The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
David L. Morgan - One of the best experts on this subject based on the ideXlab platform.
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Important Refuge Habitats for threatened Balston’s Pygmy Perch in south-western Australia. Report to South West Catchments Council
2015Co-Authors: Mark G. Allen, Stephen J. Beatty, David L. MorganAbstract:The aim of this component of the study was to identify key Refuge Habitats for N. balstoni across its distributional range in order to prioritise Habitats for the conservation and management of the species. The results reported here should provide valuable data for authorities in developing management and recovery strategies for the conservation of this threatened south-western Australian endemic.
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important Refuge Habitats for threatened balston s pygmy perch in south western australia report to south west catchments council
Allen M.G. Beatty S.J. ORCID: 0000-0003-2620-2826 and Morgan D.L. (2015) Important refuge habitats for threatened Balston’s Pygmy Perch in south-weste, 2015Co-Authors: M Allen, S Beatty, David L. MorganAbstract:The aim of this component of the study was to identify key Refuge Habitats for N. balstoni across its distributional range in order to prioritise Habitats for the conservation and management of the species. The results reported here should provide valuable data for authorities in developing management and recovery strategies for the conservation of this threatened south-western Australian endemic.
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Adapting to climate change: A risk assessment and decision making framework for managing groundwater dependent ecosystems with declining water levels, Supporting Document 4: Environmental variables in the Habitats of southwestern Australian freshwate
2013Co-Authors: Stephen J. Beatty, David L. Morgan, James J. Keleher, Alan J. Lymbery, Paul Close, Peter Speldewinde, Tim Storer, A. KitsiosAbstract:Freshwater fishes have been used as indicators of aquatic ecosystem health as many teleosts are sensitive to water quality and habitat decline. Developing field derived thresholds, or tolerance indicator values (TIVs), based on matching distributions with prevailing water quality and habitat variables is a common approach that allows modelling of population viabilities under changing environmental conditions such as declines in water quality or hydrology. The freshwater fish fauna of south-western Australian is depauperate but has the highest rate of endemism of any Australian Drainage Division (82%). It is highly imperilled due to existing anthropogenic stressors such as secondary salinisation and riparian degradation. Secondary salinisation in particular has caused considerable inland range reductions of stenohaline species and the distributions of most are now limited to the western and southern parts of the region. The importance of fresh groundwater in maintaining lentic and lotic Refuge Habitats during the naturally dry summer and autumn in the region has also recently been recognised. For example, groundwater discharge during baseflow in the NCCARF project study area in the Blackwood River maintains habitat connectivity for the largest freshwater fish of the region, Tandanus bostocki and provides Refuge habitat for the nationally endangered Nannatherina balstoni. However, modelling future population viabilities under projected surface and groundwater level reduction scenarios has been limited by the lack of TIVs for most species. Therefore, the current study aimed to analyse an extensive database of fish distributions and water quality variables across south-western Australia (1098 sampling points) to develop TIVs for species that could then be used in a risk assessment and decision making framework for managing groundwater dependent ecosystems (GDEs) subjected to declining water levels in the Blackwood River. There were significant differences between species in TIVs relating to water temperature and conductivity. For example, some of the species that occupied narrow ranges and are considered to be threatened, such as Galaxiella munda and N.balstoni, occupied the coolest environments, whereas the common and widespread introduced Gambusia holbrooki and native Galaxias occidentalis occupied warmer and more saline environments. The findings from the current supporting document were subsequently incorporated into the Bayesian Belief Networks (Supporting Document 6) that modelled the likelihood of population declines for species following groundwater level reductions in the Blackwood River during baseflow. The BBNs were then mapped (Supporting Document 7) to spatially represent likelihood of population declines in the Blackwood River study area. The TIVs developed here will also be extremely useful for modelling population declines in response to other projected environmental changes in south-western Australia, such as increasing temperature and salinity.
