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Emerging Adaptation Approaches for Climate-Ready Fisheries Management 全文
2014
Malin L. Pinsky | Nathan J. Mantua
By 2100, ocean waters are expected to be substantially warmer and more acidic than they are today, with profound effects on coupled social-ecological fisheries systems. Despite broad recognition of impacts from both anthropogenic climate change and natural climate variability, incorporating climate and acidification considerations into management approaches has been difficult. However, clear opportunities exist for fostering "climate-ready" fisheries management, as evidenced by emerging research and implementation experiences that we review here. Approaches now exist for integrating climate change and variability into monitoring, vulnerability assessments, stock assessments, spatial management, annual harvest limits, international agreements, and management of emerging fisheries. While uncertainty, limited understanding, and the increased complexity of these new considerations have delayed more widespread implementation to date, these factors do not change the reality of climate change impacts on living marine resources. We conclude that, despite ongoing research needs, fisheries management can substantially expand capacity to respond to a changing climate.
显示更多 [+] 显示较少 [-]Classical fisheries theory and inland (floodplain) fisheries management; is there need for a paradigm shift? lessons from the Okavango Delta, Botswana 全文
2014
Mosepele, Ketlhatlogile
This paper reviews the fisheries management question of inland (floodplain) systems in the developing world and proposes a paradigm shift in approach. Inland fisheries management is largely based on classical fisheries formulations derived on temperate freshwater and marine single-stock fisheries. The basic models to manage inland fisheries are based on steady state equilibrium models. However, inland, flood-pulsed fisheries are dynamic and driven by external factors which are incongruent with the classical approach. Therefore, adopting this management approach in inland, flood-pulsed fisheries has created a management conundrum because of the obvious fundamental differences that exist between these two systems. Marine fisheries contribute to the macroeconomic growth of fishing countries, inland fisheries from developing countries are largely focused on recreational activities, while inland (floodplain) fisheries are key sources of food and nutrition security for marginalized riparian communities in the developing world. This review also uses lessons from the Okavango Delta fishery to illustrate the uniqueness of floodplain fisheries and the management questions therein. One key debate highlighted in this review is that inland fisheries are a livelihood of the last resort for poor (and sometimes malnourished) communities. Management should therefore mainstream this value into management interventions, especially since a sustainable utilization of this resource can assist developing countries to achieve some of the MDG’s. The paper concludes with an argument of the need for a paradigm shift in inland fisheries management, where key factors such as enhanced data collection, co-management regimes based on “real” democratic principles constitute some of the germane attributes of fisheries management plans
显示更多 [+] 显示较少 [-]The Fate of Fisheries Oceanography: Introduction to the Special Issue 全文
2014
Steven J. Bograd | Elliott L. Hazen | Evan A. Howell | Anne B. Hollowed
What is Fisheries Oceanography? Fisheries oceanography can be broadly defined as study of the interaction between marine fish and their environments across multiple life-history stages. Traditional fisheries management approaches estimate population abundance levels as a function of the number of spawning adults without environmental or ecological input, but the field of fisheries oceanography has provided a framework to predict recruitment and define harvest strategies within an ecosystem context. By seeking to elucidate mechanistic relationships between fish species and their surrounding oceanic habitats, the field of fisheries oceanography aims to provide a solid understanding of fish behavior, population dynamics, and life history with an ecosystem perspective.
