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1.
Current fisheries management is, unfortunately, reactive rather than proactive to changes in fishery characteristics. Furthermore, anglers do not act independently on waterbodies, and thus, fisheries are complex socio-ecological systems. Proactive management of these complex systems necessitates an approach--adaptive fisheries management--that allows learning to occur simultaneously with management. A promising area for implementation of adaptive fisheries management is the study of luring anglers to or from specific waterbodies to meet management goals. Purposeful manipulation of anglers, and its associated field of study, is nonexistent in past management. Evaluation of different management practices (i.e., hypotheses) through an iterative adaptive management process should include both a biological and sociological survey to address changes in fish populations and changes in angler satisfaction related to changes in management. We believe adaptive management is ideal for development and assessment of management strategies targeted at angler participation. Moreover these concepts and understandings should be applicable to other natural resource users such as hunters and hikers.  相似文献   

2.
A fuzzy adaptive management framework is proposed for evaluating the vulnerability of an ecosystem to losing ecological integrity as a result of climate change in an historical period (ex post evaluation) and selecting the best compensatory management action for reducing potential adverse impacts of future climate change on ecological integrity in a future period (ex ante evaluation). The ex post evaluation uses fuzzy logic to test hypotheses about the extent of past ecosystem vulnerability to losing ecological integrity and the ex ante evaluation uses the fuzzy minimax regret criterion to determine the best compensatory management action for alleviating potential adverse impacts of climate change on ecosystem vulnerability to losing ecological integrity in a future period. The framework accounts for uncertainty regarding: (1) the relationship between ecosystem vulnerability to losing ecological integrity and ecosystem resilience; (2) the relationship between ecosystem resilience and the extent to which observed indicators of ecological integrity depart from their thresholds; (3) the extent of future climate change; and (4) the potential impacts of future climate change on ecological integrity and ecosystem resilience. The adaptive management element of the framework involves using the ex post and ex ante evaluations iteratively in consecutive time segments of the future time period to determine if and when it is beneficial to adjust compensatory management actions to climate change. A constructed example is used to demonstrate the framework.  相似文献   

3.
Marine ecosystems are in serious troubles globally, largely due to the failures of fishery resources management. To restore and conserve fishery ecosystems, we need new and effective governance systems urgently. This research focuses on fisheries management in ancient China. We found that from 5,000 years ago till early modern era, Chinese ancestors had been constantly enthusiastic about sustainable utilization of fisheries resources and natural balance of fishery development. They developed numerous rigorous policies and regulations to guide people to act on natural laws. Being detailed and scientific, the legal systems had gained gratifying enforcement, due to official efforts and folks’ voluntary participation in resource management. In-depth analyses show that people’s consciousness of ecological conservation was derived from the edification of kinds of ancient eco-ethical wisdom, such as totemism, nature worship, Zhou Yi, Taoism, Buddhism, Confucianism, Mohism, etc. All this Chinese classical wisdom have the same cores: “Nature and Man in One” spirit, frugality and “All things are equal” concept. The findings show that eco-ethical thinking is never inconsistent with social ethic systems, and it’s of great importance to give legal effect to usual ecological moral claims and eco-ethical requirements of the public in protecting the environment. The eco-ethical wisdom is efficient in assisting and urging people to fulfill humans’ obligation for nature. Finally, it’s believed that present world fisheries management will benefit a lot from all these ancient Chinese thoughts and practices. People are expected to make the most of the eco-ethical wisdom, strengthen fishery legislation and fully stimulate their voluntary participation in both marine fishery resources conservation and fishery cyclic economy.  相似文献   

