizations created for the Amazonian sustainable development.  相似文献   

13.
The herring roe fishery in Canada's southern Gulf of St. Lawrence is a productive fishery that lies outside the confines of privatized arrangements. Yet, this fishery is compromised by its dependence on the Japanese seafood market. Consideration of the efficiency of this fishery needs to account for the role assumed by this market in setting fishing practices. A more ecologically and economically efficient use of the herring resource requires greater attention to supply chain integration by local harvesters, processors and buyers prior to engaging with distant markets. This is necessary regardless of the property rights regime that is in place.  相似文献   

14.
The spatial structure of fishery resources influences stock dynamics and finally the fishery. Therefore, this aspect should be included as a key topic in the assessment and management of fisheries. The fishery of the sea urchin Paracentrotus lividus in Galicia has been used as case study to demonstrate how the mismatch between biological, fishery and management scales causes failures in the governance, giving rise to over-exploitation. P. lividus is spatially distributed in nested biological units: patches, micro-stocks, local populations and metapopulations. Fishing operations are local exploiting micro-stocks; however management units in Galician comprise usually more than one local population. This pattern allows the depletion of several micro-stocks without any short-term signals in the exploitation rates over the complete managed territory. Management units should be redefined according to the boundaries of the local populations. In addition, the implementation of reserve networks or a rotation system could allow to effectively managing the resource at a fine-scale. Any of both regulations could also compensate the inverse density dependence that regulates recruitment and fecundity in this species.  相似文献   

15.
Tropical shrimp trawl fisheries are unsustainable, and similar sets of management measures are used globally to address the direct and indirect costs of their practices. Yet little is known about shrimp fishers’ perceptions, despite the clear importance of human behaviour in determining the success of fisheries management. This article presents the results of interviews with industrial shrimp trawl fishers from the southern Gulf of California, Mexico, and reveals fishers’ knowledge and attitudes that should be considered when developing management plans for industrial shrimp trawl fisheries. Fishers were asked to comment on problems facing the fishery, management options to address the issues, and the future of the fishery in general. The interviews also elicited new knowledge on effort and valuable components of bycatch, useful to the management process. Among the problems facing the Gulf of California fishery, fishers tended to identify those generated externally—fluctuations in shrimp populations, increases in fishing effort, decreases in shrimp prices and increasing overheads—and thus distance themselves from responsibility for management options. The successes of any mitigation measures for the fishery are likely to depend on proper enforcement and reliable governance, as our study indicates. Should strong enforcement be put in place, then trawl free areas seem to be the most pragmatic way to alleviate problems associated with the fishery; our effort data point to areas that might have greatest acceptance among fishers. A reduction in capacity would clearly complement marine zoning for trawl free areas. In the long run, however, it may be economic extinction of the fishery that reduces pressure on the marine ecosystem.  相似文献   

16.
《Ocean & Coastal Management》2006,49(5-6):332-341
Jamaica's industrial fishery for queen conch (Strombus gigas) has produced a substantial amount of much-needed foreign exchange and for at least 10 years has been the most valuable component of all commercial marine fisheries activities. Since its inception in 1990 it has grown tremendously and may now be at some risk of collapse, due to problems including, among other factors, overfishing, poor enforcement, foreign poaching and under-reporting of catches. This paper examines and analyzes the problems relating to management of the conch fishery and speculates on its future. The main problems are overfishing by licensed fishers who take more than permitted, and serious poaching by industrial vessels mainly from Honduras, which exploit poor high seas enforcement by Jamaican authorities. For nearly two years the official fishery was closed due to legal issues. During closures, considerable foreign poaching occurred. The paper suggests that increased roles for the coast guard, continued quota reductions, and the Convention on International Trade in Endangered Species of Flora and Fauna (CITES), could be the best options for sustainability.  相似文献   

17.
The California spiny or red rock lobster, Panulirus interruptus, is an ecologically and economically important species that has been exploited since the 1800s. No previous study in California has assessed the impacts of the recreational or commercial lobster harvest. Before the 2003–04 commercial and recreational lobster seasons, we conducted a fishery‐independent trap survey at Santa Catalina Island to document the impact of the lobster fisheries on the size structure, abundance, and sex ratios of mature P. interruptus (>65 mm carapace length (CL)). We concurrently sampled a predominantly commercially fished area, a recreationally fished area, and a 23‐year‐old invertebrate no‐take (INT) reserve. Relative to the INT reserve, legal‐size lobsters in the recreational area were similar in CL, but 31% less abundant. Legal‐size lobsters in the commercial area were 8% smaller and 70% less abundant than those in the INT reserve. The sex ratio of legal‐size lobsters, although near 50:50 in the recreational and INT reserve areas, was male‐dominated (67:33) in the commercial area. Differences in CPUE and mean CL of sub‐legal lobsters in the recreational and commercial areas suggest that factors in addition to harvesting pressure may affect these populations. Total biomass of mature lobsters in the recreational and commercial areas was 92% and 45%, respectively, of biomass in the INT reserve. Fecundity in the recreational and commercial areas was 83% and 42%, respectively, of fecundity in the INT reserve. This study provides preliminary data for future ecological studies and fisheries management evaluations.  相似文献   

