Avian functional responses to landscape recovery
- Ikin, Karen, Barton, Philip, Blanchard, Wade, Crane, Mason, Stein, John, Lindenmayer, David
- Authors: Ikin, Karen , Barton, Philip , Blanchard, Wade , Crane, Mason , Stein, John , Lindenmayer, David
- Date: 2019
- Type: Text , Journal article
- Relation: Proceedings of the Royal Society B: Biological Sciences Vol. 286, no. 1901 (2019), p.
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- Description: Restoring native vegetation in agricultural landscapes can reverse biodiversity declines via species gains. Depending on whether the traits of colonizers are complementary or redundant to the assemblage, species gains can increase the efficiency or stability of ecological functions, yet detecting these processes is not straightforward.We propose a new conceptual model to identify potential changes to complementarity and redundancy in response to landscape change via relative changes in taxonomic and functional richness.We applied our model to a 14-year study of birds across an extensive agricultural region. We found compelling evidence that high levels of landscape-scale tree cover and patch-scale restoration were significant determinants of functional change in the overall bird assemblage. This was true for every one of the six traits investigated individually, indicating increased trait-specific functional complementarity and redundancy in the assemblage. Applying our conceptual model to species diversity data provided new insights into how the return of vertebrates to restored landscapes may affect ecological function. © 2019 The Author(s).
- Authors: Ikin, Karen , Barton, Philip , Blanchard, Wade , Crane, Mason , Stein, John , Lindenmayer, David
- Date: 2019
- Type: Text , Journal article
- Relation: Proceedings of the Royal Society B: Biological Sciences Vol. 286, no. 1901 (2019), p.
- Full Text:
- Reviewed:
- Description: Restoring native vegetation in agricultural landscapes can reverse biodiversity declines via species gains. Depending on whether the traits of colonizers are complementary or redundant to the assemblage, species gains can increase the efficiency or stability of ecological functions, yet detecting these processes is not straightforward.We propose a new conceptual model to identify potential changes to complementarity and redundancy in response to landscape change via relative changes in taxonomic and functional richness.We applied our model to a 14-year study of birds across an extensive agricultural region. We found compelling evidence that high levels of landscape-scale tree cover and patch-scale restoration were significant determinants of functional change in the overall bird assemblage. This was true for every one of the six traits investigated individually, indicating increased trait-specific functional complementarity and redundancy in the assemblage. Applying our conceptual model to species diversity data provided new insights into how the return of vertebrates to restored landscapes may affect ecological function. © 2019 The Author(s).
- Ng, Katherine, Barton, Philip, Macfadyen, Sarina, Lindenmayer, David, Driscoll, Don
- Authors: Ng, Katherine , Barton, Philip , Macfadyen, Sarina , Lindenmayer, David , Driscoll, Don
- Date: 2018
- Type: Text , Journal article
- Relation: Landscape Ecology Vol. 33, no. 1 (2018), p. 109-125
- Full Text: false
- Reviewed:
- Description: Context: Farming practices influence the degree of contrast between adjoining habitats, with consequences for biodiversity and species movement. Little is known, however, on insect community responses to different kinds of edges over time, and the extent of cross-habitat movement in agricultural landscapes. Objective: To determine temporal changes in beetle responses to different farmland-woodland edges, and document cross-habitat movement. Methods: We examined species richness, abundance, and movement across edges between remnant woodlands and four farmland uses (plantings, fallow, annual crops, woody debris applied over crops post-harvest) in southeastern Australia. We used directional pitfall traps to infer movement, and sampled at edges, and 20 and 200 m on both sides of edges, during spring and summer. Results: Detritivore and predator abundance varied between seasons across the edge between woodlands and all farmlands, but seasonal differences were weaker for fallow-woodland and woody debris-woodland edges. Detritivores moved from farmlands towards woodlands, but not across fallow-woodlands and woody debris-woodlands edges during summer. During summer, predators showed short-range movement towards edges from all farmlands except plantings, and towards woody debris from woodlands. Edges showed temporally stable predator richness and higher herbivore richness than adjoining habitats. Conclusions: Farmland use and season interactively affect beetle abundance across farmland-woodland edges. Woody debris can reduce seasonal fluctuations in beetle edge responses and increase permeability for cross-habitat movement, while plantings provide habitat during summer. Edges provide important resources for beetles in adjoining habitats, however, seasonal movement of predators specifically into edges may affect prey assemblages—a link requiring further study. © 2017, Springer Science+Business Media B.V.
Birds as surrogates for mammals and reptiles: Are patterns of cross-taxonomic associations stable over time in a human-modified landscape?
- Yong, Ding, Barton, Philip, Okada, Sachiko, Crane, Mason, Lindenmayer, David
- Authors: Yong, Ding , Barton, Philip , Okada, Sachiko , Crane, Mason , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Ecological Indicators Vol. 69, no. (2016), p. 152-164
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- Description: Cross-taxonomic surrogates can be feasible alternatives to direct measurements of biodiversity in conservation if validated with robust data and used with explicit goals. However, few studies of cross-taxonomic surrogates have examined how temporal changes in composition or richness in one taxon can drive variation in concordant patterns of diversity in another taxon, particularly in a dynamic and heavily modified landscape. We examined this problem by assessing changes in cross-taxonomic associations over time between the surrogate (birds) and target vertebrate taxa (mammals, reptiles) that demand high sampling effort, in a heterogeneous mosaic landscape comprising pine monoculture, eucalypt woodland remnants and agricultural land. Focussing on four study years (1999, 2001, 2011, 2013) from a dataset collected over 15 years, we: (1) investigated temporal changes in cross-taxonomic congruency among three animal taxa (2) explored how temporal variation in composition and species richness of each taxon might account for variation in cross-taxonomic congruency, and (3) identified habitat structural variables that are strongly correlated with species composition of each taxon. We found the strength of cross-taxonomic congruency varied between taxa in response to both landscape context and over time. Among the three taxa, overall correlations were weak but were consistently positive and strongest between birds and mammals, while correlations involving reptiles were usually weak and negative. We also found that stronger species richness and composition correlations between birds and mammals were not only more prevalent in woodland remnants in the agricultural matrix, but they also increased in strength over time. Temporal shifts in species composition differed in rate and extent among the taxa even though these shifts were significant over time, while important habitat structural correlates were seldom shared across taxa. Our study highlights the role of the landscape matrix and time in shaping animal communities and the resulting cross-taxonomic associations in the woodland remnants, especially after a major perturbation event (i.e. plantation establishment). In such dynamic landscapes, differing and taxon-specific shifts in species diversity over time can influence the strength, direction and consistency of cross-taxonomic correlations, therefore posing a 'temporal' problem for the use of surrogates like birds in monitoring and assessment of biodiversity, and conservation management practices in general. © 2016 Elsevier Ltd. All rights reserved.
- Authors: Yong, Ding , Barton, Philip , Okada, Sachiko , Crane, Mason , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Ecological Indicators Vol. 69, no. (2016), p. 152-164
- Full Text:
- Reviewed:
- Description: Cross-taxonomic surrogates can be feasible alternatives to direct measurements of biodiversity in conservation if validated with robust data and used with explicit goals. However, few studies of cross-taxonomic surrogates have examined how temporal changes in composition or richness in one taxon can drive variation in concordant patterns of diversity in another taxon, particularly in a dynamic and heavily modified landscape. We examined this problem by assessing changes in cross-taxonomic associations over time between the surrogate (birds) and target vertebrate taxa (mammals, reptiles) that demand high sampling effort, in a heterogeneous mosaic landscape comprising pine monoculture, eucalypt woodland remnants and agricultural land. Focussing on four study years (1999, 2001, 2011, 2013) from a dataset collected over 15 years, we: (1) investigated temporal changes in cross-taxonomic congruency among three animal taxa (2) explored how temporal variation in composition and species richness of each taxon might account for variation in cross-taxonomic congruency, and (3) identified habitat structural variables that are strongly correlated with species composition of each taxon. We found the strength of cross-taxonomic congruency varied between taxa in response to both landscape context and over time. Among the three taxa, overall correlations were weak but were consistently positive and strongest between birds and mammals, while correlations involving reptiles were usually weak and negative. We also found that stronger species richness and composition correlations between birds and mammals were not only more prevalent in woodland remnants in the agricultural matrix, but they also increased in strength over time. Temporal shifts in species composition differed in rate and extent among the taxa even though these shifts were significant over time, while important habitat structural correlates were seldom shared across taxa. Our study highlights the role of the landscape matrix and time in shaping animal communities and the resulting cross-taxonomic associations in the woodland remnants, especially after a major perturbation event (i.e. plantation establishment). In such dynamic landscapes, differing and taxon-specific shifts in species diversity over time can influence the strength, direction and consistency of cross-taxonomic correlations, therefore posing a 'temporal' problem for the use of surrogates like birds in monitoring and assessment of biodiversity, and conservation management practices in general. © 2016 Elsevier Ltd. All rights reserved.