4.
Increased efforts to analyze the human dimensions of anglers are necessary to improve freshwater fisheries management. This paper is a comparative analysis of urban and rural anglers living in a metropolis, based on n = 1061 anglers responding to a mail survey in the German capital of Berlin. More than two thirds of the anglers (71%) had spent most (>50%) of their effort outside the city borders of Berlin and thus were categorized as rural anglers. Compared to the rural anglers, urban anglers (50% of total effort spent inside the city) were younger and less educated. Urban anglers were more avid and committed, less mobile, and more frequently fished from boats and during weekdays. Rural anglers were more experienced, fished for longer times per trip, fished more often at weekends and on holidays, were more often members of angling clubs, and more frequently caught higher valued fish species. The achievement and fish quantity aspects of the angling experience were more important for urban than for rural anglers. Concerning management options, urban anglers more frequently suggested constraining other stakeholders and reducing regulations, whereas rural anglers more often proposed improving physical access to angling sites. Future urban fishing programs should offer ease of access, connection to public transportation, moderate prices, and diverse piscivorous fish stocks. In contrast to rural fisheries, the provision of high ecological and aesthetical quality of the angling waters can be regarded as of minor importance in urban fisheries. Rural fisheries managers need to consider the needs of stakeholders living in Berlin to minimize impacts on the less degraded rural water bodies and potential user conflicts with resident anglers. Ecosystem-based management approaches should guide rural fisheries policy.  相似文献   

5.
Undamming Rivers: A Review of the Ecological Impacts of Dam Removal   总被引:26,自引:4,他引:22  
Dam removal continues to garner attention as a potential river restoration tool. The increasing possibility of dam removal through the FERC relicensing process, as well as through federal and state agency actions, makes a critical examination of the ecological benefits and costs essential. This paper reviews the possible ecological impacts of dam removal using various case studies. Restoration of an unregulated flow regime has resulted in increased biotic diversity through the enhancement of preferred spawning grounds or other habitat. By returning riverine conditions and sediment transport to formerly impounded areas, riffle/pool sequences, gravel, and cobble have reappeared, along with increases in biotic diversity. Fish passage has been another benefit of dam removal. However, the disappearance of the reservoir may also affect certain publicly desirable fisheries. Short-term ecological impacts of dam removal include an increased sediment load that may cause suffocation and abrasion to various biota and habitats. However, several recorded dam removals have suggested that the increased sediment load caused by removal should be a short-term effect. Preremoval studies for contaminated sediment may be effective at controlling toxic release problems. Although monitoring and dam removal studies are limited, a continued examination of the possible ecological impacts is important for quantifying the resistance and resilience of aquatic ecosystems. Dam removal, although controversial, is an important alternative for river restoration.  相似文献   

6.
A multivariate time series model is formulated to study monthly variations in municipal water demand. The left hand side variable in the multivariate regression model is municipal water demand (gallons per connection per day) and the right hand side contains (explanatory) variables which include price (constant dollars), average temperature, total precipitation, and percentage of daylight hours. The application of the regression model to Salt Lake City Water Department data produced a high multiple correlation coefficient and F-statistic. The regression coefficients for the right hand side variables all have the appropriate sign. In an ex post forecast, the model accurately predicts monthly variations in municipal water demand. The proposed monthly multivariate model is not only found useful for forecasting water demand, but also useful for predicting and studying the impact of nonstructural management decisions such as the effect of price changes, peak load pricing methods, and other water conservation programs.  相似文献   

7.
Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased 9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers’ participation in the management process increased and they benefited from increased monetary returns. Additionally, the number of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under conditions of uncertainty.  相似文献   

8.
A marked decline in the contribution by Marovo Lagoon to the annual total bêche-de-mer production of the Solomon Islands from 58% in 1989 to 17% in 2003 prompted investigation of their current biomass and diversity. We also assessed changes to critical ecological services and the prospects for population recovery following a fisheries closure. Day time and nocturnal transects revealed a mean abundance of 32.4 (SD = 5.3) low value species per ha (e.g. Holothuria atra, H. edulis, H. coluber and Thelenota anax) and 15.2 (SD = 2.7) high value species per ha (e.g. H. fuscogilva, Actinopyga lecanora, Stichopus hermanni and Thelenota ananas). Following a 17 month closure of the fishery (2005–2007), the abundance of bêche-de-mer was reported by local fisherman to have increased; however, no scientific studies were conducted that can substantiate this community held belief. The current study aimed to document the impact of re-opening the fishery in 2007 and documented a decline in high value species of 9% over a 5 month period following the opening of the fishery, while low value species continued to increase in abundance by 11%, over the same period based on nocturnal surveys. Continued observation of the recovery, post closure, and any subsequent harvest in Marovo will be required to properly understand population dynamics and provide a sustainable harvest plan for bêche-de-mer in the future.  相似文献   

