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1.
Many believe commercial fisheries in Alaska (U.S.A.) are sustainability success stories, but ongoing socioeconomic problems across the state raise questions about how this sustainability is being defined and evaluated. Problems such as food insecurity and the disenfranchisement of Alaska Natives from fishing rights are well documented, yet these concerns are obscured by marketing campaigns that convey images of flourishing fishing communities and initiatives to certify Alaska's fisheries as responsibly managed. Fisheries management mandates and approaches built on such metrics and technologies as maximum sustainable yield and systems of tradable quotas actually serve to constrain, circumscribe, and marginalize some Alaskans’ opportunities for effecting change in how the benefits of these fisheries are allocated. Beneath the narrative of sustainability, these management technologies perpetuate a cognitive ecological model of sustainability that is oriented to single‐species outcomes, that casts people as parasites, and thus assumes the necessity of trade‐offs between biological and social goals. Alternative cognitive models are available that draw metaphors from different ecological concepts such as keystone species and mutualisms. Such models, when used to inform management approaches, may improve societal outcomes in Alaska and elsewhere by promoting food security and sustainability through diversified natural resource harvest strategies that are more flexible and responsive to environmental variability and change. Perspectivas Alternativas sobre la Sustentabilidad de las Pesquerías Comerciales en Alaska  相似文献   

2.
Since fishery resources are regarded as an important source of income and food security, these resources need to be protected and conserved for sustainable use. To do this, the government of Cambodia has revised its policies, shifting management and responsibility to the local level. In response to government policy, Krala Peah village community fishery was established to manage resources within the area. The purpose of this study was to assess the outcome of community fishery management. Moreover, community fishery management was assessed through face-to-face interview and a participatory approach. The major findings of this study indicate that community fishery has led to a more equitable and efficient fishery within Krala Peah village. Although it has not led to improvements in fishing habitats and fish catch, it has reduced some factors that adversely affected sustainability. Furthermore, it has caused a reduction in illegal fishing, which was the main objective of the fishers.  相似文献   

3.
An overarching challenge of natural resource management and biodiversity conservation is that relationships between people and nature are difficult to integrate into tools that can effectively guide decision making. Social–ecological vulnerability offers a valuable framework for identifying and understanding important social–ecological linkages, and the implications of dependencies and other feedback loops in the system. Unfortunately, its implementation at local scales has hitherto been limited due at least in part to the lack of operational tools for spatial representation of social–ecological vulnerability. We developed a method to map social–ecological vulnerability based on information on human–nature dependencies and ecosystem services at local scales. We applied our method to the small‐scale fishery of Moorea, French Polynesia, by combining spatially explicit indicators of exposure, sensitivity, and adaptive capacity of both the resource (i.e., vulnerability of reef fish assemblages to fishing) and resource users (i.e., vulnerability of fishing households to the loss of fishing opportunity). Our results revealed that both social and ecological vulnerabilities varied considerably through space and highlighted areas where sources of vulnerability were high for both social and ecological subsystems (i.e., social–ecological vulnerability hotspots) and thus of high priority for management intervention. Our approach can be used to inform decisions about where biodiversity conservation strategies are likely to be more effective and how social impacts from policy decisions can be minimized. It provides a new perspective on human–nature linkages that can help guide sustainability management at local scales; delivers insights distinct from those provided by emphasis on a single vulnerability component (e.g., exposure); and demonstrates the feasibility and value of operationalizing the social–ecological vulnerability framework for policy, planning, and participatory management decisions.  相似文献   

4.
Mangrove forests constitute a pantropical ecosystem that has been much misused and mismanaged, without regard for actual and potential value to coastal resources. This paper uses primary and secondary data sources to assesses the economic value and pollution problems affecting a mangrove ecosystem. It concludes that this fragile ecosystem is under increasing biological stress resulting from industrial, agro-industrial, fishing and urban activities because both the private and public sector regard this ecosystem as wasteland. The paper concludes that, in order to achieve sustainability of the remaining forest, there is need for financial evaluation of the potentials of this ecosystem. Finally, the study identifies sustainable development and management options for mangrove forest and challenges scientists, researchers, natural resource managers and mangrove biologists to provide government authorities and society with evidence of the true potentials of mangrove ecosystems.  相似文献   

