Erik Doerr - Academia.edu (original) (raw)

Papers by Erik Doerr

Does structural connectivity facilitate dispersal of native species in Australia’s fragmented ter... more Does structural connectivity facilitate dispersal of native species in Australia’s fragmented terrestrial landscapes? Systematic review Reviewer(s) Date draft protocol published on website Date final protocol published on website Date of most recent amendment Date of most recent SUBSTANTIVE amendment Details of most recent changes Contact address

Biological Conservation, 2017

Managing and restoring connectivity that enables wildlife movement through landscapes is the prim... more Managing and restoring connectivity that enables wildlife movement through landscapes is the primary approach to reduce harmful effects of habitat loss and fragmentation. Improved connectivity is also increasingly invoked as a strategy to mitigate negative impacts of climate change by enabling species to track preferred environments and maintain evolutionary processes. Although initiatives to improve connectivity using restoration are becoming commonplace, we do not know how successful these actions are, nor which mechanisms underlie biotic responses. Most ecological monitoring focuses on site condition or quality rather than those landscape-scale processes that connectivity is intended to facilitate. To assess biodiversity responses to connectivity initiatives, we argue that new monitoring approaches are needed that distinguish the roles of connectivity restoration from those of habitat augmentation or improvement. To address this critical gap, we developed a conceptual model of the hypothesised roles of connectivity in complex landscapes and a linked framework to guide design of connectivity monitoring approaches in an adaptive management context. We demonstrate that integrated monitoring approaches using complementary methods are essential to reveal whether long-term landscape-scale goals are being achieved, and to determine whether connectivity management and restoration are the mechanisms responsible. We summarize a real-world example of applying our approach to assist government develop a monitoring plan for a large-scale connectivity conservation initiative in the Australian Capital Territory. As well as highlighting the utility of the framework to help managers make informed choices about monitoring, this example illustrates the difficulties of convincing funding bodies to include monitoring in project budgets and the questions more likely to be answered with limited funds. Synthesis and applications. Implementing an effective strategy to monitor connectivity conservation initiatives necessarily involves more work but we argue it is an essential investment rather than an additional cost. By optimizing allocation of limited monitoring resources, we can more effectively implement management that improves functional connectivity, and understand how changing connectivity affects population persistence.

Behavioural Processes, 2007

In cooperative breeding systems, some individuals help to raise offspring that are not their own.... more In cooperative breeding systems, some individuals help to raise offspring that are not their own. While early explanations for such altruistic behaviour were predominantly based on kin selection, recent evidence suggests that direct benefits may be important in the maintenance of cooperation. To date, however, discussions of cooperative breeding have made little reference to more general theories of cooperation between unrelated individuals (while these theories rarely address cooperative breeding). Here, we attempt to integrate the two fields. We identify four key questions that can be used to categorise different mechanisms for the maintenance of cooperative behaviour: (1) whether or not individuals invest in others; (2) whether or not this initial investment elicits a return investment by the beneficiary; (3) whether the interaction is direct, i.e. between two partners, or indirect (involving third parties) and (4) whether only actions that increase the fitness of the partner or also fitness reducing actions (punishment) are involved in the interaction. Asking these questions with regards to concepts in the literature on cooperative breeding, we found that (a) it is often straightforward to relate these concepts to general mechanisms of cooperation, but that (b) a single term (such as 'pay-to-stay', 'group augmentation' or 'prestige') may sometimes subsume two or more distinct mechanisms, and that (c) at least some mechanisms that are thought to be important in cooperative breeding systems have remained largely unexplored in the theoretical literature on the evolution of cooperation. Future theoretical models should incorporate asymmetries in power and pay off structure caused for instance by dominance hierarchies or partner choice, and the use of N-player games. The key challenges for both theoreticians and empiricists will be to integrate the hitherto disparate fields and to disentangle the parallel effects of kin and non-kin based mechanisms of cooperation.