18.
The stalked barnacle Pollicipes pollicipes is a cirriped crustacean that lives on very exposed rocky shores. This barnacle is the most important economical resource on intertidal rocky shores of continental Portugal. It is highly prized as food and heavily exploited (professional and recreational fishery), but fishery data are scarce and do not estimate the real pressure upon this resource.Despite its socio-economic interest, specific regulations on this fishery are recent and different along the Portuguese coast. Four regions with different regulation can be identified: the marine reserve “Reserva Natural das Berlengas” (RNB) and the marine park “Parque Marinho Prof. Luiz Saldanha” (PMLS) (both in central Portugal); the natural park located in SW Portugal (“Parque Natural do Sudoeste Alentejano e Costa Vicentina”, PNSACV); and the rest of the coast.The main objective of the present study was to study the spatial patterns of percentage cover, biomass, density and size structure of P. pollicipes in areas with different exploitation regimes, including harvested areas and no-take areas. Additionally, variability between mid shore and low shore barnacles was also analysed.Seven areas were sampled with a variable number of sites (a total of 24) randomly sampled in each area during 2011. Photographs and image analysis (percentage cover) and destructive sampling (density, biomass and size) were used.In general, percentage cover, biomass and density were higher in mid shore when compared to low shore, namely in harvested areas. Low shore barnacles had a higher proportion of adults with moderate and high commercial value, while juveniles were relatively more abundant at mid shore.There were no consistent differences in the patterns of distribution and abundance of P. pollicipes among areas subject to different exploitation regimes. The most different area was the harvested area by professional fishers in RNB, where the highest biomass within the study was registered (mid shore, 7.7 kg·m 2). Barnacles within this area presented a higher proportion of adults with commercial value, while recruits and juveniles were relatively more abundant in other areas.The hypothesis of a highest percentage cover, density and biomass in the low shore of no-take sites was not supported.  相似文献   

19.
Although an important conservation tool, Marine Protected Areas sometimes fall short of intended goals; however, adaptive management can potentially improve their effectiveness. Efforts to develop an MPA in Gilbert Bay, Labrador, Canada, began in 1998 to protect the genetically distinct population of Atlantic cod (Gadus morhua) and its habitat. Population monitoring and research conducted in Gilbert Bay during 26 research trips over 14 years have documented significant population declines. The biomass declined by as much as 83% and research catch rates by 54% since Gilbert Bay became a MPA in 2005. Commercial fishing in adjacent waters was strongly correlated (Pearson correlation r=−0.87, p=0.002), with the declining trend in research catch rates. Tag recaptures from the commercial fishery (n=105) confirmed that fishing removed large adult Gilbert Bay cod that seasonally move outside the MPA. Evidence of the production of strong year classes even at low adult population levels indicate that the Gilbert Bay cod population has the potential to increase rapidly under appropriate adaptive management; thus improving MPA effectiveness. A relatively small change in the timing of commercial fishing in waters adjacent to the MPA would likely produce this result; however, inflexible MPA regulations, and poor co-ordination and agreement among differing fishery management processes and stakeholders has delayed the implementation of such a change.  相似文献   

20.
东海区底拖网渔业主要经济鱼类渔业生物学的初步研究   总被引:23,自引:0,他引:23  
根据1997~2000年东海区底拖网渔业资源调查资料,分析了18种主要经济鱼类的渔业生物学特征,运用体长频率法估算了von Bertalanffy生长参数、总死亡系数、自然死亡系数、捕捞死亡系数和开发率。结果表明,大部分鱼类已出现个体小型化,15种鱼类的开发率过高,处于超额开发状态,其中,4种为重度超额开发,开发率大于0.8,7种为中度超额开发,开发率介于0.7~0.8之间,4种为轻度超额开发,开发率为0.5~0.7。建议加强保护和管理,以利于鱼类资源的可持续利用。  相似文献   

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