The purpose of this paper is to explore the promise of utilizing some relatively new feedback control techniques in ecosystem management. First, we set forth a basic ecological-economic model of a predator-prey-huntin...The purpose of this paper is to explore the promise of utilizing some relatively new feedback control techniques in ecosystem management. First, we set forth a basic ecological-economic model of a predator-prey-hunting system in which both the predator and prey have use(flow) and non-use(stock) value and when the predator can inflict transboundary damages. We then use new data from the US Mountain West to show how a particular feedback approach—linear parameter-varying(LPV) control—can be utilized in this context. Our LPV model is able to quantify the cost of managing disturbances that inevitably arise as a manager tries to keep the actual path of the system "close" to its optimum. The results suggest management strategies in mountain ecosystems that feature large, mammalian carnivores.展开更多
After being kept in captivity and isolated from natural predators for more than 1,200 years, P6re David's deer has been reintroduced in China and now occurs in a reserve where human activity is the only potential thr...After being kept in captivity and isolated from natural predators for more than 1,200 years, P6re David's deer has been reintroduced in China and now occurs in a reserve where human activity is the only potential threat. Antipredator vigilance i~ an important component of survival for many prey animals in their natural habitat. Do deer still adjust vigilance as a function of risk after such a long period of relaxed predation pressure? Here, we examined vigilance levels in P6re David's deer groups as a function of group size, sex and level of human disturbance. The results showed that individual vigilance significantly decreased with group size in all-female groups but not in all-males or mixed-sex groups. In rutting season, males compete with one another and harass females, and we argue that vigilance is partly aimed at threatening males and that such vigilance increases with group size. This explains why overall vigilance did not vary with group size for males in general and for females in mixed-sex groups. Vigilance increased in more disturbed areas but in in male deer only. The results indicate that despite relaxed predation pressure over centuries, P6re David's deer can still adjust antipredator responses as a function of perceived risk. Such information may become useful in the rewilding programme now under way for this species in China [Current Zoology 59 (2): 265-270, 2013].展开更多
The reintroduction of rare and endangered species is one of the most important approaches to conservation and ecosystem restoration,but it has still proven to be an adventurous undertaking and most reintroduction prog...The reintroduction of rare and endangered species is one of the most important approaches to conservation and ecosystem restoration,but it has still proven to be an adventurous undertaking and most reintroduction programmes fail,so successful demonstrations are needed.Père David’s deer(Elaphurus davidianus,Milu in Chinese)could be considered one of conservation’s great success stories,as this species’path on the road to extinction has been reversed by a combination of ex-situ conservation and successful re-introduction in China.The species had been consigned to an imperial hunting ground when the last Chinese herds were exterminated during the fall of the Qing Dynasty(1644-1912).Fortunately,a few of the last remaining individuals were sent to European zoos.From these animals,a herd was bred on the 14;Duke of Bedford’s estate,Woburn Abbey,and between 1985and 1987,and 38 Milu were donated back to China for re-introduction in Beijing Milu Park(BMP),the former imperial hunting ground.An additional 39 deer were released at Dafeng National Nature Reserve(DFNNR),Jiangsu Province in 1986.In both of these safe and protected locations,the Milu thrived allowing for over 700 Milu to be sent to a further 82 sites throughout the species’original Chinese range over the last 36 years.As a result,the Milu population totaled 9136 by 2021,with 2855 individuals now living back in the wild;while another 5681 individuals inhabit the DFNNR,and 186 reside in BMP.Wild Milu,however,still face significant conservation challenges.The population lacks genetic diversity,leading to severe inbreeding depression and carrying multiple risks,such as high miscarriage rates,a reduced lifespan,and susceptibility to disease.Environmental constraints such as pollution and habitat fragmentation further result in small,fragmented wild populations.Moreover,the species currently lacks a national level conservation master plan,the associated coordinated monitoring platforms,and breeding plans for China’s captive populations.Finally,there is now a lack of international cooperation in the conservation of this species.We therefore call for both a national-level conservation master plan in China and international cooperation to develop a shared database and germplasm databank covering Milu across all countries with ex-situ populations,as crucial steps for securing the long-term conservation of Milu and preventing it from ever becoming“extinct in the wild”again.展开更多
Considering the severe impacts of genetic bottlenecks and small numbers of founders in populations of reintroduced animals, it is necessary to study inbreeding and its effect on fitness in species of conservation conc...Considering the severe impacts of genetic bottlenecks and small numbers of founders in populations of reintroduced animals, it is necessary to study inbreeding and its effect on fitness in species of conservation concern. Pere David's deer is one of few large mammal species extinct in the wild but safely preserved in captivity. Its specific background gives us the opportunity to study the relationships between heterozygosity and neonatal fitness in relocated populations. We employed five microsatellite loci to explore heterozygosity-fitness correlations in a population of Pere David's deer at the Beijing Milu Ecological Research Center. We observed associations between microsatellite-based variables sMLH, IR, MD^2 and HL, and two components of fitness ex- pressed early in life (birth weight and the neonatal mortality of 123 Pere David's deer calves born over six consecutive years). We found that neonatal mortality was 19.1% - 7.6%, not higher than the 19% or 18% reported in other ungulates. The heterozygosity of calves was not associated with neonatal mortality, nor birth weight. Our study implies that low genetic variability of microsa- l:ellite loci has no overt effect on birth weight and neonatal mortality in reintroduced populations of P^re David's deer [Current Zoology 59 (2): 249-256, 2013].展开更多
基金the RIT College of Liberal Arts Faculty Research Fund for supplemental funding that enabled presentation of the preliminary results at the above mentioned AERE Conference in Asheville, NC
文摘The purpose of this paper is to explore the promise of utilizing some relatively new feedback control techniques in ecosystem management. First, we set forth a basic ecological-economic model of a predator-prey-hunting system in which both the predator and prey have use(flow) and non-use(stock) value and when the predator can inflict transboundary damages. We then use new data from the US Mountain West to show how a particular feedback approach—linear parameter-varying(LPV) control—can be utilized in this context. Our LPV model is able to quantify the cost of managing disturbances that inevitably arise as a manager tries to keep the actual path of the system "close" to its optimum. The results suggest management strategies in mountain ecosystems that feature large, mammalian carnivores.
