Outfoxing the fox : effect of prey odor on fox behavior in a pastoral landscape
- Andrewartha, Tim, Evans, Maldwyn, Batson, William, Manning, Adrian, Barton, Philip
- Authors: Andrewartha, Tim , Evans, Maldwyn , Batson, William , Manning, Adrian , Barton, Philip
- Date: 2021
- Type: Text , Journal article
- Relation: Conservation Science and Practice Vol. 3, no. 12 (2021), p.
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- Description: Invasive mammalian predators have had a devastating effect on native species globally. The European red fox (Vulpes vulpes) is one such species where it has been introduced in Australia. A novel but unexplored tactic to reduce the impact of mammalian predators is the use of unrewarded prey odors to undermine the effectiveness of olfactory hunting behavior. To test the viability of unrewarded prey odors in an applied setting we investigated how foxes responded to the odors of three different prey species. We used the odors of two locally extinct native Australian marsupials; the eastern quoll (a smaller carnivore) and eastern bettong (a fungivore), and the European rabbit, an introduced herbivore. Conducting our research over a period of 3 weeks in a pastoral environment in South-eastern Australia, we used video observations of foxes' behaviors, as they encountered the different odors. We found a reduction in the number of fox visits to bettong odors in the third week. In contrast, we observed a sustained number of visits to rabbit odors. Foxes also spent more time investigating rabbit odors and displayed longer durations of vigilance behavior at quoll odors. Our results support the hypothesis that the exposure of wild foxes to unrewarded odors of novel prey species can reduce their interest in these odors, which might translate to a reduction in predation pressure. Our results also suggest, however, that olfactory pre-exposure may not be as effective at reducing fox interest in a competitor species' odor. © 2021 The Authors. Conservation Science and Practice published by Wiley Periodicals LLC. on behalf of Society for Conservation Biology
- Authors: Andrewartha, Tim , Evans, Maldwyn , Batson, William , Manning, Adrian , Barton, Philip
- Date: 2021
- Type: Text , Journal article
- Relation: Conservation Science and Practice Vol. 3, no. 12 (2021), p.
- Full Text:
- Reviewed:
- Description: Invasive mammalian predators have had a devastating effect on native species globally. The European red fox (Vulpes vulpes) is one such species where it has been introduced in Australia. A novel but unexplored tactic to reduce the impact of mammalian predators is the use of unrewarded prey odors to undermine the effectiveness of olfactory hunting behavior. To test the viability of unrewarded prey odors in an applied setting we investigated how foxes responded to the odors of three different prey species. We used the odors of two locally extinct native Australian marsupials; the eastern quoll (a smaller carnivore) and eastern bettong (a fungivore), and the European rabbit, an introduced herbivore. Conducting our research over a period of 3 weeks in a pastoral environment in South-eastern Australia, we used video observations of foxes' behaviors, as they encountered the different odors. We found a reduction in the number of fox visits to bettong odors in the third week. In contrast, we observed a sustained number of visits to rabbit odors. Foxes also spent more time investigating rabbit odors and displayed longer durations of vigilance behavior at quoll odors. Our results support the hypothesis that the exposure of wild foxes to unrewarded odors of novel prey species can reduce their interest in these odors, which might translate to a reduction in predation pressure. Our results also suggest, however, that olfactory pre-exposure may not be as effective at reducing fox interest in a competitor species' odor. © 2021 The Authors. Conservation Science and Practice published by Wiley Periodicals LLC. on behalf of Society for Conservation Biology
Soil chemical markers distinguishing human and pig decomposition islands : a preliminary study
- Barton, Philip, Reboldi, Anna, Dawson, Blake, Ueland, Maiken, Strong, Craig, Wallman, James
- Authors: Barton, Philip , Reboldi, Anna , Dawson, Blake , Ueland, Maiken , Strong, Craig , Wallman, James
- Date: 2020
- Type: Text , Journal article
- Relation: Forensic Science, Medicine, and Pathology Vol. 16, no. 4 (2020), p. 605-612
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- Description: The decomposition of vertebrate cadavers on the soil surface produces nutrient-rich fluids that enter the soil profile, leaving clear evidence of the presence of a cadaver decomposition island. Few studies, however, have described soil physicochemistry under human cadavers, or compared the soil between human and non-human animal models. In this study, we sampled soil to 5 cm depth at distances of 0 cm and 30 cm from cadavers, as well as from control sites 90 cm distant, from five human and three pig cadavers at the Australian Facility for Taphonomic Experimental Research (AFTER). We found that soil moisture, electrical conductivity, nitrate, ammonium, and total phosphorus were higher in soil directly under cadavers (0 cm), with very limited lateral spread beyond 30 cm. These patterns lasted up to 700 days, indicating that key soil nutrients might be useful markers of the location of the decomposition island for up to 2 years. Soil phosphorus was always higher under pigs than humans, suggesting a possible difference in the decomposition and soil processes under these two cadaver types. Our preliminary study highlights the need for further experimental and replicated research to quantify variability in soil properties, and to identify when non-human animals are suitable analogues. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.
- Authors: Barton, Philip , Reboldi, Anna , Dawson, Blake , Ueland, Maiken , Strong, Craig , Wallman, James
- Date: 2020
- Type: Text , Journal article
- Relation: Forensic Science, Medicine, and Pathology Vol. 16, no. 4 (2020), p. 605-612
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- Description: The decomposition of vertebrate cadavers on the soil surface produces nutrient-rich fluids that enter the soil profile, leaving clear evidence of the presence of a cadaver decomposition island. Few studies, however, have described soil physicochemistry under human cadavers, or compared the soil between human and non-human animal models. In this study, we sampled soil to 5 cm depth at distances of 0 cm and 30 cm from cadavers, as well as from control sites 90 cm distant, from five human and three pig cadavers at the Australian Facility for Taphonomic Experimental Research (AFTER). We found that soil moisture, electrical conductivity, nitrate, ammonium, and total phosphorus were higher in soil directly under cadavers (0 cm), with very limited lateral spread beyond 30 cm. These patterns lasted up to 700 days, indicating that key soil nutrients might be useful markers of the location of the decomposition island for up to 2 years. Soil phosphorus was always higher under pigs than humans, suggesting a possible difference in the decomposition and soil processes under these two cadaver types. Our preliminary study highlights the need for further experimental and replicated research to quantify variability in soil properties, and to identify when non-human animals are suitable analogues. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.
