The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
T K Kar - One of the best experts on this subject based on the ideXlab platform.
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impacts of predator prey interaction on managing Maximum Sustainable Yield and resilience
Nonlinear Analysis-Modelling and Control, 2020Co-Authors: Kanisha Pujaru, T K KarAbstract:This paper gives a broad outline of some comparative analysis of two ecological services, namely, Yield and resilience of a generalist predator–prey system. Although either prey or predator species can be harvested at Maximum Sustainable Yield (MSY) level, yet there is a trade-off between Yield and resilience. When both the species are harvested simultaneously, MSY increase by changing catchabilities always increases the system resilience both in prey- and predator-oriented fishery. In particular, a prey-oriented fishery with low prey catchability gives more Yield and resilience but in case of predator-oriented fishery with high predator catchability, gives more of these ecological services. Thus to get both the optimum Yield and resilience, a balanced harvesting approach is needed between the prey and predator trophic levels. Throughout the analysis, we use both the analytical as well as numerical techniques.
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balancing Maximum Sustainable Yield and ecological resilience in an exploited two predator one prey system
BioSystems, 2020Co-Authors: T K Kar, Debprasad Pal, Atsushi Yamauchi, Bapan GhoshAbstract:In this paper, we consider a two-predator one-prey system to determine the feedback of exploitation in individual as well as joint population levels. As balancing Yield with resilience is highly essential for the conservation of species in the marine ecosystem, here we measure both the Maximum Sustainable Yield (MSY) and resilience simultaneously. Then we investigate both the trade-offs and synergies among Maximum Yield, conservation, and resilience that emerge from different harvesting plans. It is found that for single species harvesting, a prey species-oriented system is capable of producing more Yield in compare to any predator-oriented system but for resilience, a prey species-oriented system is far behind the others. In the case of joint harvesting of all the species, it is observed that the first predator-oriented system has a better ability to absorb the disturbances than the other cases. The correlation between Yield and resilience at the MSY level is studied in all the cases. It is further observed that the increase of intraspecific competition in the predator decreases the risk of sustainability. In this way, this study may be helpful for fishery management to fulfill their goals without affecting the ecosystem's health in the long run.
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impact of marine reserve on Maximum Sustainable Yield in a traditional prey predator system
Communications in Nonlinear Science and Numerical Simulation, 2018Co-Authors: Prosenjit Paul, T K Kar, Abhijit GhoraiAbstract:Abstract Multispecies fisheries management requires managers to consider the impact of fishing activities on several species as fishing impacts both targeted and non-targeted species directly or indirectly in several ways. The intended goal of traditional fisheries management is to achieve Maximum Sustainable Yield (MSY) from the targeted species, which on many occasions affect the targeted species as well as the entire ecosystem. Marine reserves are often acclaimed as the marine ecosystem management tool. Few attempts have been made to generalize the ecological effects of marine reserve on MSY policy. We examine here how MSY and population level in a prey-predator system are affected by the low, medium and high reserve size under different possible scenarios. Our simulation works shows that low reserve area, the value of MSY for prey exploitation is Maximum when both prey and predator species have fast movement rate. For medium reserve size, our analysis revealed that the Maximum value of MSY for prey exploitation is obtained when prey population has fast movement rate and predator population has slow movement rate. For high reserve area, the Maximum value of MSY for prey’s exploitation is very low compared to the Maximum value of MSY for prey’s exploitation in case of low and medium reserve. On the other hand, for low and medium reserve area, MSY for predator exploitation is Maximum when both the species have fast movement rate.
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possible ecosystem impacts of applying Maximum Sustainable Yield policy in food chain models
Journal of Theoretical Biology, 2013Co-Authors: Bapan Ghosh, T K KarAbstract:This paper describes the possible impacts of Maximum Sustainable Yield (MSY) and Maximum Sustainable total Yield (MSTY) policy in ecosystems. In general it is observed that exploitation at MSY (of single species) or MSTY (of multispecies) level may cause the extinction of several species. In particular, for traditional prey–predator system, fishing under combined harvesting effort at MSTY (if it exists) level may be a Sustainable policy, but if MSTY does not exist then it is due to the extinction of the predator species only. In generalist prey–predator system, harvesting of any one of the species at MSY level is always a Sustainable policy, but harvesting of both the species at MSTY level may or may not be a Sustainable policy. In addition, we have also investigated the MSY and MSTY policy in a traditional tri-trophic and four trophic food chain models.