5.
Abstract: The Tiwi people of northern Australia have managed natural resources continuously for 6000–8000 years. Tiwi management objectives and outcomes may reflect how they gather information about the environment. We qualitatively analyzed Tiwi documents and management techniques to examine the relation between the social and physical environment of decision makers and their decision‐making strategies. We hypothesized that principles of bounded rationality, namely, the use of efficient rules to navigate complex decision problems, explain how Tiwi managers use simple decision strategies (i.e., heuristics) to make robust decisions. Tiwi natural resource managers reduced complexity in decision making through a process that gathers incomplete and uncertain information to quickly guide decisions toward effective outcomes. They used management feedback to validate decisions through an information loop that resulted in long‐term sustainability of environmental use. We examined the Tiwi decision‐making processes relative to management of barramundi (Lates calcarifer) fisheries and contrasted their management with the state government's management of barramundi. Decisions that enhanced the status of individual people and their attainment of aspiration levels resulted in reliable resource availability for Tiwi consumers. Different decision processes adopted by the state for management of barramundi may not secure similarly sustainable outcomes.  相似文献   

6.
Establishing marine protected areas (MPAs) helps to restore and sustain marine and fishery resources, but in the Philippines only 20% of total MPAs are achieving their management objectives. We conducted a case study of a small MPA in Northern Philippines to understand socio-economic status and livelihoods of the fishermen stakeholders, and examine their attitudes and perceptions on marine resource values and conservation. Using an ordered probit model, we also investigated factors affecting these perceptions. We found a lower fish income ratio in higher income quartiles, a small share of local non-fishery income, and an apparent lack of other livelihood opportunities within the rural economy. The majority of fishermen had positive perceptions of the non-market value of marine resources, agreed with the need for MPAs, and perceived positive potential income benefit from MPAs. Level of education and fishing income were consistent significant positive determinants of these perceptions. Policy implications suggest: involving likely-to-be-displaced reef fishers in the crafting of management plans; conducting intensive research on appropriate and feasible livelihood options, for example, marine culture technologies; and designing explicit strategies to increase the propensity of coastal households to invest in children's education as a strategy for long-term sustainability of resource management.  相似文献   

7.
For many decades, fisheries research has focused on stock assessment and the impact of the fishery effort on resources. Although this knowledge remains necessary, a more integrated analysis of the joint dynamics of resource and operational activities is needed to provide more useful advice for the management of fishery systems. Since 1994 a new approach to fishery science has been carried out for Cameroonian small-scale fisheries, the aim being the incorporation into fishery science of research on fishery management, fishing processes and fishermen's behaviour. This paper presents a more systemic data approach which combines biological parameters and operational factor analyses with the goal of sustainable development. From two years of data collected on the purse seine fishing units operating in the Bay of Biafra (2002 and 2003), a set of three correspondence analyses is applied: (1) to the length frequency distribution of Ethmalosa fimbriata, (2) to the number of visits per fishing ground, and (3) to the species appearance frequency in the landings. These three analyses were plotted per month-year period. The results are presented in the form of an annual exploitation cycle, linking fishing grounds, the main species caught, and corresponding fishing period.  相似文献   