9.
Building trust between resource users and natural resource institutions is essential when creating conservation policies that rely on stakeholders to be effective. Trust can enable the public and agencies to engage in cooperative behaviors toward shared goals and address shared problems. Despite the increasing attention that trust has received recently in the environmental management literature, the influence that individual cognitive and behavioral factors may play in influencing levels of trust in resource management institutions, and their associated scientific assessments, remains unclear. This paper uses the case of fisheries management in the northeast to explore the relationships between an individual’s knowledge of the resource, perceptions of resource health, and participatory experience on levels of trust. Using survey data collected from 244 avid recreational anglers in the Northeast U.S., we test these relationships using structural equation modeling. Results indicate that participation in fisheries management is associated with increased trust across all aspects of fisheries management. In addition, higher ratings of resource health by anglers are associated with higher levels of trust of state and regional institutions, but not federal institutions or scientific methods.  相似文献   

10.
Mixed findings emerge from this ex post Cost-Benefit Analysis of a major water investment programme in Ireland. Water supply and conservation investments, where most benefits were internal, generally proved worthwhile. Wastewater investments could not be analysed fully due to lack of environmental data. Here the authors estimated the level of ‘willingness-to-pay’ that would have been required to ‘justify’ the investments. In some cases the required level seemed implausibly high, raising questions as to prioritisation of projects. The authors recommend a more systematic approach to recording environmental benefits in future investment programmes, the next likely wave being in new EU member states seeking to meet environmental standards. The EU, as likely co-funder of these investments, should require systematic recording of environmental benefits.  相似文献   

11.
Summary Many Third World Countries (TWCs), like Ghana, have not concerned themselves seriously with environmental problems as part of the entire socio-economic development process, until recently. This, for example, can be seen in their environmental policies and the rate at which these now are being made. Not only are environmental issues being considered in the formulation and implementation of new development programmes and projects, but it is being realised that earlier implemented projects need some evaluation,ex post, for possible, correction of past mistakes or, at least, as a source of self-containment. Thus, there has been interest in the impact assessment of past macro-projects as agricultural and resettlement schemes.An attempt is made to apply a simple matrices methodology to theex post evaluation of the Kpong Hydro-electric Project resettlement aspect, based on identified project and environment components. The results show that the impact on the socio- economic life of the settlers is positively greater than the physical and biological impacts. But considering other elements of the programme package and taking a perspective view, the settlers are after all, no better off. In view of the fact that a number of such schemes are now under consideration, it is useful for policy-makers and planners to learn from these lessons.Sam Ofori-Cudjoe is a Lecturer in Geography at the University of Cape Coast, Ghana. He is currently studying planning research at the Centre for Planning, University of Strathclyde, Glasgow. He obtained a BA (Hons) in Geography from the Department of Geography, University of Ghana, Legon, in 1978, and a MSc (Regional Planning) from the Department of Planning, University of Science and Technology (UST), Kumasi, Ghana, in 1981.  相似文献   

12.
ABSTRACT: Over 76,000 dams have been constructed on American rivers to provide services such as flood protection, water storage, hydroelectric power, and navigation. Although most dams continue to provide sufficient benefits to retain the structure, dam removal is becoming increasingly common. This study involved the construction of a dam removal database to analyze spatial and temporal trends in dam removal. The data included information on 417 cases of dismantled American dams, 153 with known rationales for removal. Database analysis indicated that the leading purposes for dismantling structures are safety concerns and interest in environmental restoration. There is substantial geographic variability in dam removal rationales, with California leading in razing dams for environmental purposes, and Wisconsin leading in economic and safety rationales. States with substantial removals tend to have programs that support and fund dam razing. Although removals for safety reasons have been increasing steadily in the past three decades, environmental removals made a rather dramatic and sudden entry into the dam removal arena in the 1990s. Analysis of spatial and temporal trends in dam razing are of particular significance given the likely increase in dam removals in the 21st Century.  相似文献   