Conservation conundrums and the challenges of managing unexplained declines of multiple species
- Lindenmayer, David, Wood, Jeff, MacGregor, Christopher, Foster, Claire, Barton, Philip
- Authors: Lindenmayer, David , Wood, Jeff , MacGregor, Christopher , Foster, Claire , Barton, Philip
- Date: 2018
- Type: Text , Journal article
- Relation: Biological Conservation Vol. 221, no. (2018), p. 279-292
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- Description: The conventional approach to conserving threatened biota is to identify drivers of decline, instigate actions to mitigate threatening processes, and monitor interventions to test their effectiveness and ensure target species recover. In Australia, predation by introduced predators is a threatening process for many native mammals. Here we report the results of a 15 year monitoring study in an iconic Australian reserve, Booderee National Park, where exotic Red Fox (Vulpes vulpes) populations have been controlled through an intensive poison baiting program since 2003. Unexpectedly, we documented the collapse of native mammal fauna during this period, including fully arboreal species that should be largely unaffected by fox predation – such as the nationally Vulnerable Greater Glider (Petauroides volans) and Common Ringtail Possum (Pseudocheirus peregrinus). We used path analysis to explore potential causes of these unexpected declines. We found no compelling evidence to support hypotheses that competition with increasing native species, native predator release, or increases in native herbivores underpinned mammal declines. Beyond the path analysis, data from other studies completed both inside Booderee National Park and outside (where intensive fox baiting does not occur yet depleted fauna species remain), allowed us to rule out several drivers of change. The temporal declines we documented for arboreal marsupials were not anticipated nor explained by any clear mechanism. We propose the use of experimentally-guided reintroductions and translocations to: (1) restore empty niches such as the currently vacant apex mammal predator niche, (2) reconstruct the now depleted arboreal marsupial guild, and (3) further test key hypotheses associated with mammal decline. We also suggest that given the potential for perverse outcomes following large-scale management interventions (even those where there is high confidence of success), wildlife managers should consider maintaining reference areas (where there is no management intervention). Finally, as the declines we documented were unexpected and rapid, there is a clear need to develop more sensitive early warning signals to alert conservation managers to impending problems, allowing them to alter management regimes before major declines occur. © 2018 Elsevier Ltd. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton is provided in this record**
- Authors: Lindenmayer, David , Wood, Jeff , MacGregor, Christopher , Foster, Claire , Barton, Philip
- Date: 2018
- Type: Text , Journal article
- Relation: Biological Conservation Vol. 221, no. (2018), p. 279-292
- Full Text:
- Reviewed:
- Description: The conventional approach to conserving threatened biota is to identify drivers of decline, instigate actions to mitigate threatening processes, and monitor interventions to test their effectiveness and ensure target species recover. In Australia, predation by introduced predators is a threatening process for many native mammals. Here we report the results of a 15 year monitoring study in an iconic Australian reserve, Booderee National Park, where exotic Red Fox (Vulpes vulpes) populations have been controlled through an intensive poison baiting program since 2003. Unexpectedly, we documented the collapse of native mammal fauna during this period, including fully arboreal species that should be largely unaffected by fox predation – such as the nationally Vulnerable Greater Glider (Petauroides volans) and Common Ringtail Possum (Pseudocheirus peregrinus). We used path analysis to explore potential causes of these unexpected declines. We found no compelling evidence to support hypotheses that competition with increasing native species, native predator release, or increases in native herbivores underpinned mammal declines. Beyond the path analysis, data from other studies completed both inside Booderee National Park and outside (where intensive fox baiting does not occur yet depleted fauna species remain), allowed us to rule out several drivers of change. The temporal declines we documented for arboreal marsupials were not anticipated nor explained by any clear mechanism. We propose the use of experimentally-guided reintroductions and translocations to: (1) restore empty niches such as the currently vacant apex mammal predator niche, (2) reconstruct the now depleted arboreal marsupial guild, and (3) further test key hypotheses associated with mammal decline. We also suggest that given the potential for perverse outcomes following large-scale management interventions (even those where there is high confidence of success), wildlife managers should consider maintaining reference areas (where there is no management intervention). Finally, as the declines we documented were unexpected and rapid, there is a clear need to develop more sensitive early warning signals to alert conservation managers to impending problems, allowing them to alter management regimes before major declines occur. © 2018 Elsevier Ltd. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton is provided in this record**
Contrasting beetle assemblage responses to cultivated farmlands and native woodlands in a dynamic agricultural landscape
- Ng, Katherina, Driscoll, Don, MacFadyen, Sarina, Barton, Philip, McIntyre, Sue, Lindenmayer, David
- Authors: Ng, Katherina , Driscoll, Don , MacFadyen, Sarina , Barton, Philip , McIntyre, Sue , Lindenmayer, David
- Date: 2017
- Type: Text , Journal article
- Relation: Ecosphere Vol. 8, no. 12 (2017), p.
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- Description: There is an urgent need to identify ways of managing agricultural landscapes for biodiversity conservation without reducing food production. Farming practices that consider spatiooral heterogeneity of farm fields may be a feasible alternative to large-scale revegetation of farmlands for maintaining arthropod biodiversity and their important ecological function. We examined seasonal differences in beetle assemblages in woodland remnants and four adjoining farmland uses in a highly modified agricultural landscape in southeastern Australia. The farmland uses were crops, fallows, and two restoration treatments (fine woody debris applied over harvested crop fields, and restoration plantings). Unexpectedly, overall species richness was significantly lower in remnants than in adjacent farmlands. Remnants and farmlands supported significantly different assemblages, with a third of species found in both habitats. Abundance responses were taxon-specific and influenced by interactions between land use and season. In particular, predator abundance was significantly higher in plantings and fallows during spring compared to summer. Detritivore abundance was significantly higher in the woody debris compared to the adjacent remnants. Herbivore abundance did not differ between remnants and farmlands over time. Complex responses provide strong support for a mosaic of land uses to effectively conserve different beetle groups. Species richness results suggest that further agricultural intensification, in farm fields and through the removal of remnant vegetation, risks reducing beetle diversity in this region. Maintaining farmland heterogeneity with a mix of low-intensity land uses, such as conservation tillage, crop-fallow rotation, restoration plantings, and the novel application of fine woody debris over cultivated fields, may provide seasonal refuge and resources for beetles. © 2017 Ng et al.
- Authors: Ng, Katherina , Driscoll, Don , MacFadyen, Sarina , Barton, Philip , McIntyre, Sue , Lindenmayer, David
- Date: 2017
- Type: Text , Journal article
- Relation: Ecosphere Vol. 8, no. 12 (2017), p.
- Full Text:
- Reviewed:
- Description: There is an urgent need to identify ways of managing agricultural landscapes for biodiversity conservation without reducing food production. Farming practices that consider spatiooral heterogeneity of farm fields may be a feasible alternative to large-scale revegetation of farmlands for maintaining arthropod biodiversity and their important ecological function. We examined seasonal differences in beetle assemblages in woodland remnants and four adjoining farmland uses in a highly modified agricultural landscape in southeastern Australia. The farmland uses were crops, fallows, and two restoration treatments (fine woody debris applied over harvested crop fields, and restoration plantings). Unexpectedly, overall species richness was significantly lower in remnants than in adjacent farmlands. Remnants and farmlands supported significantly different assemblages, with a third of species found in both habitats. Abundance responses were taxon-specific and influenced by interactions between land use and season. In particular, predator abundance was significantly higher in plantings and fallows during spring compared to summer. Detritivore abundance was significantly higher in the woody debris compared to the adjacent remnants. Herbivore abundance did not differ between remnants and farmlands over time. Complex responses provide strong support for a mosaic of land uses to effectively conserve different beetle groups. Species richness results suggest that further agricultural intensification, in farm fields and through the removal of remnant vegetation, risks reducing beetle diversity in this region. Maintaining farmland heterogeneity with a mix of low-intensity land uses, such as conservation tillage, crop-fallow rotation, restoration plantings, and the novel application of fine woody debris over cultivated fields, may provide seasonal refuge and resources for beetles. © 2017 Ng et al.