显示更多 [+] 显示较少 [-]Land‐use impacts on small‐scale Mpologoma wetland fishery, eastern Uganda: A socio‐economic perspective 全文
2014
Ssanyu, Grace A. | Kipkemboi, Julius | Mathooko, Jude M. | Balirwa, John
Small‐scale fisheries in developing countries are characterized by uncertain futures attributable to ever‐increasing pressures on wetland resources. Data on the interconnectivity between wetland fishery, land‐use changes and the socio‐economic situation in the Mpologoma wetland, Uganda, were obtained through interviews and structured questionnaire surveys at sampling sites exhibiting differing different levels of environmental disturbance (ranging from less disturbed to highly disturbed). Rice production was the major economic activity at the highly disturbed sites, while maize production was the major activity at the less‐disturbed sites. Of the secondary activities, the Clarias gariepinus (Burchell, 1815) and Protopterus aethiopicus (Heckel, 1851) fishery was more important at the less‐disturbed sites. The high daily fish sale income ranging from US$ 8 to 12 and the high‐percentage (52%) catch preference of all large wetland fish species were observed for the less‐disturbed sites. A high percentage of respondents from the area of the less‐disturbed sites had higher annual incomes, resulting in more accumulated wealth than for the highly disturbed Nsango site, whose fishery was affected by large‐scale rice schemes. The overall socio‐economic impact of the small‐scale fishery, based on the data regarding the number of fishermen and their dependents, and the income from fish sales and other wetland activities, was low, with differences between sites being attributed to the level of wetland disturbance. The Mpologoma wetland is threatened by overexploitation of its fisheries services, but also overlooked and undervalued by policymakers because of inadequate fisheries statistics. Thus, the information derived from this study will facilitate the formulation and design of riverine wetland‐specific and small‐scale fisheries management strategies.
显示更多 [+] 显示较少 [-]Implications of catch composition from a small-scale swimming crab fishery for gear selectivity | นัยยะของผลผลิตประมงปูม้าจากแหล่งประมงพื้นบ้านต่อการเลือกจับของเครื่องมือประมงปูม้า 全文
2014
Jiraporn Trisak(Kasetsart University, Bangkok (Thailand). Faculty of Fisheries. Department of Fisheries Management) E-mail:jiraporn.t@ku.ac.th | Jakrapanth Punpruksanan(Kasetsart University, Bangkok (Thailand). Faculty of Fisheries. Department of Fisheries Management)
Is community-based fisheries management realising multiple objectives? Examining evidence from the literature 全文
2014
Cohen, P.J. | Jupiter, S.D. | Weeks, R. | Tawake, A. | Govan, H.
Community-based and co-management approaches are key strategies for small-scale fisheries management. The expansion of these approaches is particularly apparent in the Pacific, where communities rely heavily on small-scale fisheries and concerns about sustainability are increasing. Many community-based management initiatives are recognised within a regional practitioner's network referred to as the Locally Managed Marine Area (LMMA) network. This paper discuss how LMMAs may achieve the following objectives: 1) increasing short-term harvesting efficiency; 2) restoring biodiversity and ecosystems; 3) maintaining or restoring breeding biomass; 4) enhancing livelihoods; 5) reinforcing customs; 6) asserting access rights; and 7) community empowerment.
显示更多 [+] 显示较少 [-]Biomass management targets and the conservation and economic benefits of marine reserves 全文
2014
Yamazaki, Satoshi | Grafton, Quentin R | Kompas, Tom | Jennings, Sarah
The establishment of no‐take marine reserves has been increasingly promoted as a key measure to achieve conservation and sustainability goals in fisheries. Regardless of the wide range of benefits cited, the effectiveness of reserve establishment depends critically on fisheries management outside the reserves. We construct a bioeconomic model of a fishery that allows for the establishment of a no‐take marine reserve and evaluate how the choice of the off‐reserve management target influences the effectiveness of reserve establishment. We evaluate two biomass targets: (i) BMSY or the biomass that produces the maximum sustainable yield (MSY) and (ii) BMEY or the biomass that maximizes the net present value of the returns to fishing. The parameterized model shows that, for a wide range of scenarios, the fishery will be better off in terms of both conservation and economic objectives when the no‐take reserve is established in conjunction with the BMEY target rather than with the BMSY target. Model results further show that the opportunity cost of securing additional fish biomass, in both deterministic and stochastic environments, is lower when the reserve size is increased under the BMEY target. This finding is important because marine reserves have been established as a key measure to restore depleted fish stocks, and the results suggest that this objective can be achieved with lower economic costs in a BMEY managed fishery.
