Limited understanding of bushfire impacts on Australian invertebrates
- Authors: Saunders, Manu , Barton, Philip , Bickerstaff, James , Frost, Lindsey , Umbers, Kate
- Date: 2021
- Type: Text , Journal article
- Relation: Insect Conservation and Diversity Vol. 14, no. 3 (2021), p. 285-293
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- Description: Understanding how increasing risk of frequent and severe fires affects biodiversity and ecosystem function is important for effective conservation and recovery, but large knowledge gaps exist for many taxa in many parts of the world, especially invertebrates. After Australia's 2019–2020 catastrophic bushfire disaster, estimates of biodiversity loss and government priorities for post-fire conservation activities were focused on vertebrates and plants because of lack of knowledge about invertebrates. Our synthesis of published evidence reveals a fragmented and ambiguous body of literature on invertebrate responses to fire in Australian ecosystems, limiting the capacity of evidence to inform effective conservation policy in response to extreme fire events. Peer-reviewed studies are available for only six of the more than 30 invertebrate phyla and 88% were on arthropods, predominantly ants. Nearly all studies (94%) were conducted in terrestrial habitats, with only four studies measuring impacts in freshwater habitats and no studies of impacts on marine invertebrates. The high variation in study designs and treatment categories, as well as the absence of key methodological details in many older observational studies, means that there is substantial opportunity to improve our approach to collating meaningful estimates of general fire effects. To understand the full ecological effects of catastrophic fire events, and design effective policies that support recovery of ecosystems now and in future, it is critical that we improve understanding of how fire regimes affect invertebrates. We list key priorities for research and policy to support invertebrate conservation and ecosystem recovery in the face of increasing fire risk. © 2021 Royal Entomological Society. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Kate Umbers” is provided in this record**
Contrasting insect activity and decomposition of pigs and humans in an Australian environment : a preliminary study
- Authors: Dawson, Blake , Barton, Philip , Wallman, James
- Date: 2020
- Type: Text , Journal article
- Relation: Forensic Science International Vol. 316, no. (2020), p.
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- Description: Non-human vertebrate animals, primarily domestic pigs, have been widely used in forensic science research as analogues for humans due to ethical and logistical constraints. Yet the suitability of pigs to mimic human decomposition and entomological patterns remains largely untested, and explicit comparative research in this area is lacking. We compared the decomposition rates and insect communities found at pig and human remains during summer and winter at the Australian Facility for Taphonomic Experimental Research (AFTER). Pigs decomposed faster than humans, with pigs entering active decay earlier in both summer and winter, and humans undergoing desiccation rather than skeletonisation. There was also a delay in the colonisation of humans by both flies and beetles. Species richness of these necrophagous taxa was between two and five times higher during the first two weeks of decomposition on pigs compared to humans during both summer and winter. Insect species composition was also significantly different between pigs and humans in each season. We interpret our findings to mean that the difference between humans and pigs, such as their mass, diet, medical history, or their microbiomes, might be causing different decomposition processes and altered timing or production of chemical cues for insect colonisation. Although preliminary, our results suggest that pigs might not be accurate substitutes for humans in particular fields of taphonomy and forensic entomology. Our findings also have broader implications for the reliability of forensic studies using pigs as models for humans, and highlight the need to recognise intrinsic differences between animal models and humans. © 2020 Elsevier B.V.
- Description: This work was supported in part by the Australian Research Council ( LE150100015 ), as well as by a SMAH Small Project Grant ( University of Wollongong ).
