Dissertations / Theses: 'Australia's biodiversity'

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Rhodes, Monika, and n/a. "The Ecology and Conservation of the White-Striped Freetail Bat (Tadarida australis) in Urban Environments." Griffith University. Australian School of Environmental Studies, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070314.114451.

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Of all anthropogenic pressures, urbanisation is one of the most damaging, and is expanding in its influence throughout the world. In Australia, 90% of the human population live in urban centres along the eastern seaboard. Before European settlement in the early 1800s, much of the Australia's East coast was dominated by forests. Many of the forest dependent fauna have had to adapt to forest fragmentation and habitat loss resulting from clearing for urbanisation. However, relatively few studies have investigated the impact of urbanisation on biodiversity. This is especially true for the remaining fauna in large metropolitan areas, such as Melbourne, Sydney and Brisbane. The physical and conceptual context of this thesis is the increasing impact of urbanisation and the potentially threatening factors to forest dependent fauna. Bats were selected because they comprise a third of Australia's mammal species, and therefore form a major component of Australia's biodiversity. Very little is known about the ecology and conservation biology of hollow-dependent bats in general, but particularly in urban environments. The study was conducted in Brisbane, south-east Queensland, one of Australia's most biodiverse regions. More than a third of Australia's bat species occur in this region. A large insectivorous bat, the white-striped freetail bat (Tadarida australis), was selected to study two key resources in this urban area - hollow availability and foraging habitat. This thesis also examined if artificial roost habitat could provide temporary roosts for white-striped freetail bats and other insectivorous bats and assessed whether these bat boxes can be used as a conservation tool in urban environments where natural hollow-availability is limited. The white-striped freetail bat is an obligate hollow-dweller and roosted largely in hollows of old or dead eucalypts throughout Brisbane's urban matrix. These roost trees harboured significantly more additional hollow-dependent species compared to control trees of similar age, height, and tree diameter. Roost cavities inside trees often exceeded 30 cm in diameter. Furthermore, maternity colonies used cavities of hollow trunks, which often extended into major branches, to roost in big numbers. Therefore artificial alternatives, such as small bat boxes, may provide temporary shelter for small roosting groups, but are unlikely to be suitable substitutes for habitat loss. Although five bat species used bat boxes during this study, the white-striped freetail bat was not attracted into bat boxes. Roost-switching behaviour was then used to quantify associations between individual white-striped freetail bats of a roosting group. Despite differences in gender and reproductive seasons, the bats exhibited the same behaviour throughout three radio-telemetry periods and over 500 bat-days of radio-tracking: each roosted in separate roosts, switched roosts very infrequently, and associated with other tagged bats only at a communal roost. Furthermore, the communal roost exhibited a hub of socialising between members of the roosting group especially at night, with vocalisation and swarming behaviour not found at any of the other roosts. Despite being spread over a large geographic area (up to 200 km2), each roost was connected to others by less than three links. One roost (the communal roost) defined the architecture of the network because it had the most links. That the network showed scale-free properties has profound implications for the management of the habitat trees of this roosting group. Scale-free networks provide high tolerance against stochastic events such as random roost removals, but are susceptible to the selective removal of hub nodes, such as the communal roost. The white-striped freetail bat flew at high speed and covered large distances in search for food. It foraged over all land-cover types found in Brisbane. However, its observed foraging behaviour was non-random with respect to both spatial location and the nature of the ground-level habitat. The main feeding areas were within three kilometers of the communal roost, predominantly over the Brisbane River flood plains. As the only mammal capable of flight, bats can forage above fragmented habitats. However, as this study showed, hollow-dependent insectivorous bats, including free-tailed bats, are specialised in their roosting requirements. The ongoing protection of hollow-bearing trees, and the ongoing recruitment of future hollow-bearing trees, is essential for the long-term conservation of these animals in highly fragmented landscapes. Furthermore, loss of foraging habitat is still poorly understood, and should be considered in the ongoing conservation of bats in urban environments.

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2

Rhodes, Monika. "The Ecology and Conservation of the White-Striped Freetail Bat (Tadarida australis) in Urban Environments." Thesis, Griffith University, 2006. http://hdl.handle.net/10072/367292.

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Abstract:

Of all anthropogenic pressures, urbanisation is one of the most damaging, and is expanding in its influence throughout the world. In Australia, 90% of the human population live in urban centres along the eastern seaboard. Before European settlement in the early 1800s, much of the Australia's East coast was dominated by forests. Many of the forest dependent fauna have had to adapt to forest fragmentation and habitat loss resulting from clearing for urbanisation. However, relatively few studies have investigated the impact of urbanisation on biodiversity. This is especially true for the remaining fauna in large metropolitan areas, such as Melbourne, Sydney and Brisbane. The physical and conceptual context of this thesis is the increasing impact of urbanisation and the potentially threatening factors to forest dependent fauna. Bats were selected because they comprise a third of Australia's mammal species, and therefore form a major component of Australia's biodiversity. Very little is known about the ecology and conservation biology of hollow-dependent bats in general, but particularly in urban environments. The study was conducted in Brisbane, south-east Queensland, one of Australia's most biodiverse regions. More than a third of Australia's bat species occur in this region. A large insectivorous bat, the white-striped freetail bat (Tadarida australis), was selected to study two key resources in this urban area - hollow availability and foraging habitat. This thesis also examined if artificial roost habitat could provide temporary roosts for white-striped freetail bats and other insectivorous bats and assessed whether these bat boxes can be used as a conservation tool in urban environments where natural hollow-availability is limited. The white-striped freetail bat is an obligate hollow-dweller and roosted largely in hollows of old or dead eucalypts throughout Brisbane's urban matrix. These roost trees harboured significantly more additional hollow-dependent species compared to control trees of similar age, height, and tree diameter. Roost cavities inside trees often exceeded 30 cm in diameter. Furthermore, maternity colonies used cavities of hollow trunks, which often extended into major branches, to roost in big numbers. Therefore artificial alternatives, such as small bat boxes, may provide temporary shelter for small roosting groups, but are unlikely to be suitable substitutes for habitat loss. Although five bat species used bat boxes during this study, the white-striped freetail bat was not attracted into bat boxes. Roost-switching behaviour was then used to quantify associations between individual white-striped freetail bats of a roosting group. Despite differences in gender and reproductive seasons, the bats exhibited the same behaviour throughout three radio-telemetry periods and over 500 bat-days of radio-tracking: each roosted in separate roosts, switched roosts very infrequently, and associated with other tagged bats only at a communal roost. Furthermore, the communal roost exhibited a hub of socialising between members of the roosting group especially at night, with vocalisation and swarming behaviour not found at any of the other roosts. Despite being spread over a large geographic area (up to 200 km2), each roost was connected to others by less than three links. One roost (the communal roost) defined the architecture of the network because it had the most links. That the network showed scale-free properties has profound implications for the management of the habitat trees of this roosting group. Scale-free networks provide high tolerance against stochastic events such as random roost removals, but are susceptible to the selective removal of hub nodes, such as the communal roost. The white-striped freetail bat flew at high speed and covered large distances in search for food. It foraged over all land-cover types found in Brisbane. However, its observed foraging behaviour was non-random with respect to both spatial location and the nature of the ground-level habitat. The main feeding areas were within three kilometers of the communal roost, predominantly over the Brisbane River flood plains. As the only mammal capable of flight, bats can forage above fragmented habitats. However, as this study showed, hollow-dependent insectivorous bats, including free-tailed bats, are specialised in their roosting requirements. The ongoing protection of hollow-bearing trees, and the ongoing recruitment of future hollow-bearing trees, is essential for the long-term conservation of these animals in highly fragmented landscapes. Furthermore, loss of foraging habitat is still poorly understood, and should be considered in the ongoing conservation of bats in urban environments.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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3

Presti, Maia M. "Designing For The Continued Survival Of Wildlife: A Case Study On Wildlife Habitat Design In Australia's Alice Springs Desert Park." Scholarship @ Claremont, 2018. http://scholarship.claremont.edu/scripps_theses/1136.

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This thesis explores the nexus between landscape design processes and the conservation of wildlife diversity. Extinction of earth’s unique and diverse animal species is progressing at unprecedented rates, due to humanity’s profound alteration of the natural landscape. Scientific literature increasingly points towards opportunities in the urban and landscape design fields to this issue. Unfortunately, the science and needs of wildlife are rarely integrated in rigorous ways in the planning and design of human landscapes. This gap in professional practice protocols and regulatory frameworks in much of the western world is explored and raises questions about how design can successfully protect, restore, and even re-create viable habitat and linkages for wildlife that is integrated with human landscape. Australia has modeled new integrated wildlife-centric design approaches and projects there demonstrate accumulated expertise in the specific area of wildlife habitat design. Through a case study of Australia’s Alice Springs Desert Park, I argue that balancing human and wildlife needs at every step of the design and building process is necessary for successful wildlife habitat design. This integrated approach does not view wildlife and humans as independent, but rather as two interdependent habitat participants that must coexist to ensure the future of both.

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4

Kloser, Rudolf J. "Seabed biotope characterisation based on acoustic sensing." Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/524.

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The background to this thesis is Australia’s Oceans Policy, which aims to develop an integrated and ecosystem-based approach to planning and management. An important part of this approach is the identification of natural regions in regional marine planning, for example by establishing marine protected areas for biodiversity conservation. These natural regions will need to be identified on a range of scales for different planning and management actions. The scale of the investigation reported in this thesis is applicable to spatial management at 1 km to 10 km scale and monitoring impacts at the 10s of m to 1 km biotope scale. Seabed biotopes represent a combination of seabed physical attributes and related organisms. To map seabed biotopes in deep water, remote sensing using a combination of acoustic, optical and physical sensors is investigated. The hypothesis tested in this thesis is that acoustic bathymetry and backscatter data from a Simrad EM1002 multi-beam sonar (MBS) can be used to infer (act as a surrogate of) seabed biotopes. To establish a link between the acoustic data and seabed biotopes the acoustic metrics are compared to the physical attributes of the seabed in terms of its substrate and geomorphology at the 10s m to 1 km scale using optical and physical sensors. At this scale the relationship between the dominant faunal functional groups and both the physical attributes of the seabed and the acoustic data is also tested. These tests use data collected from 14 regions and 2 biomes to the south of Australia during a voyage in 2000. Based on 62 reference sites of acoustic, video and physical samples, a significant relationship between ecological seabed terrain types and acoustic backscatter and bathymetry was observed.These ecological terrain types of soft-smooth, soft-rough, hard-smooth and hard-rough were chosen as they were the most relevant to the biota in their ability to attach on or burrow into the seabed. A seabed scattering model supported this empirical relationship and the overall shape of backscatter to incidence angle relationship for soft and hard seabed types. The correlation between acoustic data (backscatter mean and standard deviation) and the visual and physical samples was most consistent between soft-smooth and hard-rough terrain types for a large range of incidence angles (16o to 70o). Using phenomenological backscatter features segmented into 10 common incidence angle bins from -70o to 70o the length resolution of the data decreased to 0.55 times depth. The decreased resolution was offset by improved near normal incidence (0o to 30o) seabed type discrimination with cross validation error reducing from 32% to 4%. A significant relationship was also established between the acoustic data and the dominant functional groups of fauna. Faunal functional groups were based on the ecological function, feeding mode and substrate preference, with 8 out of the 10 groups predicted with 70% correctness by the four acoustically derived ecological terrain types. Restricting the terrain classification to simple soft and hard using the acoustic backscatter data improved the prediction of three faunal functional groups to greater than 80%. Combining the acoustic bathymetry and backscatter data an example region, Everard Canyon, was interpreted at a range of spatial scales and the ability to predict the preferred habitat of a stalked crinoid demonstrated.Seabed terrain of soft and hard was predicted from the acoustic backscatter data referenced to a common seabed incidence angle of 40o. This method of analysis was selected due to its combined properties of high spatial resolution, consistent between terrain discrimination at the widest range of incidence angles and consistent data quality checking at varying ranges. Based in part on the research reported in this thesis a mid-depth Simrad EM300 multibeam sonar was purchased for use in Australian waters. A sampling strategy is outlined to map all offshore waters with priority within the 100 m to 1500 m depths.