13.
Kibler, Kelly, Desiree Tullos, and Mathias Kondolf, 2011. Evolving Expectations of Dam Removal Outcomes: Downstream Geomorphic Effects Following Removal of a Small, Gravel‐Filled Dam. Journal of the American Water Resources Association (JAWRA) 1‐16. DOI: 10.1111/j.1752‐1688.2011.00523.x Abstract: Dam removal is a promising river restoration technique, particularly for the vast number of rivers impounded by small dams that no longer fulfill their intended function. As the decommissioning of small dams becomes increasingly commonplace in the future, it is essential that decisions regarding how and when to remove these structures are informed by appropriate conceptual ideas outlining potential outcomes. To refine predictions, it is necessary to utilize information from ongoing dam removal monitoring to evolve predictive tools, including conceptual models. Following removal of the Brownsville Dam from the Calapooia River, Oregon, aquatic habitats directly below the dam became more heterogeneous over the short term, whereas changes further downstream were virtually undetectable. One year after dam removal, substrates of bars and riffles within 400 m downstream of the dam coarsened and a dominance of gravel and cobble sediments replaced previously hardpan substrate. New bars formed and existing bars grew such that bar area and volume increased substantially, and a pool‐riffle structure formed where plane‐bed glide formations had previously dominated. As the Brownsville Dam stored coarse rather than fine sediments, outcomes following removal differ from results of many prior dam removal studies. Therefore, we propose a refined conceptual model describing downstream geomorphic processes following small dam removal when upstream fill is dominated by coarse sediments.  相似文献   

14.
Fee-fishing involves paying a fee for the privilege of fishing a body of water where fish populations are enhanced by stocking fish. Past literature on this activity has focused more on the operation of the enterprise and management of the fish than the people and site characteristics. The objectives of the study were to profile anglers and describe their site/management preferences. This study utilized an on-site interview and mail-back questionnaire at fee-fishing establishments in West Virginia (n = 212). Factor analysis of desired recreation experiences yielded five factors: Experience nature & adventure, Stress release & relaxation, Trophy fishing, Escape, and Family time. Cluster analysis showed that these anglers can be segmented into two distinct clusters, differing by sociodemographic characteristics, fishing behavior, and site/management preferences. The findings from this study provide baseline data to aid public resource managers and fee-fishing business owners in determining how to provide satisfying outdoor experiences and deliver desired services on-site. Future research will be needed from additional fee-fishing sites to obtain more detail about this outdoor recreation cohort and be able to generalize to a larger population of participants.  相似文献   

15.
16.
Uncertainties inherent in fisheries motivate a precautionary approach to management, meaning an approach specifically intended to avoid bad outcomes. Stochastic dynamic optimization models, which have been in the fisheries literature for decades, provide a framework for decision making when uncertain outcomes have known probabilities. However, most such models incorporate population dynamics models for which the parameters are assumed known. In this paper, we apply a robust optimization approach to capture a form of uncertainty nearly universal in fisheries, uncertainty regarding the values of model parameters. Our approach, developed by Nilim and El Ghaoui (Oper Res 53(5):780–798, 2005), establishes bounds on parameter values based on the available data and the degree of precaution that the decision maker chooses. To demonstrate the applicability of the method to fisheries management problems, we use a simple example, the Skeena River sockeye salmon fishery. We show that robust optimization offers a structured and computationally tractable approach to formulating precautionary harvest policies. Moreover, as better information about the resource becomes available, less conservative management is possible without reducing the level of precaution.  相似文献   