Towards quantifying carrion biomass in ecosystems
- Barton, Philip, Evans, Maldwyn, Foster, Claire, Pechal, Jennifer, Bump, Joseph
- Authors: Barton, Philip , Evans, Maldwyn , Foster, Claire , Pechal, Jennifer , Bump, Joseph
- Date: 2019
- Type: Text , Journal article , Review
- Relation: Trends in Ecology and Evolution Vol. 34, no. 10 (2019), p. 950-961
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- Description: The decomposition of animal biomass (carrion) contributes to the recycling of energy and nutrients through ecosystems. Whereas the role of plant decomposition in ecosystems is broadly recognised, the significance of carrion to ecosystem functioning remains poorly understood. Quantitative data on carrion biomass are lacking and there is no clear pathway towards improved knowledge in this area. Here, we present a framework to show how quantities derived from individual carcasses can be scaled up using population metrics, allowing for comparisons among ecosystems and other forms of biomass. Our framework facilitates the generation of new data that is critical to building a quantitative understanding of the contribution of carrion to trophic processes and ecosystem stocks and flows. © 2019 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: Barton, Philip , Evans, Maldwyn , Foster, Claire , Pechal, Jennifer , Bump, Joseph
- Date: 2019
- Type: Text , Journal article , Review
- Relation: Trends in Ecology and Evolution Vol. 34, no. 10 (2019), p. 950-961
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- Description: The decomposition of animal biomass (carrion) contributes to the recycling of energy and nutrients through ecosystems. Whereas the role of plant decomposition in ecosystems is broadly recognised, the significance of carrion to ecosystem functioning remains poorly understood. Quantitative data on carrion biomass are lacking and there is no clear pathway towards improved knowledge in this area. Here, we present a framework to show how quantities derived from individual carcasses can be scaled up using population metrics, allowing for comparisons among ecosystems and other forms of biomass. Our framework facilitates the generation of new data that is critical to building a quantitative understanding of the contribution of carrion to trophic processes and ecosystem stocks and flows. © 2019 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**
Higher-taxon and functional group responses of ant and bird assemblages to livestock grazing : a test of an explicit surrogate concept
- Barton, Philip, Evans, Maldwyn, Sato, Chloe, O'Loughlin, Luke, Foster, Claire
- Authors: Barton, Philip , Evans, Maldwyn , Sato, Chloe , O'Loughlin, Luke , Foster, Claire
- Date: 2019
- Type: Text , Journal article
- Relation: Ecological Indicators Vol. 96, no. (2019), p. 458-465
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- Description: Biodiversity monitoring programs are routinely established to quantify changes in biotic communities in response to land management. Surrogacy is implicitly used in many such monitoring programs whereby the measurement of a component of biodiversity is used to infer responses of broader biodiversity. Yet rarely is this surrogacy validated by demonstrating that measured variables and the target variable of interest have matching responses to management treatments. Here we examined the responses of higher-taxon and functional groupings of ants and birds (our surrogate variables) two years after the implementation of experimental livestock grazing treatments, and compared these with the responses of total ant and bird species richness (our target variables) to the same treatments. We found significant and strong correlations between surrogate and target variables, but this did not predict corresponding similar response to treatments. For ants, we found that the genus Monomorium had a negative response to the grazing exclusion treatment, but there was no matching response of species richness, and so no surrogacy was identified. For birds, total species richness had a weak positive response to spring/summer grazing exclusion, and the abundance of honeyeaters (Meliphagidae) showed a similar positive response, suggesting surrogacy. Our study highlights that correlations among variables do not necessarily lead to surrogacy, and indeed that different sub-components of biotic assemblages can respond in ways that contrast with overall species richness. Careful assessment of the matched responses of surrogate and target variables to management can provide a simple and robust way to critically assess biodiversity surrogacy. © 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: Barton, Philip , Evans, Maldwyn , Sato, Chloe , O'Loughlin, Luke , Foster, Claire
- Date: 2019
- Type: Text , Journal article
- Relation: Ecological Indicators Vol. 96, no. (2019), p. 458-465
- Full Text:
- Reviewed:
- Description: Biodiversity monitoring programs are routinely established to quantify changes in biotic communities in response to land management. Surrogacy is implicitly used in many such monitoring programs whereby the measurement of a component of biodiversity is used to infer responses of broader biodiversity. Yet rarely is this surrogacy validated by demonstrating that measured variables and the target variable of interest have matching responses to management treatments. Here we examined the responses of higher-taxon and functional groupings of ants and birds (our surrogate variables) two years after the implementation of experimental livestock grazing treatments, and compared these with the responses of total ant and bird species richness (our target variables) to the same treatments. We found significant and strong correlations between surrogate and target variables, but this did not predict corresponding similar response to treatments. For ants, we found that the genus Monomorium had a negative response to the grazing exclusion treatment, but there was no matching response of species richness, and so no surrogacy was identified. For birds, total species richness had a weak positive response to spring/summer grazing exclusion, and the abundance of honeyeaters (Meliphagidae) showed a similar positive response, suggesting surrogacy. Our study highlights that correlations among variables do not necessarily lead to surrogacy, and indeed that different sub-components of biotic assemblages can respond in ways that contrast with overall species richness. Careful assessment of the matched responses of surrogate and target variables to management can provide a simple and robust way to critically assess biodiversity surrogacy. © 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**
Substantial long-term effects of carcass addition on soil and plants in a grassy eucalypt woodland
- Barton, Philip, McIntyre, Sue, Evans, Maldwyn, Bump, Joseph, Cunningham, Saul, Manning, Adrian
- Authors: Barton, Philip , McIntyre, Sue , Evans, Maldwyn , Bump, Joseph , Cunningham, Saul , Manning, Adrian
- Date: 2016
- Type: Text , Journal article
- Relation: Ecosphere Vol. 7, no. 10 (2016), p.
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- Description: The decomposition of large vertebrate carcasses generates small-scale disturbances characterized by changes in soil chemistry and new opportunities for plant establishment. Yet few studies have examined whether this effect is still evident several years after death, or has consequences for landscape-scale heterogeneity. We examined soil chemistry and plant species richness and composition at 12 kangaroo carcasses (~30 kg initial mass) five years after their initial placement. Each carcass was paired with a nearby "control" site for comparison. We found that soil phosphorus was eight times higher at carcasses than at control sites, but that nitrogen concentration was similar. We also found that plant composition was substantially different between each carcass and control pair, with 80% of carcasses dominated by exotic species (mostly weedy annuals). Notably, overall variability in plant species composition across carcass sites was not different from the variability at control sites, indicating that the colonization of carcasses by weedy species did not have a homogenizing effect on plant assemblages across our study landscape. Our study demonstrates that a localized effect of large vertebrate carcasses on soil and plants was still evident after five years, indicating a state shift in the soil-plant dynamics at a carcass site. However, the effect of carcasses on landscape-scale plant community heterogeneity was minimal because colonization was by weedy plants already present in the landscape. © 2016 Barton et al.
- Authors: Barton, Philip , McIntyre, Sue , Evans, Maldwyn , Bump, Joseph , Cunningham, Saul , Manning, Adrian
- Date: 2016
- Type: Text , Journal article
- Relation: Ecosphere Vol. 7, no. 10 (2016), p.