显示更多 [+] 显示较少 [-]Performance of regional fisheries management organizations: ecosystem‐based governance of bycatch and discards 全文
2014
Gilman, Eric | Passfield, Kelvin | Nakamura, Katrina
A performance assessment was conducted of regional fisheries management organizations’ (RFMOs’) bycatch governance, one element of an ecosystem approach to fisheries management. Obtaining a mean score of 25%, with a 64% CV, collectively the RFMOs have large governance deficits. Individually, there has been mixed progress, with some RFMOs having made substantial progress for some governance elements. There has been nominal progress in gradually transitioning to ecosystem‐based fisheries management: controls largely do not account for broad or multispecies effects of fishing, and cross‐sectoral marine spatial planning is limited. Regional observers collect half of minimum information needed to assess the efficacy of bycatch measures. Over two‐thirds of RFMO‐managed fisheries lack regional observer coverage. International exchange of observers occurs in one‐third of programmes. There is no open access to research‐grade regional observer data. Ecological risk assessments focus on effects of bycatch removals on vulnerable species groups and effects of fishing on vulnerable benthic marine ecosystems. RFMOs largely do not assess or manage cryptic, generally undetectable sources of fishing mortality. Binding measures address about one‐third of bycatch problems. Eighty per cent of measures lack explicit performance standards against which to assess efficacy. Measures are piecemeal, developed without considering potential conflicts across vulnerable groups. RFMOs employ 60% of surveillance methods required to assess compliance. A lack of transparency and limited reporting of inspection effort, identified infractions, enforcement actions and outcomes further limits the ability to assess compliance. Augmented harmonization could help to fill identified deficits.
显示更多 [+] 显示较少 [-]The Effects of Spatial and Temporal Resolution in Simulating Fish Movement in Individual-Based Models 全文
2014
Watkins, Katherine Shepard | Rose, Kenneth A.
Many fisheries management decisions require predictions of spatial dynamics, and simulation of realistic movement is critically important for accurately representing population-level dynamics with spatially explicit individual-based models (IBMs). Movement approaches developed to date have been applied across a wide range of spatiotemporal resolutions. We compared four movement approaches or submodels (restricted-area search, kinesis, event based, and run and tumble) using an IBM (roughly based on Bay Anchovy Anchoa mitchilli and Northern Anchovy Engraulis mordax) that simulated growth, mortality, and movement of a cohort on a two-dimensional grid. We evaluated the submodels in 2.7- × 2.7-km environments at five resolutions defined by various cell sizes and time steps. We used a genetic algorithm to calibrate each movement submodel over a 300-generation training phase and then tested the mean movement parameters for a single generation in the training environment and a novel environment. Restricted-area search, kinesis, and event-based submodels had higher egg production than a random walk model (baseline, assuming no behavioral movement) across spatiotemporal resolutions in training and novel environments. The run-and-tumble submodel also had higher egg production than the random walk model but only under certain conditions. Although restricted-area, kinesis, and event-based submodels outperformed random walk at all resolutions, the submodels did not perform equally well across resolutions in terms of egg production and aggregation of model individuals in high-quality cells (i.e., those with high growth and low mortality). The variability in performance was due to the change in habitat quality experienced by model individuals from one time step to the next. Restricted-area and event-based submodels had higher egg production when model individuals experienced small changes in habitat quality, whereas the kinesis and run-and-tumble submodels performed better when model individuals experienced larger changes in habitat quality.
显示更多 [+] 显示较少 [-]Is community-based fisheries management realising multiple objectives? Examining evidence from the literature 全文
2014
Cohen, P.J. | Jupiter, S.D. | Weeks, R. | Tawake, A. | Govan, H.
Community-based and co-management approaches are key strategies for small-scale fisheries management. The expansion of these approaches is particularly apparent in the Pacific, where communities rely heavily on small-scale fisheries and concerns about sustainability are increasing. Many community-based management initiatives are recognised within a regional practitioner’s network referred to as the Locally Managed Marine Area (LMMA) network. This paper discuss how LMMAs may achieve the following objectives: 1) increasing short-term harvesting efficiency; 2) restoring biodiversity and ecosystems; 3) maintaining or restoring breeding biomass; 4) enhancing livelihoods; 5) reinforcing customs; 6) asserting access rights; and 7) community empowerment.
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