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5

Kloser, Rudolf J. "Seabed biotope characterisation based on acoustic sensing." Curtin University of Technology, Faculty of Science and Engineering, Department of Imaging and Applied Physics, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=18566.

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Abstract:

The background to this thesis is Australia’s Oceans Policy, which aims to develop an integrated and ecosystem-based approach to planning and management. An important part of this approach is the identification of natural regions in regional marine planning, for example by establishing marine protected areas for biodiversity conservation. These natural regions will need to be identified on a range of scales for different planning and management actions. The scale of the investigation reported in this thesis is applicable to spatial management at 1 km to 10 km scale and monitoring impacts at the 10s of m to 1 km biotope scale. Seabed biotopes represent a combination of seabed physical attributes and related organisms. To map seabed biotopes in deep water, remote sensing using a combination of acoustic, optical and physical sensors is investigated. The hypothesis tested in this thesis is that acoustic bathymetry and backscatter data from a Simrad EM1002 multi-beam sonar (MBS) can be used to infer (act as a surrogate of) seabed biotopes. To establish a link between the acoustic data and seabed biotopes the acoustic metrics are compared to the physical attributes of the seabed in terms of its substrate and geomorphology at the 10s m to 1 km scale using optical and physical sensors. At this scale the relationship between the dominant faunal functional groups and both the physical attributes of the seabed and the acoustic data is also tested. These tests use data collected from 14 regions and 2 biomes to the south of Australia during a voyage in 2000. Based on 62 reference sites of acoustic, video and physical samples, a significant relationship between ecological seabed terrain types and acoustic backscatter and bathymetry was observed.
These ecological terrain types of soft-smooth, soft-rough, hard-smooth and hard-rough were chosen as they were the most relevant to the biota in their ability to attach on or burrow into the seabed. A seabed scattering model supported this empirical relationship and the overall shape of backscatter to incidence angle relationship for soft and hard seabed types. The correlation between acoustic data (backscatter mean and standard deviation) and the visual and physical samples was most consistent between soft-smooth and hard-rough terrain types for a large range of incidence angles (16o to 70o). Using phenomenological backscatter features segmented into 10 common incidence angle bins from -70o to 70o the length resolution of the data decreased to 0.55 times depth. The decreased resolution was offset by improved near normal incidence (0o to 30o) seabed type discrimination with cross validation error reducing from 32% to 4%. A significant relationship was also established between the acoustic data and the dominant functional groups of fauna. Faunal functional groups were based on the ecological function, feeding mode and substrate preference, with 8 out of the 10 groups predicted with 70% correctness by the four acoustically derived ecological terrain types. Restricting the terrain classification to simple soft and hard using the acoustic backscatter data improved the prediction of three faunal functional groups to greater than 80%. Combining the acoustic bathymetry and backscatter data an example region, Everard Canyon, was interpreted at a range of spatial scales and the ability to predict the preferred habitat of a stalked crinoid demonstrated.
Seabed terrain of soft and hard was predicted from the acoustic backscatter data referenced to a common seabed incidence angle of 40o. This method of analysis was selected due to its combined properties of high spatial resolution, consistent between terrain discrimination at the widest range of incidence angles and consistent data quality checking at varying ranges. Based in part on the research reported in this thesis a mid-depth Simrad EM300 multibeam sonar was purchased for use in Australian waters. A sampling strategy is outlined to map all offshore waters with priority within the 100 m to 1500 m depths.

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6

Dhanasekaran, Vijaykrishna. "Freshwater fungi biodiversity, origins and molecular taxonomy /." Thesis, Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B32017583.

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7

Azarbayjani, Fathollah Fathi, of Western Sydney Hawkesbury University, Faculty of Science and Technology, and School of Science. "Assessment of estimators and factors affecting arboreal arthropod biodiversity on Melaleuca Linariifolia." THESIS_FST_SS_Azarbayjani_F.xml, 1997. http://handle.uws.edu.au:8081/1959.7/246.

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This study was carried out in a woodland on the campus of University of Western Sydney at Richmond, Australia to investigate seasonal effects and recovery speed of arboreal arthropods after disturbance. Twenty one pairs of Melaleuca linariifolia Sm. trees were sampled using insecticide spraying in a log2 nine period sequence (1-32) of weeks supplemented by additional samples to incorporate seasonal (weeks 24 and 48) and annual (week 52) samples. Using species accumulation curves, it was found that four collectors provided a reasonable representation of a tree's fauna and that a single tree does not provide a representative sample of the arthropod fauna found on trees of this species in the study area. The application of richness and evenness indices in different seasons showed significant changes in diversity. It was clear from the findings of the study that careful attention needs to be paid to experimental design. Under replication is the normal situation in previous studies and the effects of location, season and disturbance are all critical factors affecting the estimation of diversity.
Doctor of Philosophy (PhD)

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Smith, Graeme. "The contribution of silverfish (insecta: zygentoma) to Australian invertebrate biodiversity and endemism." Thesis, Federation University Australia, 2018. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/164489.