Journal for Nature Conservation, 2015

Despite the proliferation of connectivity modelling approaches, static models have limited useful... more Despite the proliferation of connectivity modelling approaches, static models have limited usefulness for decision-making by policy-makers and land managers, particularly where significant changes in land uses might be expected into the future. This study presents a flexible, scenario-based approach for modelling fine-scaled connectivity using graph-theory with least-cost paths for modelling connectivity at the regional scale and Circuit theory at the local scale. The method allows for the assessment of a range of scenarios based on varying land use practices. Using the Lower Hunter region, Australia as a case study we tested five scenarios that describe the impact of different development choices on connectivity, ranging from high rates of urbanisation to revegetation of a designated green corridor. The changes in connectivity from the current state were assessed by visualising component boundaries and link locations and calculating patch-and landscape-scale graph metrics. In the Lower Hunter we found the green corridor scenario increased connectivity both visually and quantitatively as shown by a 105% increase in the integral index of connectivity (IIC) which measures habitat availability (reachability) at the landscape scale. While the urbanisation scenario resulted in a decrease in connectivity, with a 39% decrease in the IIC. The approach outlined in this paper is flexible, enabling a range of interests to be included, depending on the datasets available and the issues that need to be addressed. Such methods can be readily and rapidly applied by consultants or government agencies, in this region and elsewhere, to incorporate connectivity modelling into development plans.

Western Birds

A number of characteristics contribute to the difficulties involved in capturing Black-billed Mag... more A number of characteristics contribute to the difficulties involved in capturing Black-billed Magpies (Pica pica). They are extremely wary, tend- ing to avoid unusual objects (e.g., wire traps or mist-net poles) that have been recently introduced into their environment. Some are particularly reluctant to walk into enclosed traps (Birkhead 1991, J. M. Marzluff pers. comm.). Magpies also tend to be opportunistic feeders, making it virtually impossible to predict flight paths for the placement of mist nets. Finally, they learn very quickly and will avoid any trap in which they have previously been caught or nearly caught. They may even avoid traps in which they have merely seen other birds captured. Researchers have coped with these problems in several ways. Variations of funnel-entrance traps (e.g., Alsager et al. 1972) have been used with considerable success in some populations (Erpino 1968, Reese and Kadlec 1985) but with little or no success in others (Birkhead 1991, J. M. Marzluf...

Landscape and Urban Planning, 2015

h i g h l i g h t s • We describe a multi-scale connectivity framework for conservation planning.... more h i g h l i g h t s • We describe a multi-scale connectivity framework for conservation planning. • The model characterises connectivity at fine resolutions over large spatial extents. • Graph networks are used at the regional scale and Circuitscape at the local scale. • The framework was designed specifically to be applied by landuse planners.

Molecular Ecology Notes, 2005

Eight polymorphic microsatellite markers were developed for the brown treecreeper, Climacteris pi... more Eight polymorphic microsatellite markers were developed for the brown treecreeper, Climacteris picumnus. The number of alleles ranged from three to 25 per locus with observed heterozygosities between 0.05 and 0.76. Seven of the eight primer pairs also amplified polymorphic microsatellite loci in the white-throated treecreeper (Cormobates leucophaeus). These markers are likely to be useful for population genetic and parentage studies in any of the Australasian treecreepers (Climacteridae) and are the first genetic markers developed for any member of this passerine family.

The role of NCCARF is to lead the research community in a national interdisciplinary effort to ge... more The role of NCCARF is to lead the research community in a national interdisciplinary effort to generate the information needed by decision-makers in government, business and in vulnerable sectors and communities to manage the risk of climate change impacts. Disclaimer The views expressed herein are not necessarily the views of the Commonwealth or NCCARF, and neither the Commonwealth nor NCCARF accept responsibility for information or advice contained herein. CSIRO advises that the information contained in this publication comprises general statements based on scientific research. The reader is advised and needs to be aware that such information may be incomplete or unable to be used in any specific situation. No reliance or actions must therefore be made on that information without seeking prior expert professional, scientific and technical advice. To the extent permitted by law, CSIRO (including its employees and consultants) excludes all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using this publication (in part or in whole) and any information or material contained in it.