- Neilan, Wendy, Barton, Philip, McAlpine, Clive, Wood, Jeffrey, Lindenmayer, David
- Authors: Neilan, Wendy , Barton, Philip , McAlpine, Clive , Wood, Jeffrey , Lindenmayer, David
- Date: 2019
- Type: Text , Journal article
- Relation: Ecography Vol. 42, no. 1 (2019), p. 173-186
- Full Text: false
- Reviewed:
- Description: Habitat loss and fragmentation are key processes causing biodiversity loss in human-modified landscapes. Knowledge of these processes has largely been derived from measuring biodiversity at the scale of ‘within-habitat’ fragments with the surrounding landscape considered as matrix. Yet, the loss of variation in species assemblages ‘among’ habitat fragments (landscape-scale) may be as important a driver of biodiversity loss as the loss of diversity ‘within’ habitat fragments (local-scale). We tested the hypothesis that heterogeneity in vegetation cover is important for maintaining alpha and beta diversity in human-modified landscapes. We surveyed bird assemblages in eighty 300-m-long transects nested within twenty 1-km 2 vegetation ‘mosaics’, with mosaics assigned to four categories defined by the cover extent and configuration of native eucalypt forest and exotic pine plantation. We examined bird assemblages at two spatial scales: 1) within and among transects, and 2) within and among mosaics. Alpha diversity was the mean species diversity within-transects or within-mosaics and beta diversity quantified the effective number of compositionally distinct transects or mosaics. We found that within-transect alpha diversity was highest in vegetation mosaics defined by continuous eucalypt forest, lowest in mosaics of continuous pine plantation, and at intermediate levels in mosaics containing eucalypt patches in a pine matrix. We found that eucalypt mosaics had lower beta diversity than other mosaic types when ignoring relative abundances, but had similar or higher beta diversity when weighting with species abundances. Mosaics containing both pine and eucalypt forest differed in their bird compositional variation among transects, despite sharing a similar suite of species. This configuration effect at the mosaic scale reflected differences in vegetation composition among transects. Maintaining heterogeneity in vegetation cover could help to maintain variation among bird assemblages across landscapes, thus partially offsetting local-scale diversity losses due to fragmentation. Critical to this is the retention of remnant native vegetation. © 2018 The Authors
Disentangling the effects of farmland use, habitat edges, and vegetation structure on ground beetle morphological traits
- Ng, Katherina, Barton, Philip, Blanchard, Wade, Evans, Maldwyn, Lindenmayer, David
- Authors: Ng, Katherina , Barton, Philip , Blanchard, Wade , Evans, Maldwyn , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Oecologia Vol. 188, no. 3 (2018), p. 645-657
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- Description: Land-use change due to agriculture has a major influence on arthropod biodiversity, and may influence species differently depending on their traits. It is unclear how species traits vary across different land uses and their edges, with most studies focussing on single habitat types and overlooking edge effects. We examined variation in morphological traits of carabid beetles (Coleoptera:Carabidae) on both sides of edges between woodlands and four adjoining, but contrasting farmland uses in an agricultural landscape. We asked: (1) how do traits differ between woodlands and different adjoining farmland uses (crop, fallow, restoration planting, and woody debris applied over crop), and do effects depend on increasing distances from the farmland–woodland edge? (2) Does vegetation structure explain observed effects of adjoining farmland use and edge effects on these traits? We found that carabid communities varied in body size and shape, including traits associated with diet, robustness, and visual ability. Smaller sized species were associated with woodlands and larger sized species with farmlands. Farmland use further influenced these associations, where woodlands adjoining plantings supported smaller species, while fallows and crops supported larger species. Vegetation structure significantly influenced body size, flying ability, and body shape, and helped explain the effects of farmland use and distance from edges on body size. We highlight the important role of vegetation structure, farmland use, and edge effects in filtering the morphological traits of carabid assemblages across a highly modified agricultural landscape. Our findings suggest that farmland management can influence body size and dispersal-related traits in farmland and adjacent native vegetation. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
- Authors: Ng, Katherina , Barton, Philip , Blanchard, Wade , Evans, Maldwyn , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Oecologia Vol. 188, no. 3 (2018), p. 645-657
- Full Text:
- Reviewed:
- Description: Land-use change due to agriculture has a major influence on arthropod biodiversity, and may influence species differently depending on their traits. It is unclear how species traits vary across different land uses and their edges, with most studies focussing on single habitat types and overlooking edge effects. We examined variation in morphological traits of carabid beetles (Coleoptera:Carabidae) on both sides of edges between woodlands and four adjoining, but contrasting farmland uses in an agricultural landscape. We asked: (1) how do traits differ between woodlands and different adjoining farmland uses (crop, fallow, restoration planting, and woody debris applied over crop), and do effects depend on increasing distances from the farmland–woodland edge? (2) Does vegetation structure explain observed effects of adjoining farmland use and edge effects on these traits? We found that carabid communities varied in body size and shape, including traits associated with diet, robustness, and visual ability. Smaller sized species were associated with woodlands and larger sized species with farmlands. Farmland use further influenced these associations, where woodlands adjoining plantings supported smaller species, while fallows and crops supported larger species. Vegetation structure significantly influenced body size, flying ability, and body shape, and helped explain the effects of farmland use and distance from edges on body size. We highlight the important role of vegetation structure, farmland use, and edge effects in filtering the morphological traits of carabid assemblages across a highly modified agricultural landscape. Our findings suggest that farmland management can influence body size and dispersal-related traits in farmland and adjacent native vegetation. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
Do temporal changes in vegetation structure additional to time since fire predict changes in bird occurrence?
- Lindenmayer, David, Candy, Steven, MacGregor, Christopher, Banks, Sam, Barton, Philip
- Authors: Lindenmayer, David , Candy, Steven , MacGregor, Christopher , Banks, Sam , Barton, Philip
- Date: 2016
- Type: Text , Journal article
- Relation: Ecological Applications Vol. 26, no. 7 (2016), p. 2267-2279
- Full Text:
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- Description: Fire is a major ecological process in ecosystems globally. Its impacts on fauna can be both direct (e.g., mortality) and indirect (e.g., altered habitat), resulting in population recovery being driven by several possible mechanisms. Separating direct from indirect impacts of fire on faunal population recovery can be valuable in guiding management of biodiversity in fire-prone environments. However, resolving the influence of direct and indirect processes remains a key challenge because many processes affecting fauna can change concomitantly with time since fire. We explore the mechanisms influencing bird response to fire by posing the question, can temporal changes in vegetation structure predict changes in bird occurrence on sites, and can these be separated from other temporal changes using the surrogate of time since fire? We conducted a 12-yr study of bird and vegetation responses to fire at 124 sites across six vegetation classes in Booderee National Park, Australia. Approximately half of these sites, established in 2002, were burned by a large (>3000 ha) wildfire in 2003. To disentangle collinear effects of temporal changes in vegetation and direct demographic effects on population recovery that are subsumed by time since fire, we incorporated both longitudinal and cross-sectional vegetation effects in addition to time since fire within logistic structural equation models. We identified temporal changes in vegetation structure and richness of plant and bird species that characterized burned and unburned sites in all vegetation classes. For nine bird species, a significant component of the year trend was driven by temporal trends in one of three vegetation variables (number of understory or midstory plant species, or midstory cover). By contrast, we could not separate temporal effects between time since fire and vegetation attributes for bird species richness, reporting rate, and the occurrence of 11 other bird species. Our findings help identify species for which indirect effects of vegetation dominate recovery and thus may benefit from vegetation management where conservation actions are required and, conversely, those species for which direct effects of time since fire drive recovery, where simply leaving a system to recover following the last disturbance will be sufficient. © 2016 by the Ecological Society of America.