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- Description: The decomposition of large vertebrate carcasses generates small-scale disturbances characterized by changes in soil chemistry and new opportunities for plant establishment. Yet few studies have examined whether this effect is still evident several years after death, or has consequences for landscape-scale heterogeneity. We examined soil chemistry and plant species richness and composition at 12 kangaroo carcasses (~30 kg initial mass) five years after their initial placement. Each carcass was paired with a nearby "control" site for comparison. We found that soil phosphorus was eight times higher at carcasses than at control sites, but that nitrogen concentration was similar. We also found that plant composition was substantially different between each carcass and control pair, with 80% of carcasses dominated by exotic species (mostly weedy annuals). Notably, overall variability in plant species composition across carcass sites was not different from the variability at control sites, indicating that the colonization of carcasses by weedy species did not have a homogenizing effect on plant assemblages across our study landscape. Our study demonstrates that a localized effect of large vertebrate carcasses on soil and plants was still evident after five years, indicating a state shift in the soil-plant dynamics at a carcass site. However, the effect of carcasses on landscape-scale plant community heterogeneity was minimal because colonization was by weedy plants already present in the landscape. © 2016 Barton et al.
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:
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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.
Insect biodiversity meets ecosystem function : differential effects of habitat and insects on carrion decomposition
- Barton, Philip, Evans, Maldwyn
- Authors: Barton, Philip , Evans, Maldwyn
- Date: 2017
- Type: Text , Journal article
- Relation: Ecological Entomology Vol. 42, no. 3 (2017), p. 364-374
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- Description: 1. Ecological processes are maintained in different environments by different species performing similar functional roles. Yet, little is known about the role of the environment in shaping insect biodiversity associated with a process that is ephemeral and patchy. 2. In this study, the mass loss of carrion in response to contrasting habitat types (grassland or tree) was quantified experimentally, as well as the presence, diversity and composition of insect assemblages. Differences in insect assemblages between these two habitats were also examined. 3. It was found that the presence of insects led to a doubling in mass loss, but that grassland or tree habitat type had no effect on this process. By contrast, habitat type had a significant effect on the composition of generalist ant and beetle assemblages, but not on specialist fly assemblages. Given the colonisation of insects, carrion mass loss was negatively associated with increasing evenness of fly assemblages and increasing ant abundance. Variation in fly assemblage composition was also found to correlate with variation in carrion mass loss. 4. This study highlights the major role of habitat type in shaping the composition of generalist insects at carrion, but the minor role in affecting specialist and highly vagile insects. This complements the authors' findings that insect colonisation of carrion was critical to accelerated mass loss, and that fly assemblages were responsible for variation in this process, regardless of habitat. The present study sheds new light on the contribution of insect biodiversity to decomposition in variable environments, with consequences for carrion food webs and nutrient cycling. © 2017 The Royal Entomological Society
- Authors: Barton, Philip , Evans, Maldwyn
- Date: 2017
- Type: Text , Journal article
- Relation: Ecological Entomology Vol. 42, no. 3 (2017), p. 364-374
- Full Text:
- Reviewed:
- Description: 1. Ecological processes are maintained in different environments by different species performing similar functional roles. Yet, little is known about the role of the environment in shaping insect biodiversity associated with a process that is ephemeral and patchy. 2. In this study, the mass loss of carrion in response to contrasting habitat types (grassland or tree) was quantified experimentally, as well as the presence, diversity and composition of insect assemblages. Differences in insect assemblages between these two habitats were also examined. 3. It was found that the presence of insects led to a doubling in mass loss, but that grassland or tree habitat type had no effect on this process. By contrast, habitat type had a significant effect on the composition of generalist ant and beetle assemblages, but not on specialist fly assemblages. Given the colonisation of insects, carrion mass loss was negatively associated with increasing evenness of fly assemblages and increasing ant abundance. Variation in fly assemblage composition was also found to correlate with variation in carrion mass loss. 4. This study highlights the major role of habitat type in shaping the composition of generalist insects at carrion, but the minor role in affecting specialist and highly vagile insects. This complements the authors' findings that insect colonisation of carrion was critical to accelerated mass loss, and that fly assemblages were responsible for variation in this process, regardless of habitat. The present study sheds new light on the contribution of insect biodiversity to decomposition in variable environments, with consequences for carrion food webs and nutrient cycling. © 2017 The Royal Entomological Society
Environmental and spatial drivers of spider diversity at contrasting microhabitats
- Barton, Philip, Evans, Maldwyn, Foster, Claire, Cunningham, Saul, Manning, Adrian
- Authors: Barton, Philip , Evans, Maldwyn , Foster, Claire , Cunningham, Saul , Manning, Adrian
- Date: 2017
- Type: Text , Journal article
- Relation: Austral Ecology Vol. 42, no. 6 (2017), p. 700-710
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- Description: The relative importance of environmental and spatial drivers of animal diversity varies across scales, but identifying these scales can be difficult if a sampling design does not match the scale of the target organisms' interaction with their habitat. In this study, we quantify and compare the effects of environmental variation and spatial proximity on ground-dwelling spider assemblages sampled from three distinct microhabitat types (open grassland, logs, trees) that recur across structurally heterogeneous grassy woodlands. We used model selection and multivariate procedures to compare the effects of different environmental attributes and spatial proximity on spider assemblages at each microhabitat type. We found that species richness and assemblage composition differed among microhabitat types. Bare ground cover had a negative effect on spider richness under trees, but a positive effect on spider richness in open grassland. Turnover in spider assemblages from open grassland was correlated with environmental distance, but not geographic distance. By contrast, turnover in spiders at logs and trees was correlated with geographic distance, but not environmental distance. Our study suggests that spider assemblages from widespread and connected open grassland habitat were more affected by environmental than spatial gradients, whereas spiders at log and tree habitats were more affected by spatial distance among these discrete but recurring microhabitats. Deliberate selection and sampling of small-scale habitat features can provide robust information about the drivers of arthropod diversity and turnover in landscapes. © 2017 Ecological Society of Australia
- Authors: Barton, Philip , Evans, Maldwyn , Foster, Claire , Cunningham, Saul , Manning, Adrian
- Date: 2017
- Type: Text , Journal article
- Relation: Austral Ecology Vol. 42, no. 6 (2017), p. 700-710
- Full Text:
- Reviewed:
- Description: The relative importance of environmental and spatial drivers of animal diversity varies across scales, but identifying these scales can be difficult if a sampling design does not match the scale of the target organisms' interaction with their habitat. In this study, we quantify and compare the effects of environmental variation and spatial proximity on ground-dwelling spider assemblages sampled from three distinct microhabitat types (open grassland, logs, trees) that recur across structurally heterogeneous grassy woodlands. We used model selection and multivariate procedures to compare the effects of different environmental attributes and spatial proximity on spider assemblages at each microhabitat type. We found that species richness and assemblage composition differed among microhabitat types. Bare ground cover had a negative effect on spider richness under trees, but a positive effect on spider richness in open grassland. Turnover in spider assemblages from open grassland was correlated with environmental distance, but not geographic distance. By contrast, turnover in spiders at logs and trees was correlated with geographic distance, but not environmental distance. Our study suggests that spider assemblages from widespread and connected open grassland habitat were more affected by environmental than spatial gradients, whereas spiders at log and tree habitats were more affected by spatial distance among these discrete but recurring microhabitats. Deliberate selection and sampling of small-scale habitat features can provide robust information about the drivers of arthropod diversity and turnover in landscapes. © 2017 Ecological Society of Australia
Temperature dynamics in different body regions of decomposing vertebrate remains
- Barton, Philip, Dawson, Blake, Barton, Andrew, Joshua, Sergio, Wallman, James
- Authors: Barton, Philip , Dawson, Blake , Barton, Andrew , Joshua, Sergio , Wallman, James
- Date: 2021
- Type: Text , Journal article
- Relation: Forensic Science International Vol. 325, no. (2021), p.