8.
Economics of the fishery has focused on the wastefulness of common pool resource exploitation. Pure open access fisheries dissipate economic rents and degrade biological stocks. Biologically managed fisheries also dissipate rents but are thought to hold biological stocks at desired levels. We develop and estimate an empirical bioeconomic model of the Gulf of Mexico gag fishery that questions the presumptive success of biological management. Unlike previous bioeconomic life history studies, we provide a way to circumvent calibration problems by embedding our estimation routine directly in the dynamic bioeconomic model. We nest a standard biological management model that accounts for complex life history characteristics of the gag. Biological intuition suggests that a spawning season closure will reduce fishing pressure and increase stocks, and simulations of the biological management model confirm this finding. However, simulations of the empirical bioeconomic model suggest that these intended outcomes of the spawning closure do not materialize. The behavioral response to the closure appears to be so pronounced that it offsets the restriction in allowable fishing days. Our results indicate that failure to account for fishing behavior may play an important role in fishery management failures.  相似文献   

9.
The interaction between multiple stressors on Caribbean coral reefs, namely, fishing effort and hurricane impacts, is a key element in the future sustainability of reefs. We develop an analytic model of coral-algal interactions and explicitly consider grazing by herbivorous reef fish. Further, we consider changes in structural complexity, or rugosity, in addition to the direct impacts of hurricanes, which are implemented as stochastic jump processes. The model simulations consider various levels of fishing effort corresponding to' several hurricane frequencies and impact levels dependent on geographic location. We focus on relatively short time scales so we do not explicitly include changes in ocean temperature, chemistry, or sea level rise. The general features of our approach would, however, apply to these other stressors and to the management of other systems in the face of multiple stressors. It is determined that the appropriate management policy, either local reef restoration or fisheries management, greatly depends on hurricane frequency and impact level. For sufficiently low hurricane impact and macroalgal growth rate, our results indicate that regions with lower-frequency hurricanes require stricter fishing regulations, whereas management in regions with higher-frequency hurricanes might be less concerned with enhancing grazing and instead consider whether local-scale restorative activities to increase vertical structure are cost-effective.  相似文献   

10.
This paper reports a study of costs and benefits of Coral Triangle Initiatives (CTI) and Mangrove Rehabilitation Projects (MRP) in the Solomon Islands. It was observed that the communities have different attitudes and perceptions toward climate change challenges. The different scales and magnitudes of climate change impacts that are perceived at these sites, and the different subsistence realities make them have varied responses and points of view regarding such impacts. For instance, respondents from Oibola experienced the most adverse impacts from climatic change events compared to those living in the Naro and Sairaghi sites. Introduction of CTI and MRP has driven the villagers to travel out far from their traditional fishing grounds to catch enough fish to sell and support their families. This implies higher fishing costs and time for commute. From a social perspective, this weakens the communal bond in the community. In spite of these trade-offs, the respondents expressed satisfaction with the level of benefits received from the projects, which included the rehabilitation of the ecosystems and breeding grounds for fish and habitats around the area. We mapped the costs and benefits of these projects to the villagers, and although no amounts or figures were disclosed, the benefits are compared against corresponding costs. One key factor for the success of the initiatives was the cooperation and involvement of recipient villagers, and even including the management MPAs.  相似文献   

11.
Common-pool governance principles are becoming increasingly important tools for natural resource management with communities and comanagement arrangements. Effectiveness of these principles depends on variability in agreements, trust, and adherence to institutional norms. We evaluated heterogeneity in governance principles by asking 449 people in 30 fishing communities in 4 East African countries to rate their effectiveness. The influences of individuals, their membership and role in stakeholder community groups, leadership, community, and country were tested. The membership and role of people were not the main influence on their perceptions of the effectiveness of governance principles. Therefore, drawing conclusions about the effectiveness of specific principles would be difficult to make independent of the individuals asked. More critical were individuals’ nationalities and their associations with the shared perceptions of a response-group's effectiveness of each principle. Perceptions of effectiveness differed strongly by country, and respondents from poor nations (Madagascar and Mozambique) were more cohesiveness but had fewer and weaker between-community conflict-resolution mechanisms. Overall, group identity, group autonomy, decision-making process, and conflict resolution principles were perceived to be most effective and likely to be enforced by repeated low-cost intragroup activities. Graduated sanctions, cost–benefit sharing, and monitoring resource users, fisheries, and ecology were the least scaled principles and less affordable via local control. We suggest these 2 groups of principles form independently and, as economies develop and natural resources become limiting, sustainability increasingly depends on the later principles. Therefore, management effectiveness in resource-limited situations depends on distributing power, skills, and costs beyond fishing communities to insure conservation needs are met.  相似文献   