- Authors: Lindenmayer, David , Candy, Steven , MacGregor, Christopher , Banks, Sam , Barton, Philip
- Date: 2016
- Type: Text , Journal article
- Relation: Ecological Applications Vol. 26, no. 7 (2016), p. 2267-2279
- Full Text:
- Reviewed:
- Description: Fire is a major ecological process in ecosystems globally. Its impacts on fauna can be both direct (e.g., mortality) and indirect (e.g., altered habitat), resulting in population recovery being driven by several possible mechanisms. Separating direct from indirect impacts of fire on faunal population recovery can be valuable in guiding management of biodiversity in fire-prone environments. However, resolving the influence of direct and indirect processes remains a key challenge because many processes affecting fauna can change concomitantly with time since fire. We explore the mechanisms influencing bird response to fire by posing the question, can temporal changes in vegetation structure predict changes in bird occurrence on sites, and can these be separated from other temporal changes using the surrogate of time since fire? We conducted a 12-yr study of bird and vegetation responses to fire at 124 sites across six vegetation classes in Booderee National Park, Australia. Approximately half of these sites, established in 2002, were burned by a large (>3000 ha) wildfire in 2003. To disentangle collinear effects of temporal changes in vegetation and direct demographic effects on population recovery that are subsumed by time since fire, we incorporated both longitudinal and cross-sectional vegetation effects in addition to time since fire within logistic structural equation models. We identified temporal changes in vegetation structure and richness of plant and bird species that characterized burned and unburned sites in all vegetation classes. For nine bird species, a significant component of the year trend was driven by temporal trends in one of three vegetation variables (number of understory or midstory plant species, or midstory cover). By contrast, we could not separate temporal effects between time since fire and vegetation attributes for bird species richness, reporting rate, and the occurrence of 11 other bird species. Our findings help identify species for which indirect effects of vegetation dominate recovery and thus may benefit from vegetation management where conservation actions are required and, conversely, those species for which direct effects of time since fire drive recovery, where simply leaving a system to recover following the last disturbance will be sufficient. © 2016 by the Ecological Society of America.
Dynamic effects of ground-layer plant communities on beetles in a fragmented farming landscape
- Ng, Katherina, McIntyre, Sue, Macfadyen, Sarina, Barton, Philip, Driscoll, Don, Lindenmayer, David
- Authors: Ng, Katherina , McIntyre, Sue , Macfadyen, Sarina , Barton, Philip , Driscoll, Don , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Biodiversity and Conservation Vol. 27, no. 9 (2018), p. 2131-2153
- Full Text:
- Reviewed:
- Description: Vegetation effects on arthropods are well recognized, but it is unclear how different vegetation attributes might influence arthropod assemblages across mixed-agricultural landscapes. Understanding how plant communities influence arthropods under different habitat and seasonal contexts can identify vegetation management options for arthropod biodiversity. We examined relationships between vegetation structure, plant species richness and plant species composition, and the diversity and composition of beetles in different habitats and time periods. We asked: (1) What is the relative importance of plant species richness, vegetation structure and plant composition in explaining beetle species richness, activity-density and composition? (2) How do plant-beetle relationships vary between different habitats over time? We sampled beetles using pitfall traps and surveyed vegetation in three habitats (woodland, farmland, their edges) during peak crop growth in spring and post-harvest in summer. Plant composition better predicted beetle composition than vegetation structure. Both plant richness and vegetation structure significantly and positively affected beetle activity-density. The influence of all vegetation attributes often varied in strength and direction between habitats and seasons for all trophic groups. The variable nature of plant-beetle relationships suggests that vegetation management could be targeted at specific habitats and time periods to maximize positive outcomes for beetle diversity. In particular, management that promotes plant richness at edges, and promotes herbaceous cover during summer, can support beetle diversity. Conserving ground cover in all habitats may improve activity-density of all beetle trophic groups. The impacts of existing weed control strategies in Australian crop margins on arthropod biodiversity require further study. © 2018, Springer Science+Business Media B.V., part of Springer Nature.
- Authors: Ng, Katherina , McIntyre, Sue , Macfadyen, Sarina , Barton, Philip , Driscoll, Don , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Biodiversity and Conservation Vol. 27, no. 9 (2018), p. 2131-2153
- Full Text:
- Reviewed:
- Description: Vegetation effects on arthropods are well recognized, but it is unclear how different vegetation attributes might influence arthropod assemblages across mixed-agricultural landscapes. Understanding how plant communities influence arthropods under different habitat and seasonal contexts can identify vegetation management options for arthropod biodiversity. We examined relationships between vegetation structure, plant species richness and plant species composition, and the diversity and composition of beetles in different habitats and time periods. We asked: (1) What is the relative importance of plant species richness, vegetation structure and plant composition in explaining beetle species richness, activity-density and composition? (2) How do plant-beetle relationships vary between different habitats over time? We sampled beetles using pitfall traps and surveyed vegetation in three habitats (woodland, farmland, their edges) during peak crop growth in spring and post-harvest in summer. Plant composition better predicted beetle composition than vegetation structure. Both plant richness and vegetation structure significantly and positively affected beetle activity-density. The influence of all vegetation attributes often varied in strength and direction between habitats and seasons for all trophic groups. The variable nature of plant-beetle relationships suggests that vegetation management could be targeted at specific habitats and time periods to maximize positive outcomes for beetle diversity. In particular, management that promotes plant richness at edges, and promotes herbaceous cover during summer, can support beetle diversity. Conserving ground cover in all habitats may improve activity-density of all beetle trophic groups. The impacts of existing weed control strategies in Australian crop margins on arthropod biodiversity require further study. © 2018, Springer Science+Business Media B.V., part of Springer Nature.
Effects of a large wildfire on vegetation structure in a variable fire mosaic
- Foster, C., Barton, Philip, Robinson, N., MacGregor, C., Lindenmayer, David
- Authors: Foster, C. , Barton, Philip , Robinson, N. , MacGregor, C. , Lindenmayer, David
- Date: 2017
- Type: Text , Journal article
- Relation: Ecological Applications Vol. 27, no. 8 (2017), p. 2369-2381
- Full Text:
- Reviewed:
- Description: Management guidelines for many fire-prone ecosystems highlight the importance of maintaining a variable mosaic of fire histories for biodiversity conservation. Managers are encouraged to aim for fire mosaics that are temporally and spatially dynamic, include all successional states of vegetation, and also include variation in the underlying "invisible mosaic" of past fire frequencies, severities, and fire return intervals. However, establishing and maintaining variable mosaics in contemporary landscapes is subject to many challenges, one of which is deciding how the fire mosaic should be managed following the occurrence of large, unplanned wildfires. A key consideration for this decision is the extent to which the effects of previous fire history on vegetation and habitats persist after major wildfires, but this topic has rarely been investigated empirically. In this study, we tested to what extent a large wildfire interacted with previous fire history to affect the structure of forest, woodland, and heath vegetation in Booderee National Park in southeastern Australia. In 2003, a summer wildfire burned 49.5% of the park, increasing the extent of recently burned vegetation (<10 yr post-fire) to more than 72% of the park area. We tracked the recovery of vegetation structure for nine years following the wildfire and found that the strength and persistence of fire effects differed substantially between vegetation types. Vegetation structure was modified by wildfire in forest, woodland, and heath vegetation, but among-site variability in vegetation structure was reduced only by severe fire in woodland vegetation. There also were persistent legacy effects of the previous fire regime on some attributes of vegetation structure including forest ground and understorey cover, and woodland midstorey and overstorey cover. For example, woodland midstorey cover was greater on sites with higher fire frequency, irrespective of the severity of the 2003 wildfire. Our results show that even after a large, severe wildfire, underlying fire histories can contribute substantially to variation in vegetation structure. This highlights the importance of ensuring that efforts to reinstate variation in vegetation fire age after large wildfires do not inadvertently reduce variation in vegetation structure generated by the underlying invisible mosaic. © 2017 by the Ecological Society of America.
