The Experts below are selected from a list of 54315 Experts worldwide ranked by ideXlab platform
Zhibin Zhang - One of the best experts on this subject based on the ideXlab platform.
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Simulation of lethal Control and Fertility Control in a demographic model for Brandt’s vole Microtus brandti
Journal of Applied Ecology, 2002Co-Authors: Dazhao Shi, Stephen Davis, Roger P Pech, Xinrong Wan, Zhibin ZhangAbstract:Summary 1 Brandt’s vole Microtus brandti is considered a pest in China and is actively managed through the use of toxic baits. A time-dependent density-dependent Leslie matrix model was developed to investigate the effectiveness of Fertility Control as an alternative. 2 Three annual cycles of Brandt’s vole were observed between 1995 and 1998 at a site in the grasslands of Inner Mongolia, China. For each of these cycles, cohort-specific monthly survival rates were derived for the spring, summer and autumn months. Over the breeding season, monthly reproductive rates were obtained as numbers of young females per adult female. 3 Survival of voles over winter, a 5–6-month period, depended on age at the onset of winter and the density in autumn. 4 The model was parameterized with measured and continuously varying monthly data for vital rates. It was then used to predict the impact that Fertility Control, delivered with non-toxic baits, and lethal Control would have had on the vole population if Control had been imposed in the autumn of 1994 or spring of 1995. The timing and frequency of bait delivery were varied, and we considered the population response to bait that renders females sterile and bait that renders females only temporarily infertile. 5 The model suggested that the effectiveness of lethal Control in spring could be matched by Fertility Control if it was applied twice in the spring of a year in which high densities were reached, or in the previous autumn. The latter requires that (i) inFertility is long-lasting in treated animals and (ii) either high-density years be reliably forecast a year ahead or Fertility Control be applied every autumn. 6 Brandt’s voles provide an exception to the general rule that Fertility Control is never more effective than lethal Control applied at the same time with the same bait uptake. We found that when Control was applied in autumn, Fertility Control was better than lethal Control in reducing the numbers of voles over the following spring, summer and autumn. This is because normal density-dependent mortality over winter has a greater impact following Fertility Control than lethal Control.
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simulation of lethal Control and Fertility Control in a demographic model for brandt s vole microtus brandti
Journal of Applied Ecology, 2002Co-Authors: Stephen Davis, Roger P Pech, Zhibin ZhangAbstract:Summary 1 Brandt’s vole Microtus brandti is considered a pest in China and is actively managed through the use of toxic baits. A time-dependent density-dependent Leslie matrix model was developed to investigate the effectiveness of Fertility Control as an alternative. 2 Three annual cycles of Brandt’s vole were observed between 1995 and 1998 at a site in the grasslands of Inner Mongolia, China. For each of these cycles, cohort-specific monthly survival rates were derived for the spring, summer and autumn months. Over the breeding season, monthly reproductive rates were obtained as numbers of young females per adult female. 3 Survival of voles over winter, a 5–6-month period, depended on age at the onset of winter and the density in autumn. 4 The model was parameterized with measured and continuously varying monthly data for vital rates. It was then used to predict the impact that Fertility Control, delivered with non-toxic baits, and lethal Control would have had on the vole population if Control had been imposed in the autumn of 1994 or spring of 1995. The timing and frequency of bait delivery were varied, and we considered the population response to bait that renders females sterile and bait that renders females only temporarily infertile. 5 The model suggested that the effectiveness of lethal Control in spring could be matched by Fertility Control if it was applied twice in the spring of a year in which high densities were reached, or in the previous autumn. The latter requires that (i) inFertility is long-lasting in treated animals and (ii) either high-density years be reliably forecast a year ahead or Fertility Control be applied every autumn. 6 Brandt’s voles provide an exception to the general rule that Fertility Control is never more effective than lethal Control applied at the same time with the same bait uptake. We found that when Control was applied in autumn, Fertility Control was better than lethal Control in reducing the numbers of voles over the following spring, summer and autumn. This is because normal density-dependent mortality over winter has a greater impact following Fertility Control than lethal Control.
Thompson N Hobbs - One of the best experts on this subject based on the ideXlab platform.
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forecasting the effects of Fertility Control on overabundant ungulates white tailed deer in the national capital region
PLOS ONE, 2015Co-Authors: Ann Raiho, Mevin B Hooten, Scott T Bates, Thompson N HobbsAbstract:Overabundant populations of ungulates have caused environmental degradation and loss of biological diversity in ecosystems throughout the world. Culling or regulated harvest is often used to Control overabundant species. These methods are difficult to implement in national parks, other types of conservation reserves, or in residential areas where public hunting may be forbidden by policy. As a result, Fertility Control has been recommended as a non-lethal alternative for regulating ungulate populations. We evaluate this alternative using white-tailed deer in national parks in the vicinity of Washington, D.C., USA as a model system. Managers seek to reduce densities of white-tailed deer from the current average (50 deer per km2) to decrease harm to native plant communities caused by deer. We present a Bayesian hierarchical model using 13 years of population estimates from 8 national parks in the National Capital Region Network. We offer a novel way to evaluate management actions relative to goals using short term forecasts. Our approach confirms past analyses that Fertility Control is incapable of rapidly reducing deer abundance. Fertility Control can be combined with culling to maintain a population below carrying capacity with a high probability of success. This gives managers confronted with problematic overabundance a framework for implementing management actions with a realistic assessment of uncertainty.