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- Description: The decomposition of vertebrates is controlled largely by external temperature, yet internal temperatures can also play an important role but are generally poorly documented. In this study, we compared continuous hourly temperature recordings from the mouth, under the head, right chest and right abdomen, and in the rectum of one refrigerated human and one fresh pig cadaver during 29 days of decomposition. Each cadaver differed in its internal starting temperature, thus providing two contrasting case studies for examining temperature dynamics among body regions. We used time-series analysis methods common to hydrology to reveal key differences in internal temperature dynamics. Within both cadavers, the chest region experienced the highest average temperatures, and the mouth experienced the highest maximum hourly temperature. Temperatures exceeded 30 °C inside the pig for between 40% (rectum) and 75% (chest) of the duration of the study, but for only 20% (rectum) and 35% (chest) of the time in the human. Our study provides evidence of the different thermal trajectories occurring in different body regions, and some similarities between two cadavers despite their different starting thermal conditions. These results improve our understanding of why decomposition occurs at different rates within the same cadaver, and that the location of blowfly larvae collections should be noted to improve estimates of the post-mortem interval. © 2021 Elsevier B.V.
- Authors: Barton, Philip , Dawson, Blake , Barton, Andrew , Joshua, Sergio , Wallman, James
- Date: 2021
- Type: Text , Journal article
- Relation: Forensic Science International Vol. 325, no. (2021), p.
- Full Text:
- Reviewed:
- Description: The decomposition of vertebrates is controlled largely by external temperature, yet internal temperatures can also play an important role but are generally poorly documented. In this study, we compared continuous hourly temperature recordings from the mouth, under the head, right chest and right abdomen, and in the rectum of one refrigerated human and one fresh pig cadaver during 29 days of decomposition. Each cadaver differed in its internal starting temperature, thus providing two contrasting case studies for examining temperature dynamics among body regions. We used time-series analysis methods common to hydrology to reveal key differences in internal temperature dynamics. Within both cadavers, the chest region experienced the highest average temperatures, and the mouth experienced the highest maximum hourly temperature. Temperatures exceeded 30 °C inside the pig for between 40% (rectum) and 75% (chest) of the duration of the study, but for only 20% (rectum) and 35% (chest) of the time in the human. Our study provides evidence of the different thermal trajectories occurring in different body regions, and some similarities between two cadavers despite their different starting thermal conditions. These results improve our understanding of why decomposition occurs at different rates within the same cadaver, and that the location of blowfly larvae collections should be noted to improve estimates of the post-mortem interval. © 2021 Elsevier B.V.
Necrobiome framework for bridging decomposition ecology of autotrophically and heterotrophically derived organic matter
- Benbow, M., Barton, Philip, Ulyshen, Michael, Beasley, James, DeVault, Travis
- Authors: Benbow, M. , Barton, Philip , Ulyshen, Michael , Beasley, James , DeVault, Travis
- Date: 2019
- Type: Text , Journal article
- Relation: Ecological Monographs Vol. 89, no. 1 (2019), p.
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- Description: Decomposition contributes to global ecosystem function by contributing to nutrient recycling, energy flow, and limiting biomass accumulation. The decomposer organisms influencing this process form diverse, complex, and highly dynamic communities that often specialize on different plant or animal resources. Despite performing the same net role, there is a need to conceptually synthesize information on the structure and function of decomposer communities across the spectrum of dead plant and animal resources. A lack of synthesis has limited cross-disciplinary learning and research in important areas of ecosystem and community ecology. Here we expound on the “necrobiome” concept and develop a framework describing the decomposer communities and their interactions associated with plant and animal resource types within multiple ecosystems. We outline the biotic structure and ecological functions of the necrobiome, along with how the necrobiome fits into a broader landscape and ecosystem context. The expanded necrobiome model provides a set of perspectives on decomposer communities across resource types, and conceptually unifies plant and animal decomposer communities into the same framework, while acknowledging key differences in processes and mechanisms. This framework is intended to raise awareness among researchers, and advance the construction of explicit, mechanistic hypotheses that further our understanding of decomposer community contributions to biodiversity, the structure and function of ecosystems, global nutrient recycling and energy flow. © 2018 by the Ecological Society of America
- Authors: Benbow, M. , Barton, Philip , Ulyshen, Michael , Beasley, James , DeVault, Travis
- Date: 2019
- Type: Text , Journal article
- Relation: Ecological Monographs Vol. 89, no. 1 (2019), p.