A number of characteristics contribute to the difficulties involved in capturing Black-billed Mag... more A number of characteristics contribute to the difficulties involved in capturing Black-billed Magpies (Pica pica). They are extremely wary, tend- ing to avoid unusual objects (e.g., wire traps or mist-net poles) that have been recently introduced into their environment. Some are particularly reluctant to walk into enclosed traps (Birkhead 1991, J. M. Marzluff pers. comm.). Magpies also tend to be

International Journal of Applied Earth Observation and Geoinformation, 2010

Environmental sensor networks (ESNs) provide new opportunities for improving our understanding of... more Environmental sensor networks (ESNs) provide new opportunities for improving our understanding of the environment. In contrast to remote sensing technologies where measurements are made from large distances (e.g. satellite imagery, aerial photography, airborne radiometric surveys), ESNs focus on measurements that are made in close proximity to the target environmental phenomenon. Sensors can be used to collect a much larger number of measurements, which are quantitative and repeatable. They can also be deployed in locations that may otherwise be difficult to visit regularly. Sensors that are commonly used in the environmental sciences include ground-based multispectral vegetation sensors, soil moisture sensors, GPS tracking and bioacoustics for tracking movement in wild and domesticated animals. Sensors may also be coupled with wireless networks to more effectively capture, synthesise and transmit data to decision-makers. The climate and weather monitoring domains provide useful examples of how ESNs can provide real-time monitoring of environmental change (e.g. temperature, rainfall, sea-surface temperature) to many users. The objective of this review is to examine state-of-the-art use of ESNs for three environmental monitoring domains: (a) terrestrial vegetation, (b) animal movement and diversity, and (c) soil. Climate and aquatic monitoring sensor applications are so extensive that they are beyond the scope of this review. In each of the three application domains (vegetation, animals and soils) we review the technologies, the attributes that they sense and briefly examine the technical limitations. We conclude with a discussion of future directions.

Plos One, 2013

Habitat restoration can play an important role in recovering functioning ecosystems and improving... more Habitat restoration can play an important role in recovering functioning ecosystems and improving biodiversity. Restoration may be particularly important in improving habitat prior to species reintroductions. We reintroduced seven brown treecreeper (Climacteris picumnus) social groups into two nature reserves in the Australian Capital Territory in southeastern Australia. This study provided a unique opportunity to understand the interactions between restoration ecology, behavioural ecology and habitat ecology. We examined how experimental restoration treatments (addition of coarse woody debris, variations in ground vegetation cover and nest box installation) influenced the behaviour and microhabitat use of radio-tracked individuals to evaluate the success of restoration treatments. The addition of coarse woody debris benefited the brown treecreeper through increasing the probability of foraging on a log or on the ground. This demonstrated the value of using behaviour as a bio-indicator for restoration success. Based on previous research, we predicted that variations in levels of ground vegetation cover would influence behaviour and substrate use, particularly that brown treecreepers would choose sites with sparse ground cover because this allows better access to food and better vigilance for predators. However, there was little effect of this treatment, which was likely influenced by the limited overall use of the ground layer. There was also little effect of nest boxes on behaviour or substrate use. These results somewhat confound our understanding of the species based on research from extant populations. Our results also have a significant impact regarding using existing knowledge on a species to inform how it will respond to reintroduction and habitat restoration. This study also places great emphasis on the value of applying an experimental framework to ecological restoration, particularly when reintroductions produce unexpected outcomes.

Austral Ecology, 2014

Funding was provided by LWA, the CSIRO and the Victorian Department of Sustainability and Environ... more Funding was provided by LWA, the CSIRO and the Victorian Department of Sustainability and Environment.