- Authors: Foster, C. , Barton, Philip , Robinson, N. , MacGregor, C. , Lindenmayer, David
- Date: 2017
- Type: Text , Journal article
- Relation: Ecological Applications Vol. 27, no. 8 (2017), p. 2369-2381
- Full Text:
- Reviewed:
- Description: Management guidelines for many fire-prone ecosystems highlight the importance of maintaining a variable mosaic of fire histories for biodiversity conservation. Managers are encouraged to aim for fire mosaics that are temporally and spatially dynamic, include all successional states of vegetation, and also include variation in the underlying "invisible mosaic" of past fire frequencies, severities, and fire return intervals. However, establishing and maintaining variable mosaics in contemporary landscapes is subject to many challenges, one of which is deciding how the fire mosaic should be managed following the occurrence of large, unplanned wildfires. A key consideration for this decision is the extent to which the effects of previous fire history on vegetation and habitats persist after major wildfires, but this topic has rarely been investigated empirically. In this study, we tested to what extent a large wildfire interacted with previous fire history to affect the structure of forest, woodland, and heath vegetation in Booderee National Park in southeastern Australia. In 2003, a summer wildfire burned 49.5% of the park, increasing the extent of recently burned vegetation (<10 yr post-fire) to more than 72% of the park area. We tracked the recovery of vegetation structure for nine years following the wildfire and found that the strength and persistence of fire effects differed substantially between vegetation types. Vegetation structure was modified by wildfire in forest, woodland, and heath vegetation, but among-site variability in vegetation structure was reduced only by severe fire in woodland vegetation. There also were persistent legacy effects of the previous fire regime on some attributes of vegetation structure including forest ground and understorey cover, and woodland midstorey and overstorey cover. For example, woodland midstorey cover was greater on sites with higher fire frequency, irrespective of the severity of the 2003 wildfire. Our results show that even after a large, severe wildfire, underlying fire histories can contribute substantially to variation in vegetation structure. This highlights the importance of ensuring that efforts to reinstate variation in vegetation fire age after large wildfires do not inadvertently reduce variation in vegetation structure generated by the underlying invisible mosaic. © 2017 by the Ecological Society of America.
Effects of environmental variation and livestock grazing on ant community structure in temperate eucalypt woodlands
- Barton, Philip, Sato, Chloe, Kay, Geoffrey, Florance, Daniel, Lindenmayer, David
- Authors: Barton, Philip , Sato, Chloe , Kay, Geoffrey , Florance, Daniel , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Insect Conservation and Diversity Vol. 9, no. 2 (2016), p. 124-134
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- Description: Grazing by livestock is a major ecological disturbance, with potential effects on vegetation, soil, and insect fauna. Ants are a diverse and functionally important insect group with many associations with the ground layer, yet recent global syntheses question the importance of grazing effects on ant communities relative to vegetation or soil. We examined the effects of vegetation, soil and grazing on the whole ant community, ant functional groups, and abundant species in temperate eucalypt woodlands, southeastern Australia. We found limited influence of grazing on our vegetation and soil measures, except for a positive association between grazing and exotic perennial grass cover. We also found that exotic grass cover had a negative effect on overall ant abundance and richness, but not functional groups or individual species. Soil C:N ratio had a positive effect on the subdominant Camponotini, and leaf litter cover had a positive effect on the abundance of cryptic species. Partial Mantel tests revealed an effect of both environmental and grazing measures on ant assemblage composition, but constrained ordination showed that leaf litter cover, grass biomass, and native and exotic perennial grass cover had stronger correlations with ant community structure than grazing. Our study shows that both environmental variation and grazing play a role in driving ant community structure, but that key environmental variables such as grass biomass and leaf litter cover are particularly important in temperate eucalypt woodlands. Monitoring of ant communities to measure the benefits of changed grazing regimes for biodiversity should consider contemporary grazing pressure as well as the underlying effects of variation in plants and soils. © 2016 The Royal Entomological Society.
- Authors: Barton, Philip , Sato, Chloe , Kay, Geoffrey , Florance, Daniel , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Insect Conservation and Diversity Vol. 9, no. 2 (2016), p. 124-134
- Full Text:
- Reviewed:
- Description: Grazing by livestock is a major ecological disturbance, with potential effects on vegetation, soil, and insect fauna. Ants are a diverse and functionally important insect group with many associations with the ground layer, yet recent global syntheses question the importance of grazing effects on ant communities relative to vegetation or soil. We examined the effects of vegetation, soil and grazing on the whole ant community, ant functional groups, and abundant species in temperate eucalypt woodlands, southeastern Australia. We found limited influence of grazing on our vegetation and soil measures, except for a positive association between grazing and exotic perennial grass cover. We also found that exotic grass cover had a negative effect on overall ant abundance and richness, but not functional groups or individual species. Soil C:N ratio had a positive effect on the subdominant Camponotini, and leaf litter cover had a positive effect on the abundance of cryptic species. Partial Mantel tests revealed an effect of both environmental and grazing measures on ant assemblage composition, but constrained ordination showed that leaf litter cover, grass biomass, and native and exotic perennial grass cover had stronger correlations with ant community structure than grazing. Our study shows that both environmental variation and grazing play a role in driving ant community structure, but that key environmental variables such as grass biomass and leaf litter cover are particularly important in temperate eucalypt woodlands. Monitoring of ant communities to measure the benefits of changed grazing regimes for biodiversity should consider contemporary grazing pressure as well as the underlying effects of variation in plants and soils. © 2016 The Royal Entomological Society.
Effects of fire regime on plant species richness and composition differ among forest, woodland and heath vegetation
- Foster, Claire, Barton, Philip, MacGregor, Christopher, Catford, Jane, Blanchard, Wade, Lindenmayer, David
- Authors: Foster, Claire , Barton, Philip , MacGregor, Christopher , Catford, Jane , Blanchard, Wade , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Applied Vegetation Science Vol. 21, no. 1 (2018), p. 132-143
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- Description: Question: Do the effects of fire regimes on plant species richness and composition differ among floristically similar vegetation types?. Location: Booderee National Park, south-eastern Australia. Methods: We completed floristic surveys of 87 sites in Sydney Coastal dry sclerophyll vegetation, where fire history records have been maintained for over 55 years. We tested for associations between different aspects of the recent fire history and plant species richness and composition, and whether these relationships were consistent among structurally defined forest, woodland and heath vegetation types. Results: The relationship between fire regime variables and plant species richness and composition differed among vegetation types, despite the three vegetation types having similar species pools. Fire frequency was positively related to species richness in woodland, negatively related to species richness in heath, and unrelated to species richness in forest. These different relationships were explained by differences in the associations between fire history and species traits among vegetation types. The negative relationship between fire frequency and species richness in heath vegetation was underpinned by reduced occurrence of resprouting species at high fire frequency sites (more than four fires in 55 years). However, in forest and woodland vegetation, resprouting species were not negatively associated with fire frequency. Conclusions: We hypothesize that differing relationships among vegetation types were underpinned by differences in fire behaviour, and/or biotic and abiotic conditions, leading to differences in plant species mortality and post-fire recovery among vegetation types. Our findings suggest that even when there is a high proportion of shared species between vegetation types, fires can have very different effects on vegetation communities, depending on the structural vegetation type. Both research and management of fire regimes may therefore benefit from considering vegetation types as separate management units. © 2017 International Association for Vegetation Science
- Authors: Foster, Claire , Barton, Philip , MacGregor, Christopher , Catford, Jane , Blanchard, Wade , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Applied Vegetation Science Vol. 21, no. 1 (2018), p. 132-143
- Full Text:
- Reviewed:
- Description: Question: Do the effects of fire regimes on plant species richness and composition differ among floristically similar vegetation types?. Location: Booderee National Park, south-eastern Australia. Methods: We completed floristic surveys of 87 sites in Sydney Coastal dry sclerophyll vegetation, where fire history records have been maintained for over 55 years. We tested for associations between different aspects of the recent fire history and plant species richness and composition, and whether these relationships were consistent among structurally defined forest, woodland and heath vegetation types. Results: The relationship between fire regime variables and plant species richness and composition differed among vegetation types, despite the three vegetation types having similar species pools. Fire frequency was positively related to species richness in woodland, negatively related to species richness in heath, and unrelated to species richness in forest. These different relationships were explained by differences in the associations between fire history and species traits among vegetation types. The negative relationship between fire frequency and species richness in heath vegetation was underpinned by reduced occurrence of resprouting species at high fire frequency sites (more than four fires in 55 years). However, in forest and woodland vegetation, resprouting species were not negatively associated with fire frequency. Conclusions: We hypothesize that differing relationships among vegetation types were underpinned by differences in fire behaviour, and/or biotic and abiotic conditions, leading to differences in plant species mortality and post-fire recovery among vegetation types. Our findings suggest that even when there is a high proportion of shared species between vegetation types, fires can have very different effects on vegetation communities, depending on the structural vegetation type. Both research and management of fire regimes may therefore benefit from considering vegetation types as separate management units. © 2017 International Association for Vegetation Science
Evaluating the effectiveness of overstory cover as a surrogate for bird community diversity and population trends
- Pierson, Jennifer, Mortelliti, Alessio, Barton, Philip, Lane, Peter, Lindenmayer, David
- Authors: Pierson, Jennifer , Mortelliti, Alessio , Barton, Philip , Lane, Peter , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Ecological Indicators Vol. 61, no. (2016), p. 790-798
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- Description: Landscape features are often used as surrogates for biodiversity. While landscape features may perform well as surrogates for coarse metrics of biodiversity such as species richness, their value for monitoring population trends in individual species is virtually unexplored. We compared the performance of a proposed habitat surrogate for birds, percentage cover of vegetation overstory, for two distinct aspects of bird assemblages: community diversity (i.e. species richness) and population trends. We used four different long-term studies of open woodland habitats to test the consistency of the relationship between overstory percentage cover and bird species richness across a large spatial extent (>1000 km) in Australia. We then identified twelve bird species with long-term time-series data to test the relationship between change in overstory cover and populations trends. We found percentage cover performed consistently as a surrogate for species richness in three of the four sites. However, there was no clear pattern in the performance of change in percentage cover as a surrogate for population trends. Four bird species exhibited a significant relationship with change in percentage overstory cover in one study, but this was not found across multiple studies. These results demonstrate a lack of consistency in the relationship between change in overstory cover and population trends among bird species, both within and between geographic regions. Our study demonstrates that biodiversity surrogates representing community-level metrics may be consistent across regions, but provide only limited information about individual species population trends. Understanding the limitations of the information provided by a biodiversity surrogate can inform the appropriate context for its application. Crown Copyright © 2015 Published by Elsevier Ltd. All rights reserved.