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Groundwater intrusion maintains endemic freshwater fishes in South-Western Australia
2011Co-Authors: Stephen J. Beatty, David L. MorganAbstract:The freshwater fishes of the Southwest Coast Drainage Division of Australia are depauperate yet highly endemic. These fauna continue to be severely impacted by habitat alterations that have led to considerable population declines. In particular, secondary salinisation has recently been identified as a major cause of these range reductions of these species. Despite these declines, the role that fresh groundwater intrusions have on maintaining critical Refuge Habitats is poorly understood. Using two case studies from the Swan-Canning catchment and the Blackwood River, this presentation discusses how salinisation has led to range contractions of the freshwater fish fauna and concomitant inland expansions of estuarine species. It then presents findings from the long-term (five year) study into the relationships between freshwater fish movement patterns, habitat usage and prevailing environmental variables in the Blackwood River (the largest by discharge in the region). The study reveals clear relationships between surface and groundwater flow and ecology of freshwater fishes in this system and demonstrates that fresh groundwater intrusion plays a crucial role in maintaining threatened freshwater fish populations. Management implications are outlined in terms of setting ecologically sustainable levels of groundwater extractions from the south-west in light of continuing rainfall reductions due to climate change.
Jérôme Fournier - One of the best experts on this subject based on the ideXlab platform.
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Differences in home-range sizes of a bird species in its original, Refuge and substitution Habitats: challenges to conservation in anthropogenic Habitats
Biodiversity and Conservation, 2017Co-Authors: Laurent Godet, Clément Harmange, Matthieu Marquet, Emmanuel Joyeux, Jérôme FournierAbstract:In the current context of the anthropocene, the original Habitats of many species have been modified or destroyed. Animals may be forced to move from their original Habitats, either to Refuge Habitats that are suboptimal natural Habitats, or to substitution Habitats that are anthropogenic. The quality of Refuge Habitats may be lower than that of the original ones, whereas substitution Habitats may be of a similar or even better quality. Here, we test this hypothesis empirically, using the example of coastal populations of the bluethroat, Luscinina svecica namnetum. In a radio-tracking survey, we compared the home-range sizes (considered here a proxy of habitat quality) of the breeding males in their original (coastal saltmarshes), Refuge (inland reedbeds) and substitution (coastal salinas) Habitats. We found that home ranges are up to 15 times larger in the substitution habitat than in the original one, and intermediate in the Refuge habitat, suggesting that substitution Habitats have the lowest quality and original Habitats the highest. To date, most studies and conservation programs related to this species have focused on its substitution Habitats. This result challenges the interest of focusing on anthropogenic Habitats when studying and conserving such a species, because such Habitats may only be low-quality substitutes.
Bertrand Gauffre - One of the best experts on this subject based on the ideXlab platform.
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How the common vole copes with modern farming: insights from a capture-mark-recapture experiment
Agriculture Ecosystems and Environment, 2013Co-Authors: Timothée Bonnet, Laurent Crespin, Adrien Pinot, Laurent Bruneteau, Vincent Bretagnolle, Bertrand GauffreAbstract:In this study, using capture-mark-recapture (CMR), a common vole population was monitored for one year in an experimental study site dominated by meadows, in which field management followed a gradient of intensiveness. The aim was to estimate the demographic response to agricultural practices of the common vole. During the spring, the numbers captured were highest in the most intensively managed plots. After cereal harvesting, they were higher in meadows with the highest nitrogen input. No difference in survival was found among treatments. However, the pattern of transitions suggested that high mobility explained this result. Also, mechanical interventions like ploughing appeared to have powerful consequences for common vole survival. These results underline the critical role of dispersal and Refuge Habitats in the maintenance of populations of voles in agroecosystems.