基金Acknowledgements Financial support for this work was provided by the National Natural Science Foundation of China (No. 31000174 & No. Jl103512). We thank Prof. Ding Yuhua and other staff members at Dafeng Milu National Natural Reserve for supporting our field research in the reserve. We also thank Xianlong Li, Rongrong Wang, Jia He, Dameng Li, Ruonan Jia, Yilei Hua, and Long Wang for help with the field work, and Chen Ge and Cheng Huang for useful discussions.
文摘After being kept in captivity and isolated from natural predators for more than 1,200 years, P6re David's deer has been reintroduced in China and now occurs in a reserve where human activity is the only potential threat. Antipredator vigilance i~ an important component of survival for many prey animals in their natural habitat. Do deer still adjust vigilance as a function of risk after such a long period of relaxed predation pressure? Here, we examined vigilance levels in P6re David's deer groups as a function of group size, sex and level of human disturbance. The results showed that individual vigilance significantly decreased with group size in all-female groups but not in all-males or mixed-sex groups. In rutting season, males compete with one another and harass females, and we argue that vigilance is partly aimed at threatening males and that such vigilance increases with group size. This explains why overall vigilance did not vary with group size for males in general and for females in mixed-sex groups. Vigilance increased in more disturbed areas but in in male deer only. The results indicate that despite relaxed predation pressure over centuries, P6re David's deer can still adjust antipredator responses as a function of perceived risk. Such information may become useful in the rewilding programme now under way for this species in China [Current Zoology 59 (2): 265-270, 2013].
文摘The reintroduction of rare and endangered species is one of the most important approaches to conservation and ecosystem restoration,but it has still proven to be an adventurous undertaking and most reintroduction programmes fail,so successful demonstrations are needed.Père David’s deer(Elaphurus davidianus,Milu in Chinese)could be considered one of conservation’s great success stories,as this species’path on the road to extinction has been reversed by a combination of ex-situ conservation and successful re-introduction in China.The species had been consigned to an imperial hunting ground when the last Chinese herds were exterminated during the fall of the Qing Dynasty(1644-1912).Fortunately,a few of the last remaining individuals were sent to European zoos.From these animals,a herd was bred on the 14;Duke of Bedford’s estate,Woburn Abbey,and between 1985and 1987,and 38 Milu were donated back to China for re-introduction in Beijing Milu Park(BMP),the former imperial hunting ground.An additional 39 deer were released at Dafeng National Nature Reserve(DFNNR),Jiangsu Province in 1986.In both of these safe and protected locations,the Milu thrived allowing for over 700 Milu to be sent to a further 82 sites throughout the species’original Chinese range over the last 36 years.As a result,the Milu population totaled 9136 by 2021,with 2855 individuals now living back in the wild;while another 5681 individuals inhabit the DFNNR,and 186 reside in BMP.Wild Milu,however,still face significant conservation challenges.The population lacks genetic diversity,leading to severe inbreeding depression and carrying multiple risks,such as high miscarriage rates,a reduced lifespan,and susceptibility to disease.Environmental constraints such as pollution and habitat fragmentation further result in small,fragmented wild populations.Moreover,the species currently lacks a national level conservation master plan,the associated coordinated monitoring platforms,and breeding plans for China’s captive populations.Finally,there is now a lack of international cooperation in the conservation of this species.We therefore call for both a national-level conservation master plan in China and international cooperation to develop a shared database and germplasm databank covering Milu across all countries with ex-situ populations,as crucial steps for securing the long-term conservation of Milu and preventing it from ever becoming“extinct in the wild”again.
文摘Considering the severe impacts of genetic bottlenecks and small numbers of founders in populations of reintroduced animals, it is necessary to study inbreeding and its effect on fitness in species of conservation concern. Pere David's deer is one of few large mammal species extinct in the wild but safely preserved in captivity. Its specific background gives us the opportunity to study the relationships between heterozygosity and neonatal fitness in relocated populations. We employed five microsatellite loci to explore heterozygosity-fitness correlations in a population of Pere David's deer at the Beijing Milu Ecological Research Center. We observed associations between microsatellite-based variables sMLH, IR, MD^2 and HL, and two components of fitness ex- pressed early in life (birth weight and the neonatal mortality of 123 Pere David's deer calves born over six consecutive years). We found that neonatal mortality was 19.1% - 7.6%, not higher than the 19% or 18% reported in other ungulates. The heterozygosity of calves was not associated with neonatal mortality, nor birth weight. Our study implies that low genetic variability of microsa- l:ellite loci has no overt effect on birth weight and neonatal mortality in reintroduced populations of P^re David's deer [Current Zoology 59 (2): 249-256, 2013].