Stephen Davis - One of the best experts on this subject based on the ideXlab platform.
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Simulation of lethal Control and Fertility Control in a demographic model for Brandt’s vole Microtus brandti
Journal of Applied Ecology, 2002Co-Authors: Dazhao Shi, Stephen Davis, Roger P Pech, Xinrong Wan, Zhibin ZhangAbstract:Summary 1 Brandt’s vole Microtus brandti is considered a pest in China and is actively managed through the use of toxic baits. A time-dependent density-dependent Leslie matrix model was developed to investigate the effectiveness of Fertility Control as an alternative. 2 Three annual cycles of Brandt’s vole were observed between 1995 and 1998 at a site in the grasslands of Inner Mongolia, China. For each of these cycles, cohort-specific monthly survival rates were derived for the spring, summer and autumn months. Over the breeding season, monthly reproductive rates were obtained as numbers of young females per adult female. 3 Survival of voles over winter, a 5–6-month period, depended on age at the onset of winter and the density in autumn. 4 The model was parameterized with measured and continuously varying monthly data for vital rates. It was then used to predict the impact that Fertility Control, delivered with non-toxic baits, and lethal Control would have had on the vole population if Control had been imposed in the autumn of 1994 or spring of 1995. The timing and frequency of bait delivery were varied, and we considered the population response to bait that renders females sterile and bait that renders females only temporarily infertile. 5 The model suggested that the effectiveness of lethal Control in spring could be matched by Fertility Control if it was applied twice in the spring of a year in which high densities were reached, or in the previous autumn. The latter requires that (i) inFertility is long-lasting in treated animals and (ii) either high-density years be reliably forecast a year ahead or Fertility Control be applied every autumn. 6 Brandt’s voles provide an exception to the general rule that Fertility Control is never more effective than lethal Control applied at the same time with the same bait uptake. We found that when Control was applied in autumn, Fertility Control was better than lethal Control in reducing the numbers of voles over the following spring, summer and autumn. This is because normal density-dependent mortality over winter has a greater impact following Fertility Control than lethal Control.
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simulation of lethal Control and Fertility Control in a demographic model for brandt s vole microtus brandti
Journal of Applied Ecology, 2002Co-Authors: Stephen Davis, Roger P Pech, Zhibin ZhangAbstract:Summary 1 Brandt’s vole Microtus brandti is considered a pest in China and is actively managed through the use of toxic baits. A time-dependent density-dependent Leslie matrix model was developed to investigate the effectiveness of Fertility Control as an alternative. 2 Three annual cycles of Brandt’s vole were observed between 1995 and 1998 at a site in the grasslands of Inner Mongolia, China. For each of these cycles, cohort-specific monthly survival rates were derived for the spring, summer and autumn months. Over the breeding season, monthly reproductive rates were obtained as numbers of young females per adult female. 3 Survival of voles over winter, a 5–6-month period, depended on age at the onset of winter and the density in autumn. 4 The model was parameterized with measured and continuously varying monthly data for vital rates. It was then used to predict the impact that Fertility Control, delivered with non-toxic baits, and lethal Control would have had on the vole population if Control had been imposed in the autumn of 1994 or spring of 1995. The timing and frequency of bait delivery were varied, and we considered the population response to bait that renders females sterile and bait that renders females only temporarily infertile. 5 The model suggested that the effectiveness of lethal Control in spring could be matched by Fertility Control if it was applied twice in the spring of a year in which high densities were reached, or in the previous autumn. The latter requires that (i) inFertility is long-lasting in treated animals and (ii) either high-density years be reliably forecast a year ahead or Fertility Control be applied every autumn. 6 Brandt’s voles provide an exception to the general rule that Fertility Control is never more effective than lethal Control applied at the same time with the same bait uptake. We found that when Control was applied in autumn, Fertility Control was better than lethal Control in reducing the numbers of voles over the following spring, summer and autumn. This is because normal density-dependent mortality over winter has a greater impact following Fertility Control than lethal Control.
Roger P Pech - One of the best experts on this subject based on the ideXlab platform.