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Silverfish (Order Zygentoma) are quite abundant in Australia but have been largely overlooked. This thesis examines the biodiversity of the Australian fauna at the level of genus, describing at least one representative species from each named genus and some new genera. The endemism of the fauna is evaluated and likely zoogeographic origins proposed. Over 4000 specimens were examined, either collected by the author, borrowed from or examined within museum collections or supplied by organisations and individuals conducting fauna surveys. Twenty- seven new native species are described and two redescribed, bringing the number of named species recorded in Australia to 74. Five new genera are described and four additional genera recorded in Australia for the first time including autochthonous representatives of three subfamilies previously unrecognised as native to Australia (Acrotelsatinae, Lepismatinae and Coletiniinae). No representatives of the families Maindroniidae, Tricholepidiidae and Protrinemuridae were found. The subfamily Acrotelsatinae was redefined following a revision of the enigmatic genus Anisolepisma Paclt, 1967 with the unique structure of the thoracic sterna identified as diagnostic for the subfamily. Contrary to existing opinion, it is suggested that this is a fundamentally different and plesiomorphic character, rather than an apomorphic reduction of the free thoracic sterna. A monograph of the Australian Zygentoma is presented, including a summary of the biology of the order, a key to and diagnoses of the genera, as well as information on the known habitat and distribution of each genus and a discussion of their zoogeography. At the suprageneric level the fauna is less diverse than seen in other zoogeographic regions but appears to be rich in the number of species. The fauna displays a high degree of endemism with 91% of described species and 52% of the genera known only from Australia. Some genera appear to be ancient and probably represent a Pangean element in the Australian fauna. Others appear to have emerged in the late Jurassic when Africa was still joined to Gondwana, while some may have appeared in the Cretaceous or Palaeocene when Australia and South America were connected to Gondwana. More recent links with the Asian fauna are limited and there appears to be no widespread highly mobile global species other than the six introduced anthropophilic species. Maps of the worldwide distribution records extracted from the taxonomic literature are used to discuss the zoogeography of the subfamilies and tribes present in Australia. Molecular data using two mitochondrial genes (16S and COI) as well as a nuclear gene (28S) were compared with detailed morphological and morphometric analysis to examine populations initially determined as Heterolepisma sclerophylla or close to it. Distances of 0.9– 1.8% or greater in 28S, and 7.2–14% in COI were associated with morphologically distinct species. A southern Queensland population was found to be genetically, morphometrically and morphologically very distinct from those collected in NSW and was described as new (Heterolepisma sp. B). Six well-defined barcode clusters (“lineages”) were identified within the NSW populations, each with >4% divergence in COI sequences and each geographically restricted. Intracluster divergences are also large, and despite the well-supported phylogeny no clear “barcode gap” (distinction between intracluster and intercluster distances) was found for three of the six NSW populations. The 28S data distinguished only four of the six COI clusters from NSW with essentially no variation within each cluster. The 28S data generally aligned well with morphological evidence, clearly identifying Heterolepisma sp. B as a distinct species, and supporting also the description of Heterolepisma sp. A even though it only appears to differ from H. sclerophylla in the number of styli. Similar genetic distances are observed in 28S data for H. sclerophylla populations from North Nowra, Glenbrook/Burralow/Nattai and Megalong, however the Broulee and Wellington populations have identical 28S sequences. The low levels of variation in 28S sequences between NSW populations accord with the lack of unambiguous morphological differences.
Doctor of Philosophy

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Noonan, David J. "Toward a bioregional policy and practice for the conservation of threatened biodiversity /." Title page, contents and abstract only, 1994. http://web4.library.adelaide.edu.au/theses/09ENV/09envn817.pdf.

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10

Haouchar, Dalal. "Using ancient DNA to investigate extinction, extirpation and past biodiversity of Australian macropods." Thesis, Haouchar, Dalal (2016) Using ancient DNA to investigate extinction, extirpation and past biodiversity of Australian macropods. PhD thesis, Murdoch University, 2016. https://researchrepository.murdoch.edu.au/id/eprint/32550/.