12.
China's Du Jiang Yan Irrigation Project, dating back to 256 BC, is one of the world's earliest water resources projects. Although it has been benefiting the Sichuan Basin area for over 2000 years, it is facing increasing problems due to ecological deterioration, over-exploitation from local industries and agriculture, suboptimal resource allocation arising from supply and demand mismatches, and an aging infrastructure. The traditional water resources development model is no longer appropriate for current and future needs of the area. Therefore, a sustainable development framework is envisioned in which population, economy and environment coexist in harmony. Within this framework, major strategies, such as construction and renovation of infrastructure, promotion of water conserving irrigation through non-engineering measures, pollution control and ecological improvements, restructuring of management entities and exploration of new funding sources, are proposed. An evaluation system is also introduced to assess the degree of sustainability and to monitor progress towards a high level of sustainable development.  相似文献   

13.
The fishing practices in the oligotrophic Lake Toya, Hokkaido, Japan, have profound implications in the ecosystem sustainability. The status of the sockeye salmon (Oncorhynchus nerka) population has become a serious concern among the lake managers and policy makers during the last decades. While the decline of the sockeye salmon population has been well documented in Lake Toya, there is considerable uncertainty with regards to the impact on the broader system dynamics. In this study, our objective is to address this knowledge gap by undertaking a synthesis of the Lake Toya food web using the mass-balance modeling software Ecopath with Ecosim (EwE). Our primary research question is to examine the repercussions of the declining sockeye salmon population on the trophic dynamics of the lake. Namely, we assess if there are any competing species that might have benefited from the decrease of sockeye salmon standing biomass and to what extent do these changes propagate through the Lake Toya food web? Our analysis pinpoints the critical role of the Japanese smelt (Hypomesus transpacificus nipponensis) in the system, which demonstrates a wide range of effects on several functional groups at both higher and lower trophic levels in Lake Toya. In particular, being a substantial portion of the masu salmon (Oncorhynchus masou) and adult sockeye salmon diets, the Japanese smelt has a positive impact on the top predators of the system. Amphipods, insects, and shrimp strongly benefit from the autochthonous and allochthonous organic matter in the system, while the tight coupling between phytoplankton and zooplankton seems to be particularly critical for the integrity of the Lake Toya food web. Whereas the values of the different ecosystem attributes (e.g., primary production/biomass, biomass/total throughput, system omnivory index, amount of recycled throughput, Finn's cycling index) provide evidence that Lake Toya is an immature system, we note that the internal redundancy and the system overhead estimates suggest that the lake possesses substantial reserves to overcome external perturbations. We also examined the effects of a variety of fishing policies on the biomass of masu salmon and adult sockeye salmon, which verify the belief that the adult sockeye population is quite fragile with high likelihood to collapse. Our analysis also predicts that sockeye will not rebound unless the fishing pressure exerted is substantially reduced (>50% of the reference levels used). Masu salmon seems to benefit under all the scenarios examined indicating that the intensity of the current fishing activities is significantly lower than its biomass accumulation rate in the system.  相似文献   