Does structural connectivity facilitate dispersal of native species in Australia's fragmented... more Does structural connectivity facilitate dispersal of native species in Australia's fragmented terrestrial landscapes? CEE protocol 08-007 (SR44).

The Wilson Bulletin, 2001

PLoS ONE, 2012

It is essential to choose suitable habitat when reintroducing a species into its former range. Ha... more It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual's dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes) influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals) of the brown treecreeper (Climacteris picumnus) into two nature reserves in southeastern Australia. We radiotracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual's gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species' requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides), which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals, particularly when based on current knowledge of a species' ecology.

Oecologia, 2004

A complete understanding of animal dispersal requires knowledge not only of its consequences at p... more A complete understanding of animal dispersal requires knowledge not only of its consequences at population and community levels, but also of the behavioural decisions made by dispersing individuals. Recent theoretical work has emphasised the importance of this dispersal process, particularly the phase in which individuals search the landscape for breeding opportunities. However, empirical advances are currently hampered by a lack of tools for quantifying these dispersal search tactics. Here, we review existing methods for quantifying movement that are appropriate for the dispersal search process, describe several new techniques that we developed for characterising movement and behaviour through an individual's dispersal range, and illustrate their use with data from Australasian treecreepers (Climacteridae). We also describe how the quantitative parameters we discuss are calculated in a freely available computer software package that we designed. Specifically, we present methods for calculating the area searched during dispersal, search rate, thoroughness, intensity, philopatry of search, timing of exploration, and surreptitiousness. When we applied this approach to the study of dispersal in treecreepers, we found that search area, philopatry and timing of exploration showed the greatest individual variation. Furthermore, search area, search rate, thoroughness and philopatry of search were all correlated, suggesting they may be useful parameters for further research on the causes and consequences of different dispersal search tactics. Finally, we make recommendations for modifying radiotracking protocols to facilitate more accurate assessment of individual variation in the dispersal process, and suggest future directions for this type of empirical work at the interface of population and behavioural ecology.

Does structural connectivity facilitate dispersal of native species in Australia’s fragmented ter... more Does structural connectivity facilitate dispersal of native species in Australia’s fragmented terrestrial landscapes? Systematic review Reviewer(s) Date draft protocol published on website Date final protocol published on website Date of most recent amendment Date of most recent SUBSTANTIVE amendment Details of most recent changes Contact address

Biological Conservation, 2017

Managing and restoring connectivity that enables wildlife movement through landscapes is the prim... more Managing and restoring connectivity that enables wildlife movement through landscapes is the primary approach to reduce harmful effects of habitat loss and fragmentation. Improved connectivity is also increasingly invoked as a strategy to mitigate negative impacts of climate change by enabling species to track preferred environments and maintain evolutionary processes. Although initiatives to improve connectivity using restoration are becoming commonplace, we do not know how successful these actions are, nor which mechanisms underlie biotic responses. Most ecological monitoring focuses on site condition or quality rather than those landscape-scale processes that connectivity is intended to facilitate. To assess biodiversity responses to connectivity initiatives, we argue that new monitoring approaches are needed that distinguish the roles of connectivity restoration from those of habitat augmentation or improvement. To address this critical gap, we developed a conceptual model of the hypothesised roles of connectivity in complex landscapes and a linked framework to guide design of connectivity monitoring approaches in an adaptive management context. We demonstrate that integrated monitoring approaches using complementary methods are essential to reveal whether long-term landscape-scale goals are being achieved, and to determine whether connectivity management and restoration are the mechanisms responsible. We summarize a real-world example of applying our approach to assist government develop a monitoring plan for a large-scale connectivity conservation initiative in the Australian Capital Territory. As well as highlighting the utility of the framework to help managers make informed choices about monitoring, this example illustrates the difficulties of convincing funding bodies to include monitoring in project budgets and the questions more likely to be answered with limited funds. Synthesis and applications. Implementing an effective strategy to monitor connectivity conservation initiatives necessarily involves more work but we argue it is an essential investment rather than an additional cost. By optimizing allocation of limited monitoring resources, we can more effectively implement management that improves functional connectivity, and understand how changing connectivity affects population persistence.