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Maximum Sustainable Yield and species extinction in a prey predator system some new results
Journal of Biological Physics, 2013Co-Authors: Bapan Ghosh, T K KarAbstract:Though the Maximum Sustainable Yield (MSY) approach has been legally adopted for the management of world fisheries, it does not provide any guarantee against from species extinction in multispecies communities. In the present article, we describe the appropriateness of the MSY policy in a Holling–Tanner prey–predator system with different types of functional responses. It is observed that for both type I and type II functional responses, harvesting of either prey or predator species at the MSY level is a Sustainable fishing policy. In the case of combined harvesting, both the species coexist at the Maximum Sustainable total Yield (MSTY) level if the biotic potential of the prey species is greater than a threshold value. Further, increase of the biotic potential beyond the threshold value affects the persistence of the system.
Bapan Ghosh - One of the best experts on this subject based on the ideXlab platform.
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balancing Maximum Sustainable Yield and ecological resilience in an exploited two predator one prey system
BioSystems, 2020Co-Authors: T K Kar, Debprasad Pal, Atsushi Yamauchi, Bapan GhoshAbstract:In this paper, we consider a two-predator one-prey system to determine the feedback of exploitation in individual as well as joint population levels. As balancing Yield with resilience is highly essential for the conservation of species in the marine ecosystem, here we measure both the Maximum Sustainable Yield (MSY) and resilience simultaneously. Then we investigate both the trade-offs and synergies among Maximum Yield, conservation, and resilience that emerge from different harvesting plans. It is found that for single species harvesting, a prey species-oriented system is capable of producing more Yield in compare to any predator-oriented system but for resilience, a prey species-oriented system is far behind the others. In the case of joint harvesting of all the species, it is observed that the first predator-oriented system has a better ability to absorb the disturbances than the other cases. The correlation between Yield and resilience at the MSY level is studied in all the cases. It is further observed that the increase of intraspecific competition in the predator decreases the risk of sustainability. In this way, this study may be helpful for fishery management to fulfill their goals without affecting the ecosystem's health in the long run.
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possible ecosystem impacts of applying Maximum Sustainable Yield policy in food chain models
Journal of Theoretical Biology, 2013Co-Authors: Bapan Ghosh, T K KarAbstract:This paper describes the possible impacts of Maximum Sustainable Yield (MSY) and Maximum Sustainable total Yield (MSTY) policy in ecosystems. In general it is observed that exploitation at MSY (of single species) or MSTY (of multispecies) level may cause the extinction of several species. In particular, for traditional prey–predator system, fishing under combined harvesting effort at MSTY (if it exists) level may be a Sustainable policy, but if MSTY does not exist then it is due to the extinction of the predator species only. In generalist prey–predator system, harvesting of any one of the species at MSY level is always a Sustainable policy, but harvesting of both the species at MSTY level may or may not be a Sustainable policy. In addition, we have also investigated the MSY and MSTY policy in a traditional tri-trophic and four trophic food chain models.
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Maximum Sustainable Yield and species extinction in a prey predator system some new results
Journal of Biological Physics, 2013Co-Authors: Bapan Ghosh, T K KarAbstract:Though the Maximum Sustainable Yield (MSY) approach has been legally adopted for the management of world fisheries, it does not provide any guarantee against from species extinction in multispecies communities. In the present article, we describe the appropriateness of the MSY policy in a Holling–Tanner prey–predator system with different types of functional responses. It is observed that for both type I and type II functional responses, harvesting of either prey or predator species at the MSY level is a Sustainable fishing policy. In the case of combined harvesting, both the species coexist at the Maximum Sustainable total Yield (MSTY) level if the biotic potential of the prey species is greater than a threshold value. Further, increase of the biotic potential beyond the threshold value affects the persistence of the system.
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impacts of Maximum Sustainable Yield policy to prey predator systems
Ecological Modelling, 2013Co-Authors: T K Kar, Bapan GhoshAbstract:Abstract This article investigates the effects of reaching the Maximum Sustainable Yield ( MSY ) in prey–predator systems where the prey population follows logistic law of growth. Two different models are proposed: (i) first model involves linear prey–predator interaction and intraspecific competition among predator populations, and (ii) the second one is a ratio-dependent prey–predator system. In the first model, our results suggest that the introduction of intraspecific competition among predator population has important consequences for the fishing to reach MSY from prey species and Maximum Sustainable total Yield (MSTY) for combined harvesting of both prey and predator species. On the otherhand, in the second model, our results suggest that though the harvesting of prey species at MSY level shall be guaranteed the coexistence of both the species, but the combined harvesting of both the species at MSTY level may cause extinction of the predator species. However, for both the models, predator harvesting at MSY level may be a Sustainable fishing policy. Therefore, based on our results we can conclude that MSY (or MSTY) policy in prey–predator systems in nature are not likely to fit requirements of Conservation of Biological Diversity ( CBD, 1992 ) in all cases.
George Leitmann - One of the best experts on this subject based on the ideXlab platform.