- Full Text:
- Reviewed:
- Description: Decomposition contributes to global ecosystem function by contributing to nutrient recycling, energy flow, and limiting biomass accumulation. The decomposer organisms influencing this process form diverse, complex, and highly dynamic communities that often specialize on different plant or animal resources. Despite performing the same net role, there is a need to conceptually synthesize information on the structure and function of decomposer communities across the spectrum of dead plant and animal resources. A lack of synthesis has limited cross-disciplinary learning and research in important areas of ecosystem and community ecology. Here we expound on the “necrobiome” concept and develop a framework describing the decomposer communities and their interactions associated with plant and animal resource types within multiple ecosystems. We outline the biotic structure and ecological functions of the necrobiome, along with how the necrobiome fits into a broader landscape and ecosystem context. The expanded necrobiome model provides a set of perspectives on decomposer communities across resource types, and conceptually unifies plant and animal decomposer communities into the same framework, while acknowledging key differences in processes and mechanisms. This framework is intended to raise awareness among researchers, and advance the construction of explicit, mechanistic hypotheses that further our understanding of decomposer community contributions to biodiversity, the structure and function of ecosystems, global nutrient recycling and energy flow. © 2018 by the Ecological Society of America
The ephemeral resource patch concept
- Butterworth, Nathan, Benbow, M., Barton, Philip
- Authors: Butterworth, Nathan , Benbow, M. , Barton, Philip
- Date: 2023
- Type: Text , Journal article
- Relation: Biological Reviews Vol. 98, no. 3 (2023), p. 697-726
- Full Text:
- Reviewed:
- Description: Ephemeral resource patches (ERPs) – short lived resources including dung, carrion, temporary pools, rotting vegetation, decaying wood, and fungi – are found throughout every ecosystem. Their short-lived dynamics greatly enhance ecosystem heterogeneity and have shaped the evolutionary trajectories of a wide range of organisms – from bacteria to insects and amphibians. Despite this, there has been no attempt to distinguish ERPs clearly from other resource types, to identify their shared spatiotemporal characteristics, or to articulate their broad ecological and evolutionary influences on biotic communities. Here, we define ERPs as any distinct consumable resources which (i) are homogeneous (genetically, chemically, or structurally) relative to the surrounding matrix, (ii) host a discrete multitrophic community consisting of species that cannot replicate solely in any of the surrounding matrix, and (iii) cannot maintain a balance between depletion and renewal, which in turn, prevents multiple generations of consumers/users or reaching a community equilibrium. We outline the wide range of ERPs that fit these criteria, propose 12 spatiotemporal characteristics along which ERPs can vary, and synthesise a large body of literature that relates ERP dynamics to ecological and evolutionary theory. We draw this knowledge together and present a new unifying conceptual framework that incorporates how ERPs have shaped the adaptive trajectories of organisms, the structure of ecosystems, and how they can be integrated into biodiversity management and conservation. Future research should focus on how inter- and intra-resource variation occurs in nature – with a particular focus on resource × environment × genotype interactions. This will likely reveal novel adaptive strategies, aid the development of new eco-evolutionary theory, and greatly improve our understanding of the form and function of organisms and ecosystems. © 2022 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.
- Authors: Butterworth, Nathan , Benbow, M. , Barton, Philip
- Date: 2023
- Type: Text , Journal article
- Relation: Biological Reviews Vol. 98, no. 3 (2023), p. 697-726
- Full Text:
- Reviewed:
- Description: Ephemeral resource patches (ERPs) – short lived resources including dung, carrion, temporary pools, rotting vegetation, decaying wood, and fungi – are found throughout every ecosystem. Their short-lived dynamics greatly enhance ecosystem heterogeneity and have shaped the evolutionary trajectories of a wide range of organisms – from bacteria to insects and amphibians. Despite this, there has been no attempt to distinguish ERPs clearly from other resource types, to identify their shared spatiotemporal characteristics, or to articulate their broad ecological and evolutionary influences on biotic communities. Here, we define ERPs as any distinct consumable resources which (i) are homogeneous (genetically, chemically, or structurally) relative to the surrounding matrix, (ii) host a discrete multitrophic community consisting of species that cannot replicate solely in any of the surrounding matrix, and (iii) cannot maintain a balance between depletion and renewal, which in turn, prevents multiple generations of consumers/users or reaching a community equilibrium. We outline the wide range of ERPs that fit these criteria, propose 12 spatiotemporal characteristics along which ERPs can vary, and synthesise a large body of literature that relates ERP dynamics to ecological and evolutionary theory. We draw this knowledge together and present a new unifying conceptual framework that incorporates how ERPs have shaped the adaptive trajectories of organisms, the structure of ecosystems, and how they can be integrated into biodiversity management and conservation. Future research should focus on how inter- and intra-resource variation occurs in nature – with a particular focus on resource × environment × genotype interactions. This will likely reveal novel adaptive strategies, aid the development of new eco-evolutionary theory, and greatly improve our understanding of the form and function of organisms and ecosystems. © 2022 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.
Priority effects and density promote coexistence between the facultative predator Chrysomya rufifacies and its competitor Calliphora stygia
- Dawson, Blake, Wallman, James, Evans, Maldwyn, Butterworth, Nathan, Barton, Philip
- Authors: Dawson, Blake , Wallman, James , Evans, Maldwyn , Butterworth, Nathan , Barton, Philip
- Date: 2022
- Type: Text , Journal article
- Relation: Oecologia Vol. 199, no. 1 (2022), p. 181-191
- Full Text:
- Reviewed:
- Description: Highly competitive ephemeral resources like carrion tend to support much greater diversity relative to longer-lived resources. The coexistence of diverse communities on short-lived carrion is a delicate balance, maintained by several processes including competition. Despite this balance, few studies have investigated the effect of competition on carrion, limiting our understanding of how competition drives coexistence. We investigated how priority effects and larval density influence coexistence between two blowfly species, the facultative predator Chrysomya rufifacies and its competitor Calliphora stygia, which occupy broadly similar niches but differ in their ecological strategies for exploiting carrion. We examined how adult oviposition, larval survival, developmental duration, and adult fitness were affected by the presence of differently aged heterospecific larval masses, and how these measures varied under three larval densities. We found C. rufifacies larval survival was lowest in conspecific masses with low larval densities. In heterospecific masses, survival increased, particularly at high larval density, with priority effects having minimal effect, suggesting a dependency on collective exodigestion. For C. stygia, we found survival to be constant across larval densities in a conspecific mass. In heterospecific masses, survival decreased drastically when C. rufifacies arrived first, regardless of larval density, suggesting C. stygia is temporally constrained to avoid competition with C. rufifacies. Neither species appeared to completely outcompete the other, as they were either constrained by density requirements (C. rufifacies) or priority effects (C. stygia). Our results provide new mechanistic insights into the ecological processes allowing for coexistence on a competitively intense, ephemeral resource such as carrion. © 2022, The Author(s).
- Authors: Dawson, Blake , Wallman, James , Evans, Maldwyn , Butterworth, Nathan , Barton, Philip
- Date: 2022
- Type: Text , Journal article
- Relation: Oecologia Vol. 199, no. 1 (2022), p. 181-191
- Full Text:
- Reviewed:
- Description: Highly competitive ephemeral resources like carrion tend to support much greater diversity relative to longer-lived resources. The coexistence of diverse communities on short-lived carrion is a delicate balance, maintained by several processes including competition. Despite this balance, few studies have investigated the effect of competition on carrion, limiting our understanding of how competition drives coexistence. We investigated how priority effects and larval density influence coexistence between two blowfly species, the facultative predator Chrysomya rufifacies and its competitor Calliphora stygia, which occupy broadly similar niches but differ in their ecological strategies for exploiting carrion. We examined how adult oviposition, larval survival, developmental duration, and adult fitness were affected by the presence of differently aged heterospecific larval masses, and how these measures varied under three larval densities. We found C. rufifacies larval survival was lowest in conspecific masses with low larval densities. In heterospecific masses, survival increased, particularly at high larval density, with priority effects having minimal effect, suggesting a dependency on collective exodigestion. For C. stygia, we found survival to be constant across larval densities in a conspecific mass. In heterospecific masses, survival decreased drastically when C. rufifacies arrived first, regardless of larval density, suggesting C. stygia is temporally constrained to avoid competition with C. rufifacies. Neither species appeared to completely outcompete the other, as they were either constrained by density requirements (C. rufifacies) or priority effects (C. stygia). Our results provide new mechanistic insights into the ecological processes allowing for coexistence on a competitively intense, ephemeral resource such as carrion. © 2022, The Author(s).