- Authors: Pierson, Jennifer , Mortelliti, Alessio , Barton, Philip , Lane, Peter , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Ecological Indicators Vol. 61, no. (2016), p. 790-798
- Full Text:
- Reviewed:
- Description: Landscape features are often used as surrogates for biodiversity. While landscape features may perform well as surrogates for coarse metrics of biodiversity such as species richness, their value for monitoring population trends in individual species is virtually unexplored. We compared the performance of a proposed habitat surrogate for birds, percentage cover of vegetation overstory, for two distinct aspects of bird assemblages: community diversity (i.e. species richness) and population trends. We used four different long-term studies of open woodland habitats to test the consistency of the relationship between overstory percentage cover and bird species richness across a large spatial extent (>1000 km) in Australia. We then identified twelve bird species with long-term time-series data to test the relationship between change in overstory cover and populations trends. We found percentage cover performed consistently as a surrogate for species richness in three of the four sites. However, there was no clear pattern in the performance of change in percentage cover as a surrogate for population trends. Four bird species exhibited a significant relationship with change in percentage overstory cover in one study, but this was not found across multiple studies. These results demonstrate a lack of consistency in the relationship between change in overstory cover and population trends among bird species, both within and between geographic regions. Our study demonstrates that biodiversity surrogates representing community-level metrics may be consistent across regions, but provide only limited information about individual species population trends. Understanding the limitations of the information provided by a biodiversity surrogate can inform the appropriate context for its application. Crown Copyright © 2015 Published by Elsevier Ltd. All rights reserved.
Herbivory and fire interact to affect forest understory habitat, but not its use by small vertebrates
- Foster, Claire, Barton, Philip, Sato, C. F., Wood, J. T., Macgregor, C. I., Lindenmayer, David
- Authors: Foster, Claire , Barton, Philip , Sato, C. F. , Wood, J. T. , Macgregor, C. I. , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Animal Conservation Vol. 19, no. 1 (2016), p. 15-25
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- Description: Herbivory and fire are two disturbances that often co-occur, but studies of their interactive effects are rare outside of grassland ecosystems. We experimentally tested the interactive effects of prescribed fire and macropod herbivory on forest understory vegetation and its vertebrate fauna. Fire and herbivory interacted synergistically to affect forest understory vegetation, with palatable plants showing poor post-fire recovery in unfenced sites compared with herbivore exclusion sites. Despite this strong interactive effect on vegetation, small vertebrates responded to the individual, and not the interactive effects of disturbance. The native insectivorous mammal Antechinus stuartii was more frequently encountered on large herbivore exclusion sites, as was the introduced European rabbit. In contrast, the small skink Lampropholis delicata was more common on sites with high densities of large herbivores. Skinks, snakes and European rabbits were also more active on burnt than unburnt sites. Our results suggest that it may be necessary to manage the macropod herbivore population after fire to prevent the decline of palatable plants, and maintain the dense habitat required by some small mammals. However, as the invasive rabbit was most active in macropod-free sites after fire, any management must include control of both types of herbivores. A mix of understory densities may also need to be maintained to ensure the persistence of species preferring more open habitats. Our study demonstrates that interactive effects of disturbance on vegetation communities may not lead to predictable effects on animals, and highlights the importance of considering both multiple stressors, and multiple species, in the management of disturbance regimes. © 2016 The Zoological Society of London.
- Authors: Foster, Claire , Barton, Philip , Sato, C. F. , Wood, J. T. , Macgregor, C. I. , Lindenmayer, David
- Date: 2016
- Type: Text , Journal article
- Relation: Animal Conservation Vol. 19, no. 1 (2016), p. 15-25
- Full Text:
- Reviewed:
- Description: Herbivory and fire are two disturbances that often co-occur, but studies of their interactive effects are rare outside of grassland ecosystems. We experimentally tested the interactive effects of prescribed fire and macropod herbivory on forest understory vegetation and its vertebrate fauna. Fire and herbivory interacted synergistically to affect forest understory vegetation, with palatable plants showing poor post-fire recovery in unfenced sites compared with herbivore exclusion sites. Despite this strong interactive effect on vegetation, small vertebrates responded to the individual, and not the interactive effects of disturbance. The native insectivorous mammal Antechinus stuartii was more frequently encountered on large herbivore exclusion sites, as was the introduced European rabbit. In contrast, the small skink Lampropholis delicata was more common on sites with high densities of large herbivores. Skinks, snakes and European rabbits were also more active on burnt than unburnt sites. Our results suggest that it may be necessary to manage the macropod herbivore population after fire to prevent the decline of palatable plants, and maintain the dense habitat required by some small mammals. However, as the invasive rabbit was most active in macropod-free sites after fire, any management must include control of both types of herbivores. A mix of understory densities may also need to be maintained to ensure the persistence of species preferring more open habitats. Our study demonstrates that interactive effects of disturbance on vegetation communities may not lead to predictable effects on animals, and highlights the importance of considering both multiple stressors, and multiple species, in the management of disturbance regimes. © 2016 The Zoological Society of London.
Integrating theory into disturbance interaction experiments to better inform ecosystem management
- Foster, Claire, Sato, Chloe, Lindenmayer, David, Barton, Philip
- Authors: Foster, Claire , Sato, Chloe , Lindenmayer, David , Barton, Philip
- Date: 2016
- Type: Text , Journal article
- Relation: Global Change Biology Vol. 22, no. 4 (2016), p. 1325-1335
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- Description: Managing multiple, interacting disturbances is a key challenge to biodiversity conservation, and one that will only increase as global change drivers continue to alter disturbance regimes. Theoretical studies have highlighted the importance of a mechanistic understanding of stressor interactions for improving the prediction and management of interactive effects. However, many conservation studies are not designed or interpreted in the context of theory and instead focus on case-specific management questions. This is a problem as it means that few studies test the relationships highlighted in theoretical models as being important for ecological management. We explore the extent of this problem among studies of interacting disturbances by reviewing recent experimental studies of the interaction between fire and grazing in terrestrial ecosystems. Interactions between fire and grazing can occur via a number of pathways; one disturbance can modify the other's likelihood, intensity or spatial distribution, or one disturbance can alter the other's impacts on individual organisms. The strength of such interactions will vary depending on disturbance attributes (e.g. size or intensity), and this variation is likely to be nonlinear. We show that few experiments testing fire-grazing interactions are able to identify the mechanistic pathway driving an observed interaction, and most are unable to detect nonlinear effects. We demonstrate how these limitations compromise the ability of experimental studies to effectively inform ecological management. We propose a series of adjustments to the design of disturbance interaction experiments that would enable tests of key theoretical pathways and provide the deeper ecological understanding necessary for effective management. Such considerations are relevant to studies of a broad range of ecological interactions and are critical to informing the management of disturbance regimes in the context of accelerating global change. © 2016 John Wiley & Sons Ltd.