Monitoring the dead as an ecosystem indicator
- Authors: Newsome, Thomas , Barton, Brandon , Buck, Julia , DeBruyn, Jennifer , Barton, Philip
- Date: 2021
- Type: Text , Journal article
- Relation: Ecology and Evolution Vol. 11, no. 11 (2021), p. 5844-5856
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- Description: Dead animal biomass (carrion) is present in all terrestrial ecosystems, and its consumption, decomposition, and dispersal can have measurable effects on vertebrates, invertebrates, microbes, parasites, plants, and soil. But despite the number of studies examining the influence of carrion on food webs, there has been no attempt to identify how general ecological processes around carrion might be used as an ecosystem indicator. We suggest that knowledge of scavenging and decomposition rates, scavenger diversity, abundance, and behavior around carrion, along with assessments of vegetation, soil, microbe, and parasite presence, can be used individually or in combination to understand food web dynamics. Monitoring carrion could also assist comparisons of ecosystem processes among terrestrial landscapes and biomes. Although there is outstanding research needed to fully integrate carrion ecology and monitoring into ecosystem management, we see great potential in using carrion as an ecosystem indicator of an intact and functional food web. © 2021 The Authors. Ecology and Evolution published by John Wiley & Sons 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**
Soil chemical markers distinguishing human and pig decomposition islands : a preliminary study
- 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.
Convergence of social strategies in carrion breeding insects
- Authors: Charabidze, Damien , Trumbo, Stephen , Grzywacz, Andrze , Costa, James , Barton, Philip
- Date: 2021
- Type: Text , Journal article , Review
- Relation: BioScience Vol. 71, no. 10 (2021), p. 1028-1037
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- Description: Carrion is a highly ephemeral and nutrient rich resource, characterized by extreme biotic and abiotic stressors. We hypothesized that specific constraints of the carrion ecosystem, and especially its nutrient richness, ephemerality, and competition with microbes, have promoted the evolution of social behaviors in necrophagous insects. We show that group living is prevalent among early succession carrion breeding insects, suggesting that this trait has emerged as an adaptation to facilitate survival in the highly competitive environment of fresh carrion. We then highlight how developmental niche construction allows larvae to compete with microbes, efficiently feed on fresh cadavers, and rapidly reach maturity. We observed that larval societies and parental care are two different strategies responding to similar competitive and environmental constraints. We conclude that intra and interspecific competition on carrion are mitigated by social behavior. © 2021 The Author(s) 2021. Published by Oxford University Press on behalf of the American Institute of Biological Sciences. **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**
Outfoxing the fox : effect of prey odor on fox behavior in a pastoral landscape
- 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
Effects of digging by a native and introduced ecosystem engineer on soil physical and chemical properties in temperate grassy woodland
- Authors: Ross, Catherine , Munro, Nicola , Barton, Philip , Evans, Maldwyn , Gillen, John
- Date: 2019
- Type: Text , Journal article
- Relation: PeerJ Vol. 2019, no. 8 (2019), p.
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- Description: Temperate grasslands and woodlands are the focus of extensive restoration efforts worldwide. Reintroduction of locally extinct soil-foraging and burrowing animals has been suggested as a means to restore soil function in these ecosystems. Yet little is known about the physical and chemical effects of digging on soil over time and how these effects differ between species of digging animal, vegetation types or ecosystems. We compared foraging pits of a native reintroduced marsupial, the eastern bettong (Bettongia gaimardi) and that of the exotic European rabbit (Oryctolagus cuniculus). We simulated pits of these animals and measured pit dimensions and soil chemical properties over a period of 2 years. We showed that bettong and rabbit pits differed in their morphology and longevity, and that pits had a strong moderating effect on soil surface temperatures. Over 75% of the simulated pits were still visible after 2 years, and bettong pits infilled faster than rabbit pits. Bettong pits reduced diurnal temperature range by up to 25 ° C compared to the soil surface. We did not find any effects of digging on soil chemistry that were consistent across vegetation types, between bettong and rabbit pits, and with time since digging, which is contrary to studies conducted in arid biomes. Our findings show that animal foraging pits in temperate ecosystems cause physical alteration of the soil surface and microclimatic conditions rather than nutrient changes often observed in arid areas. © 2019 Ross et al. **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**
The use and utility of surrogates in biodiversity monitoring programmes
- Authors: Sato, Chloe , Westgate, Martin , Barton, Philip , Foster, Claire , O'Loughlin, Luke
- Date: 2019
- Type: Text , Journal article
- Relation: Journal of Applied Ecology Vol. 56, no. 6 (2019), p. 1304-1310
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- Description: **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**
Avian functional responses to landscape recovery
- 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).