Insect abundance patterns on vertebrate remains reveal carrion resource quality variation
- Dawson, Blake, Wallman, James, Evans, Maldwyn, Barton, Philip
- Authors: Dawson, Blake , Wallman, James , Evans, Maldwyn , Barton, Philip
- Date: 2022
- Type: Text , Journal article
- Relation: Oecologia Vol. 198, no. 4 (2022), p. 1043-1056
- Full Text:
- Reviewed:
- Description: Resource quality is a key driver of species abundance and community structure. Carrion is unique among resources due to its high nutritional quality, rapidly changing nature, and the diverse community of organisms it supports. Yet the role resource quality plays in driving variation in abundance patterns of carrion-associated species remains poorly studied. Here we investigate how species abundances change with a measure of resource change, and interpret these findings to determine how species differ in their association with carrion that changes in quality over time. We conducted field succession experiments using pigs and humans over two winters and one summer. We quantified the effect of total body score, an objective measure of resource change, on adult insect abundance using generalised additive models. For each species, phases of increasing abundance likely indicated attraction to a high-quality resource, and length of abundance maxima indicated optimal oviposition and feeding time. Some species such as the beetle Necrobia rufipes had a rapid spike in abundance, suggesting a narrow window of opportunity for carrion resource exploitation, while species like the wasp Nasonia vitripennis had a gradual change in abundance, indicating a wide window of resource exploitation. Different abundance patterns were also observed between species occurring on pigs and humans, suggesting cadaver type is an important aspect of resource quality. Our findings show that species abundances, unlike species occurrences, can reveal additional detail about species exploitation of carrion and provide information about how resource quality may drive competition and variation in insect community succession. © 2022, The Author(s).
- Authors: Dawson, Blake , Wallman, James , Evans, Maldwyn , Barton, Philip
- Date: 2022
- Type: Text , Journal article
- Relation: Oecologia Vol. 198, no. 4 (2022), p. 1043-1056
- Full Text:
- Reviewed:
- Description: Resource quality is a key driver of species abundance and community structure. Carrion is unique among resources due to its high nutritional quality, rapidly changing nature, and the diverse community of organisms it supports. Yet the role resource quality plays in driving variation in abundance patterns of carrion-associated species remains poorly studied. Here we investigate how species abundances change with a measure of resource change, and interpret these findings to determine how species differ in their association with carrion that changes in quality over time. We conducted field succession experiments using pigs and humans over two winters and one summer. We quantified the effect of total body score, an objective measure of resource change, on adult insect abundance using generalised additive models. For each species, phases of increasing abundance likely indicated attraction to a high-quality resource, and length of abundance maxima indicated optimal oviposition and feeding time. Some species such as the beetle Necrobia rufipes had a rapid spike in abundance, suggesting a narrow window of opportunity for carrion resource exploitation, while species like the wasp Nasonia vitripennis had a gradual change in abundance, indicating a wide window of resource exploitation. Different abundance patterns were also observed between species occurring on pigs and humans, suggesting cadaver type is an important aspect of resource quality. Our findings show that species abundances, unlike species occurrences, can reveal additional detail about species exploitation of carrion and provide information about how resource quality may drive competition and variation in insect community succession. © 2022, The Author(s).
How does mass loss compare with total body score when assessing decomposition of human and pig cadavers?
- Dawson, Blake, Wallman, James, Barton, Philip
- Authors: Dawson, Blake , Wallman, James , Barton, Philip
- Date: 2022
- Type: Text , Journal article
- Relation: Forensic Science, Medicine, and Pathology Vol. 18, no. 3 (2022), p. 343-351
- Full Text:
- Reviewed:
- Description: Providing accurate and reliable measures of decomposition is paramount for forensic research where decomposition progress is used to estimate time of death. Mass loss is routinely used as a direct measure of biomass decomposition in ecological studies, yet few studies have analysed mass loss in a forensic context on human cadavers to determine its usefulness for modelling the decomposition process. Mass loss was examined in decomposing human and pig cadavers, and compared with other common decomposition metrics, such as total body score (TBS). One summer and one winter field decomposition experiment was conducted using human and pig cadavers, as pigs are often used as proxies for human cadavers in forensic research. The two measures of decomposition revealed two contrasting patterns of decomposition on pigs and humans, particularly in winter where TBS stabilised at similar values, but mass loss differed greatly. Mass loss was found to be faster in pigs than humans during early decomposition. Pigs lost 75% of their mass in winter, while humans lost less than 50%; however, in summer, both lost around 80% of their mass. TBS displayed similar patterns in both experiments, with TBS increasing more rapidly in pigs compared with humans but both eventually reaching similar TBS values in late decomposition. Measuring mass loss can provide additional information about decomposition progress that is missed if using TBS only. Key differences in decomposition progress between cadaver types were also observed, suggesting caution when extrapolating data from pigs to humans for forensic research and decomposition modelling. © 2022, The Author(s).
- Authors: Dawson, Blake , Wallman, James , Barton, Philip
- Date: 2022
- Type: Text , Journal article
- Relation: Forensic Science, Medicine, and Pathology Vol. 18, no. 3 (2022), p. 343-351
- Full Text:
- Reviewed:
- Description: Providing accurate and reliable measures of decomposition is paramount for forensic research where decomposition progress is used to estimate time of death. Mass loss is routinely used as a direct measure of biomass decomposition in ecological studies, yet few studies have analysed mass loss in a forensic context on human cadavers to determine its usefulness for modelling the decomposition process. Mass loss was examined in decomposing human and pig cadavers, and compared with other common decomposition metrics, such as total body score (TBS). One summer and one winter field decomposition experiment was conducted using human and pig cadavers, as pigs are often used as proxies for human cadavers in forensic research. The two measures of decomposition revealed two contrasting patterns of decomposition on pigs and humans, particularly in winter where TBS stabilised at similar values, but mass loss differed greatly. Mass loss was found to be faster in pigs than humans during early decomposition. Pigs lost 75% of their mass in winter, while humans lost less than 50%; however, in summer, both lost around 80% of their mass. TBS displayed similar patterns in both experiments, with TBS increasing more rapidly in pigs compared with humans but both eventually reaching similar TBS values in late decomposition. Measuring mass loss can provide additional information about decomposition progress that is missed if using TBS only. Key differences in decomposition progress between cadaver types were also observed, suggesting caution when extrapolating data from pigs to humans for forensic research and decomposition modelling. © 2022, The Author(s).