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The field of ancient DNA (aDNA) involves the isolation and retrieval of trace amounts of degraded DNA from a variety of substrates including fossils, sediments and historical material. The fragmentary nature of aDNA necessitates the use of methods with the ability to capture and amplify short segments of DNA. Collectively aDNA studies have made significant and unique contributions to a wide field of research including conservation, population genetics, taxonomy and phylogeny. The primary aim of this thesis research is to explore the utility of aDNA techniques to study extirpation, extinction and past biodiversity of Australian macropods. Using a combination of historical, Holocene and Pleistocene aged fossils, this research will attempt to investigate what ancient mitochondrial DNA (mtDNA) can add to our knowledge of Australia’s macropods. Traditional aDNA techniques have largely been used to isolate mtDNA from single fossil samples - an example of this approach is shown in Chapter Two where a wellpreserved wallaby fossil bone from Depuch Island (Western Australia) was studied. The ancient mtDNA (cytochrome b and control region) data produced strong phylogenetic signal and shows that the Depuch Island rock-wallaby specimen is most similar to the mainland Petrogale lateralis lateralis. This finding has conservation implications for ongoing rehabilitation and translocation efforts in the Pilbara region. Chapter Three of this thesis also uses mitochondrial aDNA techniques, to explore questions regarding interrelationships and former distribution of a macropod species complex; Bettongia spp. Cytochrome b and control region data retrieved from 88 historical samples, along with ~214 already sequenced samples, place the most recent common ancestor of the brush-tailed bettongs at c. 2.5 Myr. Ancient mtDNA is suggestive of connectivity between what are now highly fragmented populations, a result that has implications for how critically endangered brush-tailed bettongs should be managed. Ancient DNA analyses and DNA sequencing technology have evolved over recent years and during the course of this study. Therefore in keeping up with the latest high-throughput sequencing (HTS) technology, aDNA analyses in ~70 bones and 20 sediment samples excavated from a Late Pleistocene–Holocene cave deposit on Kangaroo Island, South Australia was undertaken. Samples were selected from 15 stratigraphic layers, ranging in age from >20 ka to ~6.8 ka. The successful retrieval of bona fide aDNA sequences, back to at least 20 ka, demonstrates excellent longterm DNA preservation at the site. All unidentified bones that were screened revealed a number of taxa from the assemblage including, Macropus, Onychogalea, Potorous, Bettongia, Dasyurus, Rattus and Notechis. The results from this study add significant value to the late Pleistocene-mid-Holocene paleontological record, detailing the past diversity of flora and fauna on Kangaroo Island. Lastly, Chapter 5 introduces the latest molecular techniques in capturing and enriching highly fragmented aDNA bone from four sites across Australia. Ancient DNA extractions techniques, targeting ultra-short DNA fragments, were employed in an attempt to obtain Pleistocene-aged material. The warm conditions, a factor common in Australian caves, are not conductive to long-term DNA preservation at many sites. Shotgun sequencing was only successful on six bone samples (including one incisor) from a total of 25 samples that were screened. Three samples were successfully captured and enriched for endogenous DNA; one bettong sample generated 89.6% of a mtDNA genome with 5.4X coverage. Overall, the decay rate of DNA and preservation across all four sites was high, and extremely degraded, with an average fragment length between 47 bp and 57 bp. These data demonstrate that recovery of Pleistocene-aged aDNA from warm climate sites across Australia will remain a challenge and that better ways to screen and predict DNA survival are needed. This thesis presents a combination of work from multiple sites across Australia using a range of aDNA techniques and sequencing technologies that have evolved over the tenure of this thesis. Collectively, this body of work has demonstrated the value of integrating aDNA data into modern-day conservation decision-making and has contributed to a wider understanding of Australian macropods both past and present.

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Zuiddam, Sharon Angela. "A revision of the Western Australian species of the Australian harvestman genus Nunciella (Opiliones: Triaenonychidae)." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2015. https://ro.ecu.edu.au/theses/1636.

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Many regions around the world are renowned as biodiversity hotspots. South Western Australia is one of these. A combination of the recognised high biodiversity and a seemingly unbalanced species distribution of the genus Nunciella across Australia initiated the investigation into the diversity of the south western species of Nunciella. Previous descriptions indicate two of the 11 Nunciella species are found in this region, one of these with a very large recorded distribution in contradiction to the short range distribution of all the other species. Through observations of museum specimens it is hypothesised that there is a much larger species diversity to be found in Western Australia. The aim of this project was to determine if there are more species present than currently described. This was done through sequencing the genes cytochrome c oxidase subunit I (COI) and histone H3 (H3) combined with morphological analysis. The molecular analysis revealed strong COI support for at least seven Nunciella species in the area. As an unexpected result COI also provides support for a new genus with a further six species. H3 results had low support for species level delimitation though strong support for the two genera. The resulting DNA species are further supported by morphological characters suitable for species delimitation, enabling the identification of a further three morphological species. The holotype of Nunciella aspera (Pocock, 1903) was obtained and redescribed including images. Specimens from the type locality of the second species, N. karriensis Kauri, 1954 have been included in this study as well as observations made on the syntype of a synonymised species N. frontalis Roewer, 1931.It is also revealed that Nunciella species may live sympatrically. A secondary aim was to clarify the misconceptions presented in previous descriptions of N. aspera. A number of authors redescribed N. aspera with varying characters from a number of Western Australian locations. This research has identified support for the authors possibly being correct in their examination, though incorrect in their species diagnosis. In summary, this research provides morphological descriptions for ten new Nunciella species, a redescription of the holotype of the type species of Nunciella, brief analysis of the syntype of the synonymised N. frontalis, cautionary predictions on the status of N. karriensis and molecular and morphological support for a new genus with six species.

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Fitzsimons, James Andrew, and mikewood@deakin edu au. "The contribution of Multi-tenure reserve networks to biodiversity conservation." Deakin University. School of Ecology and Environment, 2004. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050817.103606.