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Simulation of lethal Control and Fertility Control in a demographic model for Brandt’s vole Microtus brandti
Journal of Applied Ecology, 2002Co-Authors: Dazhao Shi, Stephen Davis, Roger P Pech, Xinrong Wan, Zhibin ZhangAbstract:Summary 1 Brandt’s vole Microtus brandti is considered a pest in China and is actively managed through the use of toxic baits. A time-dependent density-dependent Leslie matrix model was developed to investigate the effectiveness of Fertility Control as an alternative. 2 Three annual cycles of Brandt’s vole were observed between 1995 and 1998 at a site in the grasslands of Inner Mongolia, China. For each of these cycles, cohort-specific monthly survival rates were derived for the spring, summer and autumn months. Over the breeding season, monthly reproductive rates were obtained as numbers of young females per adult female. 3 Survival of voles over winter, a 5–6-month period, depended on age at the onset of winter and the density in autumn. 4 The model was parameterized with measured and continuously varying monthly data for vital rates. It was then used to predict the impact that Fertility Control, delivered with non-toxic baits, and lethal Control would have had on the vole population if Control had been imposed in the autumn of 1994 or spring of 1995. The timing and frequency of bait delivery were varied, and we considered the population response to bait that renders females sterile and bait that renders females only temporarily infertile. 5 The model suggested that the effectiveness of lethal Control in spring could be matched by Fertility Control if it was applied twice in the spring of a year in which high densities were reached, or in the previous autumn. The latter requires that (i) inFertility is long-lasting in treated animals and (ii) either high-density years be reliably forecast a year ahead or Fertility Control be applied every autumn. 6 Brandt’s voles provide an exception to the general rule that Fertility Control is never more effective than lethal Control applied at the same time with the same bait uptake. We found that when Control was applied in autumn, Fertility Control was better than lethal Control in reducing the numbers of voles over the following spring, summer and autumn. This is because normal density-dependent mortality over winter has a greater impact following Fertility Control than lethal Control.
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simulation of lethal Control and Fertility Control in a demographic model for brandt s vole microtus brandti
Journal of Applied Ecology, 2002Co-Authors: Stephen Davis, Roger P Pech, Zhibin ZhangAbstract:Summary 1 Brandt’s vole Microtus brandti is considered a pest in China and is actively managed through the use of toxic baits. A time-dependent density-dependent Leslie matrix model was developed to investigate the effectiveness of Fertility Control as an alternative. 2 Three annual cycles of Brandt’s vole were observed between 1995 and 1998 at a site in the grasslands of Inner Mongolia, China. For each of these cycles, cohort-specific monthly survival rates were derived for the spring, summer and autumn months. Over the breeding season, monthly reproductive rates were obtained as numbers of young females per adult female. 3 Survival of voles over winter, a 5–6-month period, depended on age at the onset of winter and the density in autumn. 4 The model was parameterized with measured and continuously varying monthly data for vital rates. It was then used to predict the impact that Fertility Control, delivered with non-toxic baits, and lethal Control would have had on the vole population if Control had been imposed in the autumn of 1994 or spring of 1995. The timing and frequency of bait delivery were varied, and we considered the population response to bait that renders females sterile and bait that renders females only temporarily infertile. 5 The model suggested that the effectiveness of lethal Control in spring could be matched by Fertility Control if it was applied twice in the spring of a year in which high densities were reached, or in the previous autumn. The latter requires that (i) inFertility is long-lasting in treated animals and (ii) either high-density years be reliably forecast a year ahead or Fertility Control be applied every autumn. 6 Brandt’s voles provide an exception to the general rule that Fertility Control is never more effective than lethal Control applied at the same time with the same bait uptake. We found that when Control was applied in autumn, Fertility Control was better than lethal Control in reducing the numbers of voles over the following spring, summer and autumn. This is because normal density-dependent mortality over winter has a greater impact following Fertility Control than lethal Control.
Ann Raiho - One of the best experts on this subject based on the ideXlab platform.
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forecasting the effects of Fertility Control on overabundant ungulates white tailed deer in the national capital region
PLOS ONE, 2015Co-Authors: Ann Raiho, Mevin B Hooten, Scott T Bates, Thompson N HobbsAbstract:Overabundant populations of ungulates have caused environmental degradation and loss of biological diversity in ecosystems throughout the world. Culling or regulated harvest is often used to Control overabundant species. These methods are difficult to implement in national parks, other types of conservation reserves, or in residential areas where public hunting may be forbidden by policy. As a result, Fertility Control has been recommended as a non-lethal alternative for regulating ungulate populations. We evaluate this alternative using white-tailed deer in national parks in the vicinity of Washington, D.C., USA as a model system. Managers seek to reduce densities of white-tailed deer from the current average (50 deer per km2) to decrease harm to native plant communities caused by deer. We present a Bayesian hierarchical model using 13 years of population estimates from 8 national parks in the National Capital Region Network. We offer a novel way to evaluate management actions relative to goals using short term forecasts. Our approach confirms past analyses that Fertility Control is incapable of rapidly reducing deer abundance. Fertility Control can be combined with culling to maintain a population below carrying capacity with a high probability of success. This gives managers confronted with problematic overabundance a framework for implementing management actions with a realistic assessment of uncertainty.