A long-term habitat fragmentation experiment leads to morphological change in a species of carabid beetle
- Evans, Maldwyn, Banks, Sam, Barton, Philip, Davies, Kendi, Driscoll, Don
- Authors: Evans, Maldwyn , Banks, Sam , Barton, Philip , Davies, Kendi , Driscoll, Don
- Date: 2018
- Type: Text , Journal article
- Relation: Ecological Entomology Vol. 43, no. 3 (2018), p. 282-293
- Full Text:
- Reviewed:
- Description: 1. Habitat fragmentation and transformation are key drivers of species declines in landscapes. Most of the current understanding of species' responses to environmental change originates from studies of populations and communities. However, phenotypic variation offers another key aspect of species responses and could provide additional insights into the functional drivers of population change. 2. The goal of this study was to address this gap by exploring the morphological changes of a species of carabid beetle (Notonomus resplendens) with a known population response to the Wog Wog Habitat Fragmentation Experiment in Australia. We measured morphological traits associated with body size, head width, and dispersal ability. We quantified patterns of morphological variation over time and between native Eucalyptus forest fragments and the surrounding pine plantation matrix and the continuous intact native Eucalyptus forest controls. 3. We found sexually dimorphic morphological changes in response to the experimental treatments. Males increased in size, had larger legs and had smaller interocular widths in the matrix in both the short and long terms. Conversely, females became comparatively smaller and had increased interocular widths in the same treatments. Effects in the fragments were similar to those in the matrix, but exhibited more uncertainty. 4. Our results demonstrate that species can show morphological change in response to environmental change over very short time periods. We demonstrate that using both population and morphological data allows stronger inferences about the mechanisms behind species responses to environmental change. © 2017 The Royal Entomological Society
- Authors: Evans, Maldwyn , Banks, Sam , Barton, Philip , Davies, Kendi , Driscoll, Don
- Date: 2018
- Type: Text , Journal article
- Relation: Ecological Entomology Vol. 43, no. 3 (2018), p. 282-293
- Full Text:
- Reviewed:
- Description: 1. Habitat fragmentation and transformation are key drivers of species declines in landscapes. Most of the current understanding of species' responses to environmental change originates from studies of populations and communities. However, phenotypic variation offers another key aspect of species responses and could provide additional insights into the functional drivers of population change. 2. The goal of this study was to address this gap by exploring the morphological changes of a species of carabid beetle (Notonomus resplendens) with a known population response to the Wog Wog Habitat Fragmentation Experiment in Australia. We measured morphological traits associated with body size, head width, and dispersal ability. We quantified patterns of morphological variation over time and between native Eucalyptus forest fragments and the surrounding pine plantation matrix and the continuous intact native Eucalyptus forest controls. 3. We found sexually dimorphic morphological changes in response to the experimental treatments. Males increased in size, had larger legs and had smaller interocular widths in the matrix in both the short and long terms. Conversely, females became comparatively smaller and had increased interocular widths in the same treatments. Effects in the fragments were similar to those in the matrix, but exhibited more uncertainty. 4. Our results demonstrate that species can show morphological change in response to environmental change over very short time periods. We demonstrate that using both population and morphological data allows stronger inferences about the mechanisms behind species responses to environmental change. © 2017 The Royal Entomological Society
Ecological processes associated with different animal taxa in urban environments
- Evans, Maldwyn, Barton, Philip, Westgate, Martin, Soga, Masashi, Fujita, Go, Miyashita, Tadashi
- Authors: Evans, Maldwyn , Barton, Philip , Westgate, Martin , Soga, Masashi , Fujita, Go , Miyashita, Tadashi
- Date: 2021
- Type: Text , Journal article
- Relation: Ecosphere Vol. 12, no. 8 (2021), p.
- Full Text:
- Reviewed:
- Description: Urbanization is increasing globally with wide-ranging consequences for biodiversity and the ecological processes it performs. Yet knowledge of the range of ecological processes supported by biodiversity in urban environments, and the different taxa that perform these processes is poorly understood. We used a text-analysis approach to identify the research trends and gaps in knowledge in the literature on ecological processes provided by animals in urban environments. We found a divide in urban ecological processes research that grouped studies into those with an explicit link to ecological processes and those that focused on biodiversity and made an implicit link to ecological processes. We also found that the dominant taxa in urban ecological processes research were insects, which has more than twice as many studies as birds or mammals, potentially due to their recognized and explicit link to key processes and services (e.g., pollination, pollution biomonitoring) and disservices (e.g., pests, disease transmission). We found a further split between terrestrial and aquatic studies, with urban aquatic studies also declining in relative prevalence over the last 20 yr. To consolidate and advance research on ecological processes in urban environments, we suggest it will be important to bridge the divide between studies on explicit services and others on more general biodiversity. This might be achieved by placing greater focus on the processes provided by non-insect taxa, and by integrating aquatic and terrestrial perspectives. © 2021 The Authors.
- Authors: Evans, Maldwyn , Barton, Philip , Westgate, Martin , Soga, Masashi , Fujita, Go , Miyashita, Tadashi
- Date: 2021
- Type: Text , Journal article
- Relation: Ecosphere Vol. 12, no. 8 (2021), p.
- Full Text:
- Reviewed:
- Description: Urbanization is increasing globally with wide-ranging consequences for biodiversity and the ecological processes it performs. Yet knowledge of the range of ecological processes supported by biodiversity in urban environments, and the different taxa that perform these processes is poorly understood. We used a text-analysis approach to identify the research trends and gaps in knowledge in the literature on ecological processes provided by animals in urban environments. We found a divide in urban ecological processes research that grouped studies into those with an explicit link to ecological processes and those that focused on biodiversity and made an implicit link to ecological processes. We also found that the dominant taxa in urban ecological processes research were insects, which has more than twice as many studies as birds or mammals, potentially due to their recognized and explicit link to key processes and services (e.g., pollination, pollution biomonitoring) and disservices (e.g., pests, disease transmission). We found a further split between terrestrial and aquatic studies, with urban aquatic studies also declining in relative prevalence over the last 20 yr. To consolidate and advance research on ecological processes in urban environments, we suggest it will be important to bridge the divide between studies on explicit services and others on more general biodiversity. This might be achieved by placing greater focus on the processes provided by non-insect taxa, and by integrating aquatic and terrestrial perspectives. © 2021 The Authors.