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A consistent and integrated approach to nature conservation across the landscape and regardless of tenure is widely recognised as essential in ensuring the effective conservation of biodiversity. 'Multi-tenure reserve networks', which incorporate public and private lands managed for conservation, are considered a means of achieving landscape scale conservation. Biosphere Reserves (BR) and Conservation Management Networks (CMN) are characteristic models in Australia. This thesis aims to evaluate the role of such networks in protecting biodiversity, specifically by: (1) analysing the spatial configuration (size, shape, connectivity) of networks and their individual components; (2) evaluating the contribution of networks (in real terms and in reporting procedures) to biodiversity conservation objectives; (3) analysing the influence of the attitudes and perceptions of land managers on the functionality of networks; and (4) evaluating the influence of coordinating bodies on network functionality. In order to account for deficiencies in existing classifications of conservation lands, a new classification system was developed for this thesis - the Conservation Lands Classification. This classification incorporates conservation mechanisms on public and private lands and forms the basis for comparing network components in three Australian case studies - the Bookmark BR located in the Murray Mallee of South Australia, the Gippsland Plains CMN on the eastern Gippsland Plains of Victoria and the Grassy Box Woodlands CMN across the inland slopes of New South Wales. The spatial configuration of individual components within networks was measured using spatial analysis techniques within a geographic information system (GIS). GIS was also used to measure the contribution that networks made to a comprehensive, adequate and representative reserve system through the ecosystems they protected. The attitudes and perceptions of landowners and managers within the networks were obtained using questionnaires. Questionnaires were also sent to network coordinators. Statistical and descriptive analysis was conducted on the results. The sizes of individual components varied markedly between the three networks, however within each network public reserves were on average larger than private conservation lands. Although levels of physical connectivity varied between networks, Bookmark BR and Gippsland Plains CMN showed greater similarity to each other than to the Grassy Box Woodlands CMN. The findings raise important questions about the real and perceived differences in the BR and CMN models. All networks, and particularly those components outside the public protected area estate, contributed to enhancing the protection of ecosystems unrepresented or under-represented in the reserve system, although the extent of this contribution varied between networks. Trade-offs between reserve design efficiency and a contribution to a comprehensive, adequate and representative reserve system were evident between networks. Bookmark BR was characterised by high connectivity, strong reserve design integrity but a lower contribution to protecting under-reserved ecosystems, whereas the opposite was evident in the Grassy Box Woodlands CMN. Over 88% of managers considered their involvement in multi-tenure reserve networks to be a positive or very positive experience. A lack of resources and time for management were considered major limitations of these networks. The majority (80%) of private land managers within networks were willing to be included in a national reserve system of conservation lands. This has important implications for the Australian National Reserve System, which currently incorporates mostly public land. The changing nature of the network coordination arrangements suggests an organic fluid evolution of network structures is likely, contrasting with the desire for legalistic and administrative rigidity promoted by government agencies. The thesis concludes that all the networks studied contribute in varying degrees to biodiversity conservation. The key factors influencing the current and potential contribution that such networks make are: (1) the aims, directions and restrictions set by or imposed upon the coordinating body; and (2) the biophysical nature of the surrounding bioregion and resultant historical land use and tenure pattern. Although the successful operation of such 'multi-tenure' networks ultimately relies on the willing participation of private landholders, ongoing institutional support is likely to be required for maintaining networks in the longer term. Considering networks are increasingly formed outside of the influence of government institutions, this presents a significant challenge for effective coordinated conservation.

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Radford, Benedict. "Cross-shelf coral reef biodiversity : does data and ecological theory fit with habitat-based species conservation models?" University of Western Australia. School of Earth and Geographical Sciences, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0212.

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[Truncated abstract] Selection of priority areas for Marine Park conservation is often compromised by the lack of comprehensive biodiversity data and the resources and expertise necessary to gain this information directly by sampling. One cost effective alternative is the use of species groups or indicator species as surrogates for total biodiversity. However use of these surrogates requires an ecological understanding of how they reflect biodiversity gradients. A framework for unravelling these relationships has been suggested that involves relating species biodiversity to different and competing ecological models using appropriate statistical analysis. I use this framework to explore coral species biodiversity over a range of environmental gradients encompassing the North West Shelf of Australia and the Great Barrier Reef in North East Australia. ... I assessed physiological responses of corals to physical factors to corroborate crossshelf patterns in species biodiversity. Finally, I investigated to what extent coral cooccurrence based species groups (or guilds) can be used as surrogates for total coral biodiversity. The major findings of this thesis were: i) coral biodiversity along cross-shelf environments was highly correlated to specific gradients of abiotic reef conditions; ii) larval modelling indicates the potential for significant connectivity across continentalshelf environments such that differences in species distribution are not simply as a result of self seeding. iii) similar correlative patterns were demonstrated for coral species that occur along comparable abiotic gradients in reef areas of both Eastern and Western Australia, suggesting a causal relationship between the physical environment and coral biodiversity; iv) coral physiological parameters measured using lipid fractions independently corroborated the hypothesis that there is a biological basis for observed coral distributions; v) reef coral communities are not highly structured across abiotic physical gradients and biodiversity across the shelf increases as conditions become suitable for a wider range of species; vi) total coral biodiversity can be estimated very accurately (within r2 values ranging from 0.75 to 0.90) using a small number (15-30) of optimally chosen indictor species using the randomForest statistical method. These results suggest coral biodiversity over cross-shelf environments conforms most closely to the

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Dorjgurhem, Batbold. "Regional biodiversity management strategy : case study on the Flinders Ranges." Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09AS/09asd699.pdf.

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Bibliography: leaves 107-117. This thesis examines the rationale for managing biological diversity on a regional basis and develops recommendations for the use of two computational methods in biodiversity management planning by conducting a case study in the Flinders Ranges, centred on the Yellow-footed Rock Wallaby (abstract)

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Just, Michael. "Understanding the seed ecology of southwest Australian Rutaceae to improve restoration in a biodiversity hotspot." Thesis, Curtin University, 2022. http://hdl.handle.net/20.500.11937/88660.

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In southwest Australia there is a significant need to restore vegetation communities impacted by anthropogenic activities. The series of experiments undertaken over the course of this thesis focus on a notoriously difficult-to-germinate plant family, the Rutaceae. Through the application of field- and lab-based experiments, avenues for seed-based propagation of southwest Australian Rutaceae have been developed, allowing for more effective restoration approaches based upon an improved understanding of seed ecology.

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Reeve, Martin. "Fragmented landscape and fragmented law : threatened species management in South Australia /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ENV/09envr331.pdf.

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Clemente, Pedro Miguel Rodrigues Jacinto. "Designing market-based instruments for biodiversity conservation: learning with the Australian experience and evaluating Portugal's potential." Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/2662.