14.
Mapping and predicting the potential risk of fishing activities to large marine protected areas (MPAs), where management capacity is low but fish biomass may be globally important, is vital to prioritizing enforcement and maximizing conservation benefits. Drifting fish aggregating devices (dFADs) are a highly effective fishing method employed in purse seine fisheries that attract and accumulate biomass fish, making fish easier to catch. However, dFADs are associated with several negative impacts, including high bycatch rates and lost or abandoned dFADs becoming beached on sensitive coastal areas (e.g., coral reefs). Using Lagrangian particle modeling, we determined the potential transit of dFADs in a large MPA around the Chagos Archipelago in the central Indian Ocean. We then quantified the risk of dFADs beaching on the archipelago's reefs and atolls and determined the potential for dFADs to pass through the MPA, accumulate biomass while within, and export it into areas where it can be legally fished (i.e., transit). Over one-third (37.51%) of dFADs posed a risk of either beaching or transiting the MPA for >14 days, 17.70% posed a risk of beaching or transiting the MPA for >30 days, and 13.11% posed a risk of beaching or transiting the MPA for >40 days. Modeled dFADs deployed on the east and west of the perimeter were more likely to beach and have long transiting times (i.e., posed the highest risk). The Great Chagos Bank, the largest atoll in the archipelago, was the most likely site to be affected by dFADs beaching. Overall, understanding the interactions between static MPAs and drifting fishing gears is vital to developing suitable management plans to support enforcement of MPA boundaries and the functioning and sustainability of their associated biomass.  相似文献   

15.
Abstract:  Fishers, scientists, and resource managers have made substantial progress in reducing bycatch of sea turtles, seabirds, and marine mammals through physical modifications to fishing gear. Many bycatch-avoidance measures have been developed and tested successfully in controlled experiments, which have led to regulated implementation of modified or new fishing gear. Nevertheless, successful bycatch experiments may not translate to effective mitigation in commercial fisheries because experimental conditions are relaxed in commercial fishing operations. Such a difference between experimental results and real-world results with fishing fleets may have serious consequences for management and conservation of protected species taken as bycatch. We evaluated preimplementation experimental measures and postimplementation efficacy from primary and gray literature for three case studies: acoustic pingers that warn marine mammals of the presence of gill nets, turtle excluder devices that reduce bycatch of turtles in trawls, and various measures to reduce seabird bycatch in longlines. Three common themes to successful implementation of bycatch reduction measures are long-standing collaborations among the fishing industry, scientists, and resource managers; pre- and postimplementation monitoring; and compliance via enforcement and incentives.  相似文献   

16.
Abstract:  The emerging world crisis created by declining fish stocks poses a challenge to resource users and managers. The problem is particularly acute in poor nations, such as those in East Africa, where fishing is an important subsistence activity but high fishing intensity and use of destructive gear have resulted in declining catches. In this context developing effective management strategies requires an understanding of how fishers may respond to declines in catch. We examined the readiness of 141 Kenyan fishers to stop fishing under hypothetical scenarios of declines in catch and how socioeconomic conditions influenced their decisions. As expected, the proportion of fishers that would exit the fishery increased with magnitude of decline in catch. Fishers were more likely to say they would stop fishing if they were from households that had a higher material style of life and a greater number of occupations. Variables such as capital investment in the fishery and the proportion of catch sold had weak, nonsignificant relationships. Our finding that fishers from poorer households would be less likely to exit a severely declining fishery is consistent with the literature on poverty traps, which suggests the poor are unable to mobilize the necessary resources to overcome either shocks or chronic low-income situations and consequently may remain in poverty. This finding supports the proposition that wealth generation and employment opportunities directed at the poorest fishers may help reduce fishing effort on overexploited fisheries, but successful interventions such as these will require an understanding of the socioeconomic context in which fishers operate.  相似文献   

17.
Using a Pathways approach, controversies over environmental and natural resource management are viewed as expressions of alternative, or competing, pathways to sustainability. This supports deeper understanding of the underlying causes of natural resource management controversies. The framework is composed of two elements: the STEPS (Social, Technological, and Environmental Pathways to Sustainability) Pathways approach and frame analysis. Many sustainable development dilemmas are played out in specific places and consequently, the Pathways approach is integrated with a place-based frame analysis. The resulting framework guides empirical investigation in place-based contexts. This theorising about sustainability science can be used to cast light on contested natural resource management issues, in this case mining in northern Sweden. By exposing the range of alternative Pathways to critical norms of sustainable development, we ascertain whether action alternatives are compatible with sustainable futures. The framework provides a way in which sustainability science can better understand the origins of natural resource management conflicts, characterise the positions of the actors involved, identify the potential for cooperation between stakeholders leading to policy resolution and judge what Pathways help or hinder the pursuit of sustainable development. In addition, it can enhance sustainability science by guiding integrative sustainability research at the project scale.  相似文献   