- Authors: Foster, Claire , Sato, Chloe , Lindenmayer, David , Barton, Philip
- Date: 2016
- Type: Text , Journal article
- Relation: Global Change Biology Vol. 22, no. 4 (2016), p. 1325-1335
- Full Text:
- Reviewed:
- Description: Managing multiple, interacting disturbances is a key challenge to biodiversity conservation, and one that will only increase as global change drivers continue to alter disturbance regimes. Theoretical studies have highlighted the importance of a mechanistic understanding of stressor interactions for improving the prediction and management of interactive effects. However, many conservation studies are not designed or interpreted in the context of theory and instead focus on case-specific management questions. This is a problem as it means that few studies test the relationships highlighted in theoretical models as being important for ecological management. We explore the extent of this problem among studies of interacting disturbances by reviewing recent experimental studies of the interaction between fire and grazing in terrestrial ecosystems. Interactions between fire and grazing can occur via a number of pathways; one disturbance can modify the other's likelihood, intensity or spatial distribution, or one disturbance can alter the other's impacts on individual organisms. The strength of such interactions will vary depending on disturbance attributes (e.g. size or intensity), and this variation is likely to be nonlinear. We show that few experiments testing fire-grazing interactions are able to identify the mechanistic pathway driving an observed interaction, and most are unable to detect nonlinear effects. We demonstrate how these limitations compromise the ability of experimental studies to effectively inform ecological management. We propose a series of adjustments to the design of disturbance interaction experiments that would enable tests of key theoretical pathways and provide the deeper ecological understanding necessary for effective management. Such considerations are relevant to studies of a broad range of ecological interactions and are critical to informing the management of disturbance regimes in the context of accelerating global change. © 2016 John Wiley & Sons Ltd.
Interactive effects of land use, grazing and environment on frogs in an agricultural landscape
- Pulsford, Stephanie, Barton, Philip, Driscoll, Don, Lindenmayer, David
- Authors: Pulsford, Stephanie , Barton, Philip , Driscoll, Don , Lindenmayer, David
- Date: 2019
- Type: Text , Journal article
- Relation: Agriculture, Ecosystems and Environment Vol. 281, no. (2019), p. 25-34
- Full Text: false
- Reviewed:
- Description: Improved management of human-modified landscapes must be part of global efforts to combat biodiversity loss. We aimed to identify which land management types and environmental factors influenced the use of grazing landscapes by frogs. We surveyed frog assemblages in remnant vegetation, four different paddock types (pasture, linear planting, coarse woody debris addition and fence), and two grazing regimes (continuous and rotational). Frogs were surveyed using pitfall and funnel traps in twelve grazing farms in south-eastern Australia. We found that grazed agricultural landscapes provide important habitats for a variety of species of frogs and that frog assemblages were influenced by both farm management type and environmental variables, and their interactions. Total frog abundance increased with proximity to water more strongly in remnants compared to paddocks. This difference in response may be due to different traits and behaviours of frogs in remnants compared to frogs in open paddocks. Rare frog species richness and abundance of a common species (Limnodynastes tasmaniensis) increased with taller ground cover in remnants but no such relationship occurred in paddocks. Different types of predation risk in remnants compared to paddocks may result in greater ground cover shelter requirements in remnants, as vegetation structure can strongly influence predation. Total frog species richness increased more rapidly with higher rainfall in continuously grazed versus rotationally grazed farms. Higher rainfall was associated with taller ground cover. Continuously grazed farms had shorter average ground cover than rotationally grazed farms and the increased ground cover height associated with more rain may bring ground cover to a height better able to provide shelter and reduce desiccation risk for frogs. Our study highlights the importance of both land management practices and environmental conditions and their interaction in shaping frog assemblages. Improved frog biodiversity conservation may be achieved in grazing landscapes by retaining patches of remnant vegetation, maintaining water bodies such as farm dams, and maintaining tall ground cover within vegetation remnants. © 2019 Elsevier B.V.
Long-term bird colonization and turnover in restored woodlands
- Lindenmayer, David, Lane, P., Barton, Philip, Crane, Mason, Ikin, Karen
- Authors: Lindenmayer, David , Lane, P. , Barton, Philip , Crane, Mason , Ikin, Karen
- Date: 2016
- Type: Text , Journal article
- Relation: Biodiversity and Conservation Vol. 25, no. 8 (2016), p. 1587-1603
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- Reviewed:
- Description: The long-term effectiveness of restored areas for biodiversity is poorly known for the majority of restored ecosystems worldwide. We quantified temporal changes in bird occurrence in restoration plantings of different ages and geometries, and compared observed patterns with a reference dataset from woodland remnants on the same farms as our plantings. Over time, bird species richness remained unchanged in spring but exhibited modest increases in winter. We found that wider plantings supported significantly greater bird species richness in spring and winter than narrow plantings. There was no evidence of a significant interaction between planting width and time. We recorded major temporal changes in the occurrence of a range of individual species that indicated a clear turnover of species as plantings matured. Our results further revealed marked differences in individual species occurrence between plantings and woodland remnants. Life-history attributes associated with temporal changes in the bird assemblage were most apparent in winter survey data, and included diet, foraging and nesting patterns, movement behaviour (e.g. migratory vs. dispersive), and body size. Differences in bird assemblages between plantings of different ages suggest that it is important that farms support a range of age classes of planted woodland, if the aim is to maximize the number of native bird species in restored areas. Our data also suggest that changes in the bird species occupying plantings of different ages can be anticipated in a broadly predictable way based on planting geometry (especially width) and key life-history attributes, particularly movement patterns and habitat and diet specialisation. © 2016, Springer Science+Business Media Dordrecht. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
- Authors: Lindenmayer, David , Lane, P. , Barton, Philip , Crane, Mason , Ikin, Karen
- Date: 2016
- Type: Text , Journal article
- Relation: Biodiversity and Conservation Vol. 25, no. 8 (2016), p. 1587-1603
- Full Text:
- Reviewed:
- Description: The long-term effectiveness of restored areas for biodiversity is poorly known for the majority of restored ecosystems worldwide. We quantified temporal changes in bird occurrence in restoration plantings of different ages and geometries, and compared observed patterns with a reference dataset from woodland remnants on the same farms as our plantings. Over time, bird species richness remained unchanged in spring but exhibited modest increases in winter. We found that wider plantings supported significantly greater bird species richness in spring and winter than narrow plantings. There was no evidence of a significant interaction between planting width and time. We recorded major temporal changes in the occurrence of a range of individual species that indicated a clear turnover of species as plantings matured. Our results further revealed marked differences in individual species occurrence between plantings and woodland remnants. Life-history attributes associated with temporal changes in the bird assemblage were most apparent in winter survey data, and included diet, foraging and nesting patterns, movement behaviour (e.g. migratory vs. dispersive), and body size. Differences in bird assemblages between plantings of different ages suggest that it is important that farms support a range of age classes of planted woodland, if the aim is to maximize the number of native bird species in restored areas. Our data also suggest that changes in the bird species occupying plantings of different ages can be anticipated in a broadly predictable way based on planting geometry (especially width) and key life-history attributes, particularly movement patterns and habitat and diet specialisation. © 2016, Springer Science+Business Media Dordrecht. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
Novel bird responses to successive, large-scale, landscape transformations
- Lindenmayer, David, Blanchard, Wade, Westgate, Martin, Foster, Claire, Barton, Philip
- Authors: Lindenmayer, David , Blanchard, Wade , Westgate, Martin , Foster, Claire , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Ecological Monographs Vol. 89, no. 3 (2019), p.
- Full Text:
- Reviewed:
- Description: Transformation of intact vegetation into new kinds and configurations of human-modified habitats is a well-established driver of biodiversity loss. Following initial conversion, many human-dominated landscapes are then subject to further large-scale changes in land use. The impacts on biodiversity of repeated changes in land use remain poorly known, particularly how changes in the matrix interact with initial patterns of vegetation clearing. We used an 18-yr study of birds in remnant patches of endangered temperate woodland in south-eastern Australia to quantify the spatial and temporal effects of successive land use transformation in the surrounding landscape. We examined bird response to (1) initial patterns of landscape modification (creating semi-cleared grazing land dominated by pastures that surrounded remnant woodland patches), (2) subsequent establishment and maturation of exotic tree plantations on the pastures surrounding woodland patches, and (3) additive and interactive effects of both types of landscape transformation. The majority of the 57 bird species modeled responded to conversion of grazing land to exotic plantations, either independently from initial patterns of landscape transformation (20 species), or interactively (18 species) or additively (15 species) with initial landscape transformation. The occurrence of only one species (the Common Bronzewing) was related to patterns of initial transformation but not subsequent transformation due to plantation establishment. Thus, despite many characteristics of the woodland patches within the plantation remaining largely unaltered throughout our 18-yr investigation, the matrix had a profound effect on the kinds of species inhabiting them, with such impacts often magnified over time as the matrix continued to change. Plantation establishment triggered new regional-level spatial processes with effects on birds detected in woodland patches up to 2 km away from the plantation. Matrix conversion selected for species with different traits (size, diet and movement patterns) compared to the initial transformation, suggesting it is acting as a different filter on the bird community. New kinds of landscape transformation (such as plantation establishment on previously cleared land) can radically affect the species that have persisted for many decades in previously modified landscapes. This highlights the challenges, but also opportunities, for conserving taxa in ever changing human-dominated environments. © 2019 by the Ecological Society of America. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
- Authors: Lindenmayer, David , Blanchard, Wade , Westgate, Martin , Foster, Claire , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Ecological Monographs Vol. 89, no. 3 (2019), p.