Behavioural Processes, 2007

In cooperative breeding systems, some individuals help to raise offspring that are not their own.... more In cooperative breeding systems, some individuals help to raise offspring that are not their own. While early explanations for such altruistic behaviour were predominantly based on kin selection, recent evidence suggests that direct benefits may be important in the maintenance of cooperation. To date, however, discussions of cooperative breeding have made little reference to more general theories of cooperation between unrelated individuals (while these theories rarely address cooperative breeding). Here, we attempt to integrate the two fields. We identify four key questions that can be used to categorise different mechanisms for the maintenance of cooperative behaviour: (1) whether or not individuals invest in others; (2) whether or not this initial investment elicits a return investment by the beneficiary; (3) whether the interaction is direct, i.e. between two partners, or indirect (involving third parties) and (4) whether only actions that increase the fitness of the partner or also fitness reducing actions (punishment) are involved in the interaction. Asking these questions with regards to concepts in the literature on cooperative breeding, we found that (a) it is often straightforward to relate these concepts to general mechanisms of cooperation, but that (b) a single term (such as 'pay-to-stay', 'group augmentation' or 'prestige') may sometimes subsume two or more distinct mechanisms, and that (c) at least some mechanisms that are thought to be important in cooperative breeding systems have remained largely unexplored in the theoretical literature on the evolution of cooperation. Future theoretical models should incorporate asymmetries in power and pay off structure caused for instance by dominance hierarchies or partner choice, and the use of N-player games. The key challenges for both theoreticians and empiricists will be to integrate the hitherto disparate fields and to disentangle the parallel effects of kin and non-kin based mechanisms of cooperation.

Journal for Nature Conservation, 2015

Despite the proliferation of connectivity modelling approaches, static models have limited useful... more Despite the proliferation of connectivity modelling approaches, static models have limited usefulness for decision-making by policy-makers and land managers, particularly where significant changes in land uses might be expected into the future. This study presents a flexible, scenario-based approach for modelling fine-scaled connectivity using graph-theory with least-cost paths for modelling connectivity at the regional scale and Circuit theory at the local scale. The method allows for the assessment of a range of scenarios based on varying land use practices. Using the Lower Hunter region, Australia as a case study we tested five scenarios that describe the impact of different development choices on connectivity, ranging from high rates of urbanisation to revegetation of a designated green corridor. The changes in connectivity from the current state were assessed by visualising component boundaries and link locations and calculating patch-and landscape-scale graph metrics. In the Lower Hunter we found the green corridor scenario increased connectivity both visually and quantitatively as shown by a 105% increase in the integral index of connectivity (IIC) which measures habitat availability (reachability) at the landscape scale. While the urbanisation scenario resulted in a decrease in connectivity, with a 39% decrease in the IIC. The approach outlined in this paper is flexible, enabling a range of interests to be included, depending on the datasets available and the issues that need to be addressed. Such methods can be readily and rapidly applied by consultants or government agencies, in this region and elsewhere, to incorporate connectivity modelling into development plans.

Western Birds

A number of characteristics contribute to the difficulties involved in capturing Black-billed Mag... more A number of characteristics contribute to the difficulties involved in capturing Black-billed Magpies (Pica pica). They are extremely wary, tend- ing to avoid unusual objects (e.g., wire traps or mist-net poles) that have been recently introduced into their environment. Some are particularly reluctant to walk into enclosed traps (Birkhead 1991, J. M. Marzluff pers. comm.). Magpies also tend to be opportunistic feeders, making it virtually impossible to predict flight paths for the placement of mist nets. Finally, they learn very quickly and will avoid any trap in which they have previously been caught or nearly caught. They may even avoid traps in which they have merely seen other birds captured. Researchers have coped with these problems in several ways. Variations of funnel-entrance traps (e.g., Alsager et al. 1972) have been used with considerable success in some populations (Erpino 1968, Reese and Kadlec 1985) but with little or no success in others (Birkhead 1991, J. M. Marzluf...