18.
Artisanal fishing is an activity which has long occupied an important place on the West African coast. In less than 20 years, the increasingly widespread use of motors in fishing boats and cold storage facilities both on board and on land have enabled fishermen to master the constraints of space and time. Furthermore, globalization has created a demand for new products, thus influencing the behaviour of fishermen and consequently the status of some fish, turtle and marine mammal species. Development policies for artisanal fishing do not adequately reflect the importance of these changes. They tend to use inappropriate scales of reference, be it spatially (national borders take precedence over ecosystems) or temporally (the long-term consequences of development plans are seldom considered). Some international conservation organizations are testing promising new approaches to managing resources more sustainably and restoring degraded ecosystems, and their recent experiences can serve as useful examples to others. It is recommended to grant special rights of access to resident fishermen. In defending ‘their’ resources, they will also protect the ecological functions of the area. Close collaboration with administrations and development assistance agencies is needed to assess consequences of political decisions on the use of resources. The important role of marine protected areas as a tool for fishing management should be better documented and strengthened. These areas should not be considered as isolated units but rather as vital parts of a comprehensive system for improved coastal zone management. Consistent with the ecosystem approach, fishermen and their communities, being the main users of coastal resources, should also play a major role in the design and implementation of any fishing management actions.  相似文献   

19.
Harvest restrictions and stock enhancement are commonly proposed management responses for sustaining degraded fisheries, but comparisons of their relative effectiveness have seldom been considered prior to making policy choices. We built a population model that incorporated both size-dependent harvest restrictions and stock enhancement contributions to explore trade-offs between minimum length limits and stock enhancement for improving population sustainability and fishery metrics (e.g., catch). We used a Murray cod Maccullochella peelii peelii population as a test case, and the model incorporated density-dependent recruitment processes for both hatchery and wild fish. We estimated the spawning potential ratio (SPR) and fishery metrics (e.g., angler catch) across a range of minimum length limits and stocking rates. Model estimates showed that increased minimum length limits were much more effective than stock enhancement for increasing SPR and angler catches in exploited populations, but length limits resulted in reduced harvest. Stocking was predicted to significantly increase total recruitment, population sustainability, and fishery metrics only in systems where natural reproduction had been greatly reduced via habitat loss, fishing mortality was high, or both. If angler fishing effort increased with increased fish abundance from stocking efforts, fishing mortality was predicted to increase and reduce the benefits realized from stocking. The model also indicated that benefits from stock enhancement would be reduced if reproductive efficiency of hatchery-origin fish was compromised. The simulations indicated that stock enhancement was a less effective method to improve fishery sustainability than measures designed to reduce fishing mortality (e.g., length limits).  相似文献   

20.
Abstract:  The Chilean government has introduced a policy that gives formal property rights over defined areas of seabed to organized groups of artisanal fishers with the goal of achieving sustainable exploitation of natural resources. We assessed differences in the attitudes of participating artisanal fishers toward this form of management to understand their importance in the design and implementation of fisheries management. We used questionnaires and participatory rural appraisal techniques to survey members of six fishing management committees. Fishers' attitudes varied significantly among syndicates in three main domains: attitudes toward the environment, unresolved aspects behind the management area policy, and perceived benefits derived from adoption of the policy. These differences indicated the existence of distinct world views that structure fishers' behavior toward the marine environment and its management. In addition, the responses made by fishers correlated best with the degree of off-sector pluriactivity and their dependence on diving as a source of income. This suggested that a livelihood approach to the development of Chilean artisanal fisheries that considers the multiple economic niches of the fishers will be most effective in the implementation of dual conservation/management measures.  相似文献   

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