- Full Text:
- Reviewed:
- Description: Transformation of intact vegetation into new kinds and configurations of human-modified habitats is a well-established driver of biodiversity loss. Following initial conversion, many human-dominated landscapes are then subject to further large-scale changes in land use. The impacts on biodiversity of repeated changes in land use remain poorly known, particularly how changes in the matrix interact with initial patterns of vegetation clearing. We used an 18-yr study of birds in remnant patches of endangered temperate woodland in south-eastern Australia to quantify the spatial and temporal effects of successive land use transformation in the surrounding landscape. We examined bird response to (1) initial patterns of landscape modification (creating semi-cleared grazing land dominated by pastures that surrounded remnant woodland patches), (2) subsequent establishment and maturation of exotic tree plantations on the pastures surrounding woodland patches, and (3) additive and interactive effects of both types of landscape transformation. The majority of the 57 bird species modeled responded to conversion of grazing land to exotic plantations, either independently from initial patterns of landscape transformation (20 species), or interactively (18 species) or additively (15 species) with initial landscape transformation. The occurrence of only one species (the Common Bronzewing) was related to patterns of initial transformation but not subsequent transformation due to plantation establishment. Thus, despite many characteristics of the woodland patches within the plantation remaining largely unaltered throughout our 18-yr investigation, the matrix had a profound effect on the kinds of species inhabiting them, with such impacts often magnified over time as the matrix continued to change. Plantation establishment triggered new regional-level spatial processes with effects on birds detected in woodland patches up to 2 km away from the plantation. Matrix conversion selected for species with different traits (size, diet and movement patterns) compared to the initial transformation, suggesting it is acting as a different filter on the bird community. New kinds of landscape transformation (such as plantation establishment on previously cleared land) can radically affect the species that have persisted for many decades in previously modified landscapes. This highlights the challenges, but also opportunities, for conserving taxa in ever changing human-dominated environments. © 2019 by the Ecological Society of America. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
Optimal taxonomic groups for biodiversity assessment: a meta-analytic approach
- Westgate, Martin, Tulloch, Ayesha, Barton, Philip, Pierson, Jennifer, Lindenmayer, David
- Authors: Westgate, Martin , Tulloch, Ayesha , Barton, Philip , Pierson, Jennifer , Lindenmayer, David
- Date: 2017
- Type: Text , Journal article
- Relation: Ecography Vol. 40, no. 4 (2017), p. 539-548
- Full Text:
- Reviewed:
- Description: A fundamental decision in biodiversity assessment is the selection of one or more study taxa, a choice that is often made using qualitative criteria such as historical precedent, ease of detection, or available technical or taxonomic expertise. A more robust approach would involve selecting taxa based on the a priori expectation that they will provide the best possible information on unmeasured groups, but data to inform such hypotheses are often lacking. Using a global meta-analysis, we quantified the proportion of variability that each of 12 taxonomic groups (at the Order level or above) explained in the richness or composition of other taxa. We then applied optimization to matrices of pairwise congruency to identify the best set of complementary surrogate groups. We found that no single taxon was an optimal surrogate for both the richness and composition of unmeasured taxa if we used simple methods to aggregate congruence data between studies. In contrast, statistical methods that accounted for well-known drivers of cross-taxon congruence (spatial extent, grain size, and latitude) lead to the prioritization of similar surrogates for both species richness and composition. Advanced statistical methods were also more effective at describing known ecological relationships between taxa than simple methods, and show that congruence is typically highest between taxonomically and functionally dissimilar taxa. Birds and vascular plants were most frequently selected by our algorithm as surrogates for other taxonomic groups, but the extent to which any one taxon was the ‘optimal’ choice of surrogate for other biodiversity was highly context-dependent. In the absence of other information – such as in data-poor areas of the globe, and under limited budgets for monitoring or assessment – ecologists can use our results to assess which taxa are most likely to reflect the distribution of the richness or composition of ‘total’ biodiversity. © 2016 The Authors
- Authors: Westgate, Martin , Tulloch, Ayesha , Barton, Philip , Pierson, Jennifer , Lindenmayer, David
- Date: 2017
- Type: Text , Journal article
- Relation: Ecography Vol. 40, no. 4 (2017), p. 539-548
- Full Text:
- Reviewed:
- Description: A fundamental decision in biodiversity assessment is the selection of one or more study taxa, a choice that is often made using qualitative criteria such as historical precedent, ease of detection, or available technical or taxonomic expertise. A more robust approach would involve selecting taxa based on the a priori expectation that they will provide the best possible information on unmeasured groups, but data to inform such hypotheses are often lacking. Using a global meta-analysis, we quantified the proportion of variability that each of 12 taxonomic groups (at the Order level or above) explained in the richness or composition of other taxa. We then applied optimization to matrices of pairwise congruency to identify the best set of complementary surrogate groups. We found that no single taxon was an optimal surrogate for both the richness and composition of unmeasured taxa if we used simple methods to aggregate congruence data between studies. In contrast, statistical methods that accounted for well-known drivers of cross-taxon congruence (spatial extent, grain size, and latitude) lead to the prioritization of similar surrogates for both species richness and composition. Advanced statistical methods were also more effective at describing known ecological relationships between taxa than simple methods, and show that congruence is typically highest between taxonomically and functionally dissimilar taxa. Birds and vascular plants were most frequently selected by our algorithm as surrogates for other taxonomic groups, but the extent to which any one taxon was the ‘optimal’ choice of surrogate for other biodiversity was highly context-dependent. In the absence of other information – such as in data-poor areas of the globe, and under limited budgets for monitoring or assessment – ecologists can use our results to assess which taxa are most likely to reflect the distribution of the richness or composition of ‘total’ biodiversity. © 2016 The Authors
Population genetic analysis reveals a long-term decline of a threatened endemic Australian marsupial
- Hansen, Birgita, Harley, Daniel, Lindenmayer, David, Taylor, Andrea
- Authors: Hansen, Birgita , Harley, Daniel , Lindenmayer, David , Taylor, Andrea
- Date: 2009
- Type: Text , Journal article
- Relation: Molecular Ecology Vol. 18, no. 16 (2009), p. 3346-3362
- Full Text: false
- Reviewed:
- Description: Since European colonization, Leadbeater's possum (Gymnobelideus leadbeateri) has declined across its range to the point where it is now only patchily distributed within the montane ash forests of the Central Highlands of Victoria. The loss of large hollow-bearing trees coupled with inadequate recruitment of mature ash forest has been predicted to result in a reduction in population size of up to 90% by 2020. Furthermore, bioclimatic analyses have suggested additional reductions in the species' distribution under a variety of climate change scenarios. Using a panel of 15 highly resolving microsatellite markers and mitochondrial control region sequence data, we infer past and present gene flow. Populations in the northern part of the core range were highly admixed, and showed no signs of either current or historical barriers to gene flow. A marginal, isolated and inbred population at Yellingbo was highly genetically differentiated, both in terms of current and historic genetic structure. Sequence data confirmed the conclusions from earlier genetic simulation studies that the Yellingbo population has been isolated from the rest of the species range since before European-induced changes to the montane landscape, and formed part of a larger genetic unit that is now otherwise extinct. Historic loss of maternal lineages in the Central Highlands of Victoria was detected despite signals of immigration, indicating population declines that most probably coincided with changes in climate at the end of the Pleistocene. Given ongoing habitat loss and the recent (February 2009) wildfire in the Central Highlands, we forecast (potentially extensive) demographic declines, in line with predicted range reductions under climate change scenarios. © 2009 Blackwell Publishing Ltd.