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia do Ambiente, perfil Gestão de Sistemas Ambientais
Biodiversity has been increasingly recognized as one of the key elements in human development and well-being. The loss of biodiversity is considered alarming not only because of its ethical and esthetical value, but also, because it comprises a variety of services essential for the health, regulation and prosperity of the biosphere. Given their significance, one might expect that the ecosystem services would be prized by markets and explicitly protected by the law, however, neither has been the case. International experience has shown that market-based instruments (MBIs), which basically provide economic incentives to modify behaviour, may be a more effective way to achieve many environmental goals, often yielding better results by harnessing the powerful cost-benefit motivations of businesses and individuals. This study intends to demonstrate the potential of market-based instruments in biodiversity conservation, particularly in protected areas. However biodiversity is not restricted to the network of national parks and other protected areas on state-owned land, it also needs to be protected and managed on privately-owned land. The goal of this work is to design a MBI, to be implemented in Portugal, in order to incentive private landowners in protected areas to achieve economic and social development without depleting the natural capital available. The design of the instrument started with the assessment of MBIs already running, with a special focus in the Australian experience. A methodology is proposed for that assessment in order to standardize the approach and analysis of this type of instrument. To overcome uncertainties and to get more information on the likely costs and benefits it is considered preferable to use an already trialled mechanism as basic framework. The instrument is designed using the basics of the Liverpool Plains Scheme (Australia), but some changes are introduced to improve it and make it more suitable to Portuguese reality. A potential target area in Portugal is selected according to several criteria, as a case study to illustrate the instrument application. It is proposed an implementation program and schedule. MBIs offer an opportunity to integrate biodiversity conservation into the economic market, however without a strong economic foundation, designing market mechanisms can result in costly mistakes. The success of this instrument will mainly depend on the ability to motivate the landowners to participate, in order to create competition between them, which will result in better outcomes at a lower cost. On the other hand, the ability to involve companies in the scheme, basically increasing the demand, will be decisive to its economic sustainability and growth. These are the keys features that will decide the success or failure of its implementation.

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Bohigas, Ivar. "Indigenous peoples, protected areas and biodiversity conservation : a study of Australia´s obligations under international law." Thesis, Stockholms universitet, Juridiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-120750.

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Pert, Petina Lesley, and petina pert@bigpond com. "Biodiversity Conservation at the Bioregional Level: a case study from the Burt Plain Bioregion of Central Australia." RMIT University. Mathematical and Geospatial Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070209.120654.

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This thesis considers ways to improve biodiversity conservation at the bioregional level in Australia through the use of geospatial science technologies and biological modelling techniques. Following a review of approaches to biodiversity conservation at the bioregional level, including the roles and potential of geospatial science technologies in this regard, I consider biodiversity modelling using a case study of the Burt Plain bioregion in central Australia that focuses on selected taxa, ecosystems and landscapes. The Burt Plain bioregion was chosen since it is one of 19 bioregions nationally that has been given a 'very high' priority status for biological survey, assessment and potential reservation of land for conservation purposes. The specific research objectives for the Burt Plain bioregion study were to: · describe the species composition, distribution and nature of the dominant vegetation communities within the bioregion; · characterise environmental niche of communities with respect to selected environmental and management variables - latitude, longitude, climate, land systems and land units, geology, hydrography, topography, and tenure; · analyse how well or otherwise taxa have been sampled (during previous ground surveys) with respect to geographical and environmental variables; Biodiversity conservation at the bioregional level · develop and compare quantitative habitat models of the potential distribution of selected species based on presence-only distributional data; and · examine the significance of radiometric data as a potential correlate and predictor of the distribution of those selected species. National conservation initiatives such as the bioregional approach and international initiatives such as the biosphere reserves program to support the planning and management of biodiversity conservation are discussed in chapter two. The scientific and related processes underpinning the development of bioregions and strategies across the Australian states and territories are then considered. An important finding arising from this review is the need to improve biological information, especially through systematic surveys and on-going monitoring of ecosystems and populations of species, at the bioregional level to inform land use allocation and management. This finding is consistent with one of the general aims of the thesis to improve the spatial modelling techniques available for bioregional assessment and biodiversity conservation. In chapter three I review the role and limitations of geospatial technologies currently employed for biodiversity conservation management. Current developments and applications of GIS and remote sensing to wildlife research, conservation gap analysis and conservation reserve design are considered. Geographic information systems (GIS) are now routinely used by ecologists to Biodiversity conservation at the bioregional level analyse spatial data. Although various forms of GIS have been available for 15 to 25 years, the biological applications of GIS have figured most prominently in the ecological literature only in the past 15 years. The use of computer-generated models to simulate environmental events can provide a greater understanding of ecosystems, and offers improved predictive powers to conservation and land managers. The decision support offered by computer-based modelling techniques appears likely to underpin conservation and management decisions much more into the future providing that adequate biological and other datasets are available for this purpose. Dominant vegetation communities and various environmental gradients were analysed to characterise environmental niches at the bioregional scale for the Burt Plain bioregion (Chapter 4) and more locally at the catchment scale for the Upper Todd River Catchment (Chapter 5). In Chapters four and five I describe in detail the land tenure and use, land systems, climate soil, geology, topography, hydrology, vegetation and biodiversity of the Burt Plain bioregion and Upper Todd River Catchment. The bioregion contains some ephemeral watercourses, which are generally in fair to good condition, but are afforded little protection from a range of threatening processes, including grazing and trampling by feral animals and livestock and weed infestation. The major river systems occurring in the bioregion include parts of the Plenty, Hanson, Sandover and Lander Rivers. In the Upper Todd River Catchment the major watercourses Biodiversity conservation at the bioregional level are the Todd River and Station Creek, which exit the area via two narrow gaps in the low rocky hills on the southern boundary of the bioregion. The dominant geology can be summarised as plains and low rocky ranges of Pre-Cambrian granites on red earths. The bioregion has approximately 200 - 250 mm of summer rainfall, with rainfall occurring on 20 - 30 days per year. There is a high variability and range of temperatures, with an annual mean temperature of approximately 22-23°C. In Chapter six I consider a range of species found within the Burt Plain bioregion using existing survey data and techniques that enables the prediction of the spatial distribution of taxa. Using GLM and GAM models, Black-footed Rock- Wallaby (Petrogale lateralis), Spinifex Hopping Mouse (Notomys alexis) and Spencers Frog (Limnodynastes spenceri) were chosen for a more in-depth analysis. Environmental variables correlated with the presence of each species are then described and prediction maps showing the probability or likelihood of the presence of the species within the bioregion developed. In Chapter seven I examine the utility of radiometric data for wildlife habitat modelling. Statistical relationships are tested between the concentrations of the elements uranium, thorium and potassium and terrain characteristics such as position in the landscape, slope and aspect as well as other climatic variables. Radiometric data were found to be useful for developing statistical predictive Biodiversity conservation at the bioregional level models of six species: Red Kangaroo (Macropus rufus), Desert Dunnart (Sminthopsis youngsoni), Rabbit (Orcytolagus cuniculus), Brown Honeyeater (Lichmera indistincta), Little Spotted Snake (Suda punctata) and Southern Boobook (Ninox novaeseelandiae). I suggest that the utility of radiometric data for wildlife habitat modelling would appear significant and should be explored further using alternative quantitative modelling techniques and presence/ absence records for target faunal species. Predictions of species distributions may be useful for prioritising land acquisitions for reservation as well as in the future design of biological surveys. The thesis concludes with a synthesis of the major research findings, discussion of the limitations of the datasets available for the study, perspectives on management issues in the Burt Plain bioregion, and possible future research directions. It is important that purposefully-designed biological survey research be undertaken across the bioregions of the arid zone of Australia to enhance basic understanding of biodiversity patterns and their relationships to environmental heterogeneity and site-landscape level processes. Geospatial modelling techniques can assist such biodiversity survey and evaluation and make their conduct more cost-efficient and the inferences drawn from subsequent data analyses more powerful. This knowledge is required to contribute to the emergent concepts and theory of ecosystem dynamics and associated biodiversity patterns in arid Australia and, most significantly, to enhance the conservation and management of the unique biological complement and systems found in this region.