How practitioners integrate decision triggers with existing metrics in conservation monitoring
- 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
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- 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**
Contrasting effects of mosaic structure on alpha and beta diversity of bird assemblages in a human-modified landscape
- 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
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- 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
Cross-taxonomic surrogates for biodiversity conservation in human-modified landscapes – A multi-taxa approach
- Authors: Yong, Ding , Barton, Philip , Ikin, Karen , Evans, Maldwyn , Crane, Mason
- Date: 2018
- Type: Text , Journal article
- Relation: Biological Conservation Vol. 224, no. (2018), p. 336-346
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- Description: Cross-taxonomic surrogates are often used in conservation planning because inventorying large suites of taxa is either not feasible or too costly. However, cross-taxonomic surrogates are seldom tested rigorously using both correlational and representation-based approaches at the spatial scales at which conservation management occurs. Here, we evaluated the effectiveness of five ecologically contrasting taxa (birds, herpetofauna, wild bees, beetles, trees) as cross-taxonomic surrogates in native woodland patches within a heavily modified, farming and plantation-dominated landscape. We first compared species richness and compositional heterogeneity across taxa before testing for cross-taxonomic congruence using a correlative approach. We then quantified how well each taxon incidentally represented other taxa in their best patch sets, and the costs of doing so using a complementarity-based approach. We found significant pairwise associations between some taxa (birds, bees), but no single taxon was strongly correlated with all other taxa. Woodland patch sets prioritised for beetles represented other taxa best, followed by birds, but were the costliest and required the largest amount of woodland. This contrasted with patch sets prioritised for wild bees or herpetofauna, which achieved higher representation of other taxa at lower costs. Our study highlighted the influence of taxon-specific patterns of diversity and heterogeneity on how remnant vegetation patches should be prioritised for conservation, a consideration not immediately obvious in correlative analyses of surrogacy. Second, taxa that are not the most speciose (e.g. wild bees) can be efficient surrogates, achieving higher incidental representation for other taxa at lower costs. Thus, while species-rich taxa are ideal as surrogates for prioritising conservation, conservation planners should not overlook the potential of less speciose taxa such as bees, while considering the cost-effectiveness of surveying multiple different taxa. © 2018. **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**
Beetle’s responses to edges in fragmented landscapes are driven by adjacent farmland use, season and cross-habitat movement
- 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
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- 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.
Effects of fire regime on plant species richness and composition differ among forest, woodland and heath vegetation
- 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
Tests of predictions associated with temporal changes in Australian bird populations
- Authors: Lindenmayer, David , Lane, Peter , Westgate, Martin , Scheele, Ben , Barton, Philip
- Date: 2018
- Type: Text , Journal article
- Relation: Biological Conservation Vol. 222, no. (2018), p. 212-221
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- Description: Global biodiversity loss is the cumulative result of local species declines. To combat biodiversity loss, detailed information on the temporal trends of at-risk species at local scales is needed. Here we report the results of a 13-year study of temporal change in bird occupancy in one of the most heavily modified biomes worldwide; the temperate woodlands of south-eastern Australia. We sought to determine if temporal changes in bird species were different between three broad native vegetation types (old-growth woodland, regrowth woodland and restoration plantings) and between species traits (body size, migratory status, rarity, woodland dependency, or diet). We found evidence of decline for over a quarter of all bird species for which we had sufficient data for detailed analysis (30 out of 108 species). In contrast, only 14 species increased significantly. Temporal change of birds was linked to life-history attributes, with patterns often being habitat-dependent. Nectarivores and large-bodied birds declined across all vegetation types, whereas small-bodied species increased, particularly in restoration plantings. Contrasting with patterns documented elsewhere, resident but not migratory species declined, with this trend strongest in restoration plantings. Finally, our analyses showed that, as a group, common birds tended to decline whereas rare birds tended to increase, with effects for both most pronounced in restoration plantings. Our results highlight the benefit of targeted restoration planting for some species, but also demonstrate that many common species that have long-persisted in human-dominated landscapes are experiencing severe declines. © 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**