Landscape and Urban Planning, 2015

h i g h l i g h t s • We describe a multi-scale connectivity framework for conservation planning.... more h i g h l i g h t s • We describe a multi-scale connectivity framework for conservation planning. • The model characterises connectivity at fine resolutions over large spatial extents. • Graph networks are used at the regional scale and Circuitscape at the local scale. • The framework was designed specifically to be applied by landuse planners.

Molecular Ecology Notes, 2005

Eight polymorphic microsatellite markers were developed for the brown treecreeper, Climacteris pi... more Eight polymorphic microsatellite markers were developed for the brown treecreeper, Climacteris picumnus. The number of alleles ranged from three to 25 per locus with observed heterozygosities between 0.05 and 0.76. Seven of the eight primer pairs also amplified polymorphic microsatellite loci in the white-throated treecreeper (Cormobates leucophaeus). These markers are likely to be useful for population genetic and parentage studies in any of the Australasian treecreepers (Climacteridae) and are the first genetic markers developed for any member of this passerine family.

The role of NCCARF is to lead the research community in a national interdisciplinary effort to ge... more The role of NCCARF is to lead the research community in a national interdisciplinary effort to generate the information needed by decision-makers in government, business and in vulnerable sectors and communities to manage the risk of climate change impacts. Disclaimer The views expressed herein are not necessarily the views of the Commonwealth or NCCARF, and neither the Commonwealth nor NCCARF accept responsibility for information or advice contained herein. CSIRO advises that the information contained in this publication comprises general statements based on scientific research. The reader is advised and needs to be aware that such information may be incomplete or unable to be used in any specific situation. No reliance or actions must therefore be made on that information without seeking prior expert professional, scientific and technical advice. To the extent permitted by law, CSIRO (including its employees and consultants) excludes all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using this publication (in part or in whole) and any information or material contained in it.

A number of characteristics contribute to the difficulties involved in capturing Black-billed Mag... more A number of characteristics contribute to the difficulties involved in capturing Black-billed Magpies (Pica pica). They are extremely wary, tend- ing to avoid unusual objects (e.g., wire traps or mist-net poles) that have been recently introduced into their environment. Some are particularly reluctant to walk into enclosed traps (Birkhead 1991, J. M. Marzluff pers. comm.). Magpies also tend to be

International Journal of Applied Earth Observation and Geoinformation, 2010

Environmental sensor networks (ESNs) provide new opportunities for improving our understanding of... more Environmental sensor networks (ESNs) provide new opportunities for improving our understanding of the environment. In contrast to remote sensing technologies where measurements are made from large distances (e.g. satellite imagery, aerial photography, airborne radiometric surveys), ESNs focus on measurements that are made in close proximity to the target environmental phenomenon. Sensors can be used to collect a much larger number of measurements, which are quantitative and repeatable. They can also be deployed in locations that may otherwise be difficult to visit regularly. Sensors that are commonly used in the environmental sciences include ground-based multispectral vegetation sensors, soil moisture sensors, GPS tracking and bioacoustics for tracking movement in wild and domesticated animals. Sensors may also be coupled with wireless networks to more effectively capture, synthesise and transmit data to decision-makers. The climate and weather monitoring domains provide useful examples of how ESNs can provide real-time monitoring of environmental change (e.g. temperature, rainfall, sea-surface temperature) to many users. The objective of this review is to examine state-of-the-art use of ESNs for three environmental monitoring domains: (a) terrestrial vegetation, (b) animal movement and diversity, and (c) soil. Climate and aquatic monitoring sensor applications are so extensive that they are beyond the scope of this review. In each of the three application domains (vegetation, animals and soils) we review the technologies, the attributes that they sense and briefly examine the technical limitations. We conclude with a discussion of future directions.