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How the common vole copes with modern farming: Insights from a capture–mark–recapture experiment
Agriculture Ecosystems & Environment, 2013Co-Authors: Timothée Bonnet, Laurent Crespin, Adrien Pinot, Laurent Bruneteau, Vincent Bretagnolle, Bertrand GauffreAbstract:Abstract In this study, using capture–mark–recapture (CMR), a common vole population was monitored for one year in an experimental study site dominated by meadows, in which field management followed a gradient of intensiveness. The aim was to estimate the demographic response to agricultural practices of the common vole. During the spring, the numbers captured were highest in the most intensively managed plots. After cereal harvesting, they were higher in meadows with the highest nitrogen input. No difference in survival was found among treatments. However, the pattern of transitions suggested that high mobility explained this result. Also, mechanical interventions like ploughing appeared to have powerful consequences for common vole survival. These results underline the critical role of dispersal and Refuge Habitats in the maintenance of populations of voles in agroecosystems.
Laurent Godet - One of the best experts on this subject based on the ideXlab platform.
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Differences in home-range sizes of a bird species in its original, Refuge and substitution Habitats: challenges to conservation in anthropogenic Habitats
Biodiversity and Conservation, 2017Co-Authors: Laurent Godet, Clément Harmange, Matthieu Marquet, Emmanuel Joyeux, Jérôme FournierAbstract:In the current context of the anthropocene, the original Habitats of many species have been modified or destroyed. Animals may be forced to move from their original Habitats, either to Refuge Habitats that are suboptimal natural Habitats, or to substitution Habitats that are anthropogenic. The quality of Refuge Habitats may be lower than that of the original ones, whereas substitution Habitats may be of a similar or even better quality. Here, we test this hypothesis empirically, using the example of coastal populations of the bluethroat, Luscinina svecica namnetum. In a radio-tracking survey, we compared the home-range sizes (considered here a proxy of habitat quality) of the breeding males in their original (coastal saltmarshes), Refuge (inland reedbeds) and substitution (coastal salinas) Habitats. We found that home ranges are up to 15 times larger in the substitution habitat than in the original one, and intermediate in the Refuge habitat, suggesting that substitution Habitats have the lowest quality and original Habitats the highest. To date, most studies and conservation programs related to this species have focused on its substitution Habitats. This result challenges the interest of focusing on anthropogenic Habitats when studying and conserving such a species, because such Habitats may only be low-quality substitutes.
Timothée Bonnet - One of the best experts on this subject based on the ideXlab platform.
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How the common vole copes with modern farming: insights from a capture-mark-recapture experiment
Agriculture Ecosystems and Environment, 2013Co-Authors: Timothée Bonnet, Laurent Crespin, Adrien Pinot, Laurent Bruneteau, Vincent Bretagnolle, Bertrand GauffreAbstract:In this study, using capture-mark-recapture (CMR), a common vole population was monitored for one year in an experimental study site dominated by meadows, in which field management followed a gradient of intensiveness. The aim was to estimate the demographic response to agricultural practices of the common vole. During the spring, the numbers captured were highest in the most intensively managed plots. After cereal harvesting, they were higher in meadows with the highest nitrogen input. No difference in survival was found among treatments. However, the pattern of transitions suggested that high mobility explained this result. Also, mechanical interventions like ploughing appeared to have powerful consequences for common vole survival. These results underline the critical role of dispersal and Refuge Habitats in the maintenance of populations of voles in agroecosystems.
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How the common vole copes with modern farming: Insights from a capture–mark–recapture experiment
Agriculture Ecosystems & Environment, 2013Co-Authors: Timothée Bonnet, Laurent Crespin, Adrien Pinot, Laurent Bruneteau, Vincent Bretagnolle, Bertrand GauffreAbstract:Abstract In this study, using capture–mark–recapture (CMR), a common vole population was monitored for one year in an experimental study site dominated by meadows, in which field management followed a gradient of intensiveness. The aim was to estimate the demographic response to agricultural practices of the common vole. During the spring, the numbers captured were highest in the most intensively managed plots. After cereal harvesting, they were higher in meadows with the highest nitrogen input. No difference in survival was found among treatments. However, the pattern of transitions suggested that high mobility explained this result. Also, mechanical interventions like ploughing appeared to have powerful consequences for common vole survival. These results underline the critical role of dispersal and Refuge Habitats in the maintenance of populations of voles in agroecosystems.