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on the attainment of the Maximum Sustainable Yield in the verhulst lotka volterra model
Automatica, 2019Co-Authors: Luca Lambertini, George LeitmannAbstract:Abstract We reformulate the Verhulst–Lotka–Volterra model of natural resource extraction under the alternative assumptions of Cournot behaviour and perfect competition, to revisit the tragedy of commons vs the possibility of Sustainable harvesting. After a brief layout of the open-loop solution including the Ramsey rule, we rely on the state-redundancy property and the consequent strong time consistency of the static equilibrium output to investigate the different impact of demand elasticity on the regulator’s possibility of driving industry harvest to the Maximum Sustainable Yield in the two settings. The presence of a flat demand function offers the authority a fully effective regulatory tool in the form of the exogenous price faced by perfectly competitive firms, to drive their collective harvest rate to the Maximum Sustainable Yield. The same cannot happen under Cournot competition, as in this case the price is endogenous and the regulator’s policy is confined to limiting access to the common pool.
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on the attainment of the Maximum Sustainable Yield in the verhulst lotka volterra model
Social Science Research Network, 2017Co-Authors: Luca Lambertini, George LeitmannAbstract:We reformulate the Verhulst-Lotka-Volterra model of natural resource extraction under the alternative assumptions of Cournot behaviour and perfect competition, to revisit the tragedy of commons vs the possibility of Sustainable harvesting. We stress the different impact of demand elasticity on the regulator’s possibility of driving industry harvest to the Maximum Sustainable Yield in the two settings. The presence of a flat demand function offers the authority a fully effective regulatory tool in the form of the exogeneous price faced by perfectly competitive firms, to drive their collective harvest rate at the Maximum Sustainable Yield. The same cannot happen under Cournot competition, as in this case the price is endogenous and the regulator’s policy is confined to limiting access to the common pool.
Anna Rindorf - One of the best experts on this subject based on the ideXlab platform.
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Achieving Maximum Sustainable Yield in mixed fisheries: a management approach for the North Sea demersal fisheries
ICES Journal of Marine Science, 2016Co-Authors: Clara Ulrich, Youen Vermard, Paul J. Dolder, Thomas Brunel, Ernesto Jardim, Steven J. Holmes, Alexander Kempf, Lars O. Mortensen, Jan Jaap Poos, Anna RindorfAbstract:Achieving single species Maximum Sustainable Yield (MSY) in complex and dynamic fisheries targeting multiple species (mixed fisheries) is challenging because achieving the objective for one species may mean missing the objective for another. The North Sea mixed fisheries are a representative example of an issue that is generic across most demersal fisheries worldwide, with the diversity of species and fisheries inducing numerous biological and technical interactions. Building on a rich knowledge base for the understanding and quantification of these interactions, new approaches have emerged. Recent paths towards operationalizing MSY at the regional scale have suggested the expansion of the concept into a desirable area of “pretty good Yield”, implemented through a range around FMSY that would allow for more flexibility in management targets. This article investigates the potential of FMSY ranges to combine long-term single-stock targets with flexible, short-term, mixed-fisheries management requirements applied to the main North Sea demersal stocks. It is shown that sustained fishing at the upper bound of the range may lead to unacceptable risks when technical interactions occur. An objective method is suggested that provides an optimal set of fishing mortality within the range, minimizing the risk of total allowable catch mismatches among stocks captured within mixed fisheries, and addressing explicitly the trade-offs between the most and least productive stocks.
Axel G Rossberg - One of the best experts on this subject based on the ideXlab platform.
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Maximum Sustainable Yield from interacting fish stocks in an uncertain world two policy choices and underlying trade offs
Ices Journal of Marine Science, 2016Co-Authors: Adrian Farcas, Axel G RossbergAbstract:The case of sheries management illustrates how the inherent structural instability of ecosystems can have deep-running policy implications. We contrast eleven types of management plans to achieve Maximum Sustainable Yields (MSY) from multiple stocks and compare their eectiveness based on the results of management strategy evaluations (MSE) that use complex food webs in their operating models. Plans that primarily target specic stock sizes ( BMSY) consistently led to higher Yields than plans targeting specic shing pressures ( FMSY). A new type of selfoptimising control rule, introduced here to conquer uncertainty due to structural instability, led to intermediate Yields. Plans to \maximise the Yield from each stock separately" in the sense of a Nash equilibrium produced total Yields comparable to Yields from plans to maximise total harvested biomass, but tended to be more robust to structural instability. Most types of plans outperformed single-species management plans that set pressure targets without explicitly considering ecological interactions. Our analyses highlight trade-os between Yields, amiability to fair negotiations, and continuity with current approaches in the European context. Based on these results, we recommend directions for future developments of EU sheries policy.