Plos One, 2013

Habitat restoration can play an important role in recovering functioning ecosystems and improving... more Habitat restoration can play an important role in recovering functioning ecosystems and improving biodiversity. Restoration may be particularly important in improving habitat prior to species reintroductions. We reintroduced seven brown treecreeper (Climacteris picumnus) social groups into two nature reserves in the Australian Capital Territory in southeastern Australia. This study provided a unique opportunity to understand the interactions between restoration ecology, behavioural ecology and habitat ecology. We examined how experimental restoration treatments (addition of coarse woody debris, variations in ground vegetation cover and nest box installation) influenced the behaviour and microhabitat use of radio-tracked individuals to evaluate the success of restoration treatments. The addition of coarse woody debris benefited the brown treecreeper through increasing the probability of foraging on a log or on the ground. This demonstrated the value of using behaviour as a bio-indicator for restoration success. Based on previous research, we predicted that variations in levels of ground vegetation cover would influence behaviour and substrate use, particularly that brown treecreepers would choose sites with sparse ground cover because this allows better access to food and better vigilance for predators. However, there was little effect of this treatment, which was likely influenced by the limited overall use of the ground layer. There was also little effect of nest boxes on behaviour or substrate use. These results somewhat confound our understanding of the species based on research from extant populations. Our results also have a significant impact regarding using existing knowledge on a species to inform how it will respond to reintroduction and habitat restoration. This study also places great emphasis on the value of applying an experimental framework to ecological restoration, particularly when reintroductions produce unexpected outcomes.

Austral Ecology, 2014

Funding was provided by LWA, the CSIRO and the Victorian Department of Sustainability and Environ... more Funding was provided by LWA, the CSIRO and the Victorian Department of Sustainability and Environment.

Does structural connectivity facilitate dispersal of native species in Australia's fragmented... more Does structural connectivity facilitate dispersal of native species in Australia's fragmented terrestrial landscapes? CEE protocol 08-007 (SR44).

The Wilson Bulletin, 2001

PLoS ONE, 2012

It is essential to choose suitable habitat when reintroducing a species into its former range. Ha... more It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual's dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes) influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals) of the brown treecreeper (Climacteris picumnus) into two nature reserves in southeastern Australia. We radiotracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual's gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species' requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides), which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals, particularly when based on current knowledge of a species' ecology.

Oecologia, 2004

A complete understanding of animal dispersal requires knowledge not only of its consequences at p... more A complete understanding of animal dispersal requires knowledge not only of its consequences at population and community levels, but also of the behavioural decisions made by dispersing individuals. Recent theoretical work has emphasised the importance of this dispersal process, particularly the phase in which individuals search the landscape for breeding opportunities. However, empirical advances are currently hampered by a lack of tools for quantifying these dispersal search tactics. Here, we review existing methods for quantifying movement that are appropriate for the dispersal search process, describe several new techniques that we developed for characterising movement and behaviour through an individual's dispersal range, and illustrate their use with data from Australasian treecreepers (Climacteridae). We also describe how the quantitative parameters we discuss are calculated in a freely available computer software package that we designed. Specifically, we present methods for calculating the area searched during dispersal, search rate, thoroughness, intensity, philopatry of search, timing of exploration, and surreptitiousness. When we applied this approach to the study of dispersal in treecreepers, we found that search area, philopatry and timing of exploration showed the greatest individual variation. Furthermore, search area, search rate, thoroughness and philopatry of search were all correlated, suggesting they may be useful parameters for further research on the causes and consequences of different dispersal search tactics. Finally, we make recommendations for modifying radiotracking protocols to facilitate more accurate assessment of individual variation in the dispersal process, and suggest future directions for this type of empirical work at the interface of population and behavioural ecology.