17.
This paper combines narrative and policy performance analyses to explore why resource management is contentious even when resources are increasing in abundance. Employing a case study of red drum in North Carolina, the study aimed to find out how different narratives of fishery science interact with policy performances to create outcomes that exacerbate conflicts. Examining six years of fisheries governance, the study explores how policy performances shape managers’ interpretations of fisheries science and modes of interacting with each other. The study finds that despite being a so-called success story, red drum management remains controversial because while user groups are concerned about access and allocation questions, managers focus on debating the meaning and implications of scientific data. Though compromises between user groups are made, conflict continues because the process through which they are reached creates frustration rather than understanding. That resource access dilemmas remain so prominent confirms that continually increasing scientific information has done little to solve resource conflicts, a key point in the dawning era of ‘big data'. The findings underscore the need for more scrutiny of how policy-making is performed, to provide insight into where interventions might promote better collaboration and acceptance of compromises.  相似文献   

18.
Saltwater fishing tournaments in the United States are generally not regulated nor are there different fishing regulations for tournament and nontournament anglers. Although much is known about those who participate in fishing tournaments in terms of their fishing motivations, attitudes, and characteristics, much less is known at the angler population level regarding their preferences for tournament opportunities. Using a stated preference choice model with hypothetical scenarios to simulate participation choices and understand preferences, study objectives were to identify angler preferences for various types of tournament fishing “products.” Four tournament policy characteristics were investigated: promotion of catch and release, bait restrictions, whether a percentage of the tournament entrance fee should go to support fishery management activities, and whether a tournament should be a nonprofit or profit-making venture. Three expectation attributes were inserted: tournament size, trip cost per day, and whether a tournament is family friendly. We sent seven different versions of the mail questionnaire to 1,633 anglers. Of 795 returns, 648 were used for estimating conditional logit models. Analysis indicated that a scenario with no management interventions was not most preferred. Anglers most preferred a conservation-oriented option that introduced additional management measures. Overall, scenarios with management interventions were more favored than the status quo situation (with no management interventions). Although respondents showed reluctance to adopt other management-related options, results generally indicated they were increasingly concerned with sustainability of fish stocks and potential conflicts between tournament and nontournament users and preferred tournament products that reflect these concerns.  相似文献   

19.
The 4-year drawdown of Horsetooth Reservoir, Colorado, for dam maintenance, provides a case study analog of vegetation response on sediment that might be exposed from removal of a tall dam. Early vegetation recovery on the exposed reservoir bottom was a combination of (1) vegetation colonization on bare, moist substrates typical of riparian zones and reservoir sediment of shallow dams and (2) a shift in moisture status from mesic to the xeric conditions associated with the pre-impoundment upland position of most of the drawdown zone. Plant communities changed rapidly during the first four years of exposure, but were still substantially different from the background upland plant community. Predictions from the recruitment box model about the locations of Populus deltoides subsp. monilifera (plains cottonwood) seedlings relative to the water surface were qualitatively confirmed with respect to optimum locations. However, the extreme vertical range of water surface elevations produced cottonwood seed regeneration well outside the predicted limits of drawdown rate and height above late summer stage. The establishment and survival of cottonwood at high elevations and the differences between the upland plant community and the community that had developed after four years of exposure suggest that vegetation recovery following tall dam removal will follow a trajectory very different from a simple reversal of the response to dam construction, involving not only long time scales of establishment and growth of upland vegetation, but also possibly decades of persistence of legacy vegetation established during the reservoir to upland transition.  相似文献   

20.

There is a growing recognition that knowledge of indigenous communities, based on accumulated observations and experience over time, is significant for sustainable environmental management in collaboration with modern scientific knowledge. A number of innovative policy initiatives are currently being implemented in New Zealand to enable indigenous Maori tribes and sub-tribes to rehabilitate and manage their local fisheries in accordance with customary values and practices. These policies are an important milestone from an historical perspective as they are meant to recognise and empower the role of Maori as Treaty partners. The fisheries management regime in New Zealand now provides for Maori representation at the local level within a co-management framework that enables local Maori communities to exercise their customary rights. These institutional arrangements have been crafted to facilitate Maori input, based on customary values and practices, to complement modern Western management practices for sustainable harvesting of marine resources. Nevertheless, the degree to which these initiatives constitute an adequate response to Maori Treaty aspirations is debatable. A major constraint in this respect is that the government is compelled to recognise the needs of other, economically and politically more dominant, non-Maori user-groups in allocating and managing access to fishery resources and the marine environment.  相似文献   

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