A long-term habitat fragmentation experiment leads to morphological change in a species of carabid beetle
- 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
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- 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
Conservation conundrums and the challenges of managing unexplained declines of multiple species
- 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**
Species co-occurrence networks show reptile community reorganization under agricultural transformation
- Authors: Kay, Geoffrey , Tulloch, Ayesha , Barton, Philip , Cunningham, Saul , Driscoll, Don , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Ecography Vol. 41, no. 1 (2018), p. 113-125
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- Description: Agricultural transformation represents one of the greatest threats to biodiversity, causing degradation and loss of habitat, leading to changes in the richness and composition of communities. These changes in richness and composition may, in turn, lead to altered species co-occurrence, but our knowledge of this remains limited. We used a novel co-occurrence network approach to examine the impact of agricultural transformation on reptile community structure within two large (> 172 000 km2; 224 sites) agricultural regions in southeastern Australia. We contrasted assemblages from sites surrounded by intact and modified landscapes and tested four key hypotheses that agricultural transformation leads to (H1) declines in species richness, (H2) altered assemblages, (H3) declines in overall co-occurrence, and (H4) complex restructuring of pairwise associations. We found that modified landscapes differed in composition but not richness compared with intact sites. Modified landscapes were also characterized by differences in co-occurrence network structure; with species sharing fewer sites with each other (reduced co-occurrence connectance), fewer highly-connected species (truncation of the frequency distribution of co-occurrence degree) and increased modularity of co-occurrence networks. Critically, overall loss of co-occurrence was underpinned by complex changes to the number and distribution of pair-wise co-occurrence links, with 41–44% of species also gaining associations with other species. Change in co-occurrence was not correlated with changes in occupancy, nor by functional trait membership, allowing a novel classification of species susceptibility to agricultural transformation. Our study reveals the value of using co-occurrence analysis to uncover impacts of agricultural transformation that may be masked in conventional studies of species richness and community composition. © 2017 The Authors
Seal carrion is a predictable resource for coastal ecosystems
- Authors: Quaggiotto, Maria-Martina , Barton, Philip , Morris, Christopher , Moss, Simon , Pomeroy, Patrick
- Date: 2018
- Type: Text , Journal article
- Relation: Acta Oecologica Vol. 88, no. (2018), p. 41-51
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- Description: The timing, magnitude, and spatial distribution of resource inputs can have large effects on dependent organisms. Few studies have examined the predictability of such resources and no standard ecological measure of predictability exists. We examined the potential predictability of carrion resources provided by one of the UK's largest grey seal (Halichoerus grypus) colonies, on the Isle of May, Scotland. We used aerial (11 years) and ground surveys (3 years) to quantify the variability in time, space, quantity (kg), and quality (MJ) of seal carrion during the seal pupping season. We then compared the potential predictability of seal carrion to other periodic changes in food availability in nature. An average of 6893 kg of carrion ∙yr−1 corresponding to 110.5 × 103 MJ yr−1 was released for potential scavengers as placentae and dead animals. A fifth of the total biomass from dead seals was consumed by the end of the pupping season, mostly by avian scavengers. The spatial distribution of carcasses was similar across years, and 28% of the area containing >10 carcasses ha−1 was shared among all years. Relative standard errors (RSE) in space, time, quantity, and quality of carrion were all below 34%. This is similar to other allochthonous-dependent ecosystems, such as those affected by migratory salmon, and indicates high predictability of seal carrion as a resource. Our study illustrates how to quantify predictability in carrion, which is of general relevance to ecosystems that are dependent on this resource. We also highlight the importance of carrion to marine coastal ecosystems, where it sustains avian scavengers thus affecting ecosystem structure and function. © 2018 Elsevier Masson SAS. **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**
Disentangling the effects of farmland use, habitat edges, and vegetation structure on ground beetle morphological traits
- 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**