Traits reveal ecological strategies driving carrion insect community assembly
- Evans, Maldwyn, Wallman, James, Barton, Philip
- Authors: Evans, Maldwyn , Wallman, James , Barton, Philip
- Date: 2020
- Type: Text , Journal article
- Relation: Ecological Entomology Vol. 45, no. 5 (2020), p. 966-977
- Full Text:
- Reviewed:
- Description: 1. The succession of carrion-associated (necrophilous) insects on decomposing carrion is well documented. To exploit the changing nutritious and dynamic resources available throughout the carrion decomposition process, different species colonise and consume carrion in a predictable temporal sequence. The traits of these necrophilous insects should reflect their ecological strategies. Morphological traits of these insects, such as body size and wing size, however, have not previously been examined during active and advanced decomposition. 2. We used fourth-corner multivariate generalised linear models to identify insect community morphological trait patterns and to quantify their change through time on decomposing rabbit carcasses in grassland and woodland environments. 3. We found that larger-bodied species of flies and carrion-specialist beetles were associated with the early stages of decomposition. The morphological traits of ants, in contrast, showed no changes at carcasses through time and instead showed body size differences between grassland and woodland environments. 4. Our findings indicate that specialist flies and beetles that arrive early in the decomposition process possess traits that enable rapid discovery of carrion at a large scale. Generalist beetles and ants do not share this same trait and are instead adapted to locate and consume a wider variety of resources in their preferred habitat type at their local scale. 5. Our results provide insights into the morphological adaptations linked to the ecological strategies of distinct components of carrion insect communities. Further, our results offer insights into the community assembly dynamics that structure the communities of necrophilous insect species. © 2020 The Royal Entomological Society
- Authors: Evans, Maldwyn , Wallman, James , Barton, Philip
- Date: 2020
- Type: Text , Journal article
- Relation: Ecological Entomology Vol. 45, no. 5 (2020), p. 966-977
- Full Text:
- Reviewed:
- Description: 1. The succession of carrion-associated (necrophilous) insects on decomposing carrion is well documented. To exploit the changing nutritious and dynamic resources available throughout the carrion decomposition process, different species colonise and consume carrion in a predictable temporal sequence. The traits of these necrophilous insects should reflect their ecological strategies. Morphological traits of these insects, such as body size and wing size, however, have not previously been examined during active and advanced decomposition. 2. We used fourth-corner multivariate generalised linear models to identify insect community morphological trait patterns and to quantify their change through time on decomposing rabbit carcasses in grassland and woodland environments. 3. We found that larger-bodied species of flies and carrion-specialist beetles were associated with the early stages of decomposition. The morphological traits of ants, in contrast, showed no changes at carcasses through time and instead showed body size differences between grassland and woodland environments. 4. Our findings indicate that specialist flies and beetles that arrive early in the decomposition process possess traits that enable rapid discovery of carrion at a large scale. Generalist beetles and ants do not share this same trait and are instead adapted to locate and consume a wider variety of resources in their preferred habitat type at their local scale. 5. Our results provide insights into the morphological adaptations linked to the ecological strategies of distinct components of carrion insect communities. Further, our results offer insights into the community assembly dynamics that structure the communities of necrophilous insect species. © 2020 The Royal Entomological Society
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.
How practitioners integrate decision triggers with existing metrics in conservation monitoring
- Foster, Claire, O'Loughlin, Luke, Sato, Chloe, Westgate, Martin, Barton, Philip
- Authors: Foster, Claire , O'Loughlin, Luke , Sato, Chloe , Westgate, Martin , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Journal of Environmental Management Vol. 230, no. (2019), p. 94-101
- Full Text:
- Reviewed:
- Description: Decision triggers are defined thresholds in the status of monitored variables that indicate when to undertake management, and avoid undesirable ecosystem change. Decision triggers are frequently recommended to conservation practitioners as a tool to facilitate evidence-based management practices, but there has been limited attention paid to how practitioners are integrating decision triggers into existing monitoring programs. We sought to understand whether conservation practitioners’ use of decision triggers was influenced by the type of variables in their monitoring programs. We investigated this question using a practitioner-focused workshop involving a structured discussion and review of eight monitoring programs. Among our case studies, direct measures of biodiversity (e.g. native species) were more commonly monitored, but less likely to be linked to decision triggers (10% with triggers) than measures being used as surrogates (54% with triggers) for program objectives. This was because decision triggers were associated with management of threatening processes, which were often monitored as a surrogate for a biodiversity asset of interest. By contrast, direct measures of biodiversity were more commonly associated with informal decision processes that led to activities such as management reviews or external consultation. Workshop participants were in favor of including more formalized decision triggers in their programs, but were limited by incomplete ecological knowledge, lack of appropriately skilled staff, funding constraints, and/or uncertainty regarding intervention effectiveness. We recommend that practitioners consider including decision triggers for discussion activities (such as external consultation) in their programs as more than just early warning points for future interventions, particularly for direct measures. Decision triggers for discussions should be recognized as a critical feature of monitoring programs where information and operational limitations inhibit the use of decision triggers for interventions. © 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: Foster, Claire , O'Loughlin, Luke , Sato, Chloe , Westgate, Martin , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Journal of Environmental Management Vol. 230, no. (2019), p. 94-101
- Full Text:
- Reviewed:
- Description: Decision triggers are defined thresholds in the status of monitored variables that indicate when to undertake management, and avoid undesirable ecosystem change. Decision triggers are frequently recommended to conservation practitioners as a tool to facilitate evidence-based management practices, but there has been limited attention paid to how practitioners are integrating decision triggers into existing monitoring programs. We sought to understand whether conservation practitioners’ use of decision triggers was influenced by the type of variables in their monitoring programs. We investigated this question using a practitioner-focused workshop involving a structured discussion and review of eight monitoring programs. Among our case studies, direct measures of biodiversity (e.g. native species) were more commonly monitored, but less likely to be linked to decision triggers (10% with triggers) than measures being used as surrogates (54% with triggers) for program objectives. This was because decision triggers were associated with management of threatening processes, which were often monitored as a surrogate for a biodiversity asset of interest. By contrast, direct measures of biodiversity were more commonly associated with informal decision processes that led to activities such as management reviews or external consultation. Workshop participants were in favor of including more formalized decision triggers in their programs, but were limited by incomplete ecological knowledge, lack of appropriately skilled staff, funding constraints, and/or uncertainty regarding intervention effectiveness. We recommend that practitioners consider including decision triggers for discussion activities (such as external consultation) in their programs as more than just early warning points for future interventions, particularly for direct measures. Decision triggers for discussions should be recognized as a critical feature of monitoring programs where information and operational limitations inhibit the use of decision triggers for interventions. © 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**
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
- 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
- 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