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Weaver, Haylee Jade, and haylee weaver@anu edu au. "BIODIVERSITY OF THE PARASITE FAUNA OF THE RODENT GENERA ZYZOMYS THOMAS, 1909 AND PSEUDOMYS GRAY, 1832 FROM NORTHERN AUSTRALIA." Central Queensland University. Dept. Molecular and Life Sciences, 2008. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20081005.153246.

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This study of the parasite fauna of five Australian rodents (Muridae: Hydromyinae: Conilurini) was undertaken to increase the knowledge of Australian parasite biodiversity. Trapping for Zyzomys argurus (Thomas, 1889), Pseudomys delicatulus (Gould, 1842), P. desertor Troughton, 1932, P. gracilicaudatus (Gould, 1845) and P. hermannsburgensis (Waite, 1896) (Rodentia: Muridae) was carried out at 16 locations in Queensland between 2004 to 2006. A total of 51 rats were captured and examined for parasites. In addition, 119 rats, from collections in the Queensland Museum and the University of Sydney, were examined. Finally, 57 samples of parasites collected from the above hosts and deposited at the Australian National Wildlife Collection (CSIRO) were identified. From these five rodent species, 15 species of ectoparasites and 17 species of endoparasites were recorded. Fifteen new host records and 14 new locality records were found. The ectoparasites comprised four species of Laelaps Koch, 1836 (Parasitiformes: Laelapidae), four species of chiggers (Acariformes: Trombiculidae), two species of fleas (Siphonaptera: Pulicidae, Pygiospyllidae) and two species of ticks (Parasitiformes: Ixodidae). Three new species of lice (Anoplura: Hoplopleuridae) were discovered. The 17 endoparasites, all helminths, comprised fourteen species of nematode and three species of cestode. There were 11 species of oxyurids (Nematoda: Oxyuridae, Heteroxynematidae), including 10 new species of Syphacia, two species of Odilia (Nematoda: Heligmonellidae), and one species of Nippostrongylus (Nematoda: Heligmonellidae). Three species of cestodes (Cestoda: Anoplocephalidae, Taeniidae, Davaineidae) were collected. There were no trematodes or acanthocephalans found in any of the rodents examined. No protistan parasites were found in tissue and blood samples taken from the rodents. The mean species diversity of parasites for each host rodent species was consistently low, with values of Simpsons Reciprocal Index ranging from 1.00 1.53. Possible factors contributing to this low diversity include habitat preferences, dietary ecology and social structure. There was no significant relationship found between host body weight and abundance of ectoparasites, or host body weight and species richness of helminths. The index of discrepancy (D) was used to evaluate the distribution of parasite species across host populations. Most parasites were found to have aggregated distributions within the host populations. The exception to this was two of the four species of laelapid mite, with values <5, indicating that they were common across host populations. The phylogenetic relationships of the Syphacia species occurring in the Australian bioregion were investigated using morphological characters. Relatively low resolution of the trees produced indicated that there may be a high degree of similarity between species. Two main clades were identified- a clade of genera of Syphaciini from Borneo was shown to be basal to the clade of species of Syphacia examined. Within the clade of the genus Syphacia, the new species identified in this study formed a single cluster on trees. There was no evidence, however, for strict coevolution of these worms and their hosts. Overall, the research presented here adds considerable knowledge to the previous paucity of information of the parasites of Australian native rodent species. This was achieved by contributing new host records, locality records and identifying and describing several new species. The relationships between conilurin rodents and their parasites suggests that coevolution plays a large part in the speciation of parasites, and that minimal host switching has occurred in the helminths of the conilurins of northern Australia.

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Leach, Elliot. "Monitoring the effects of climate change on the rainforest birds of eastern Australia." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/379569.

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Climate change will significantly affect avian biodiversity on a global scale. Increasing temperatures over the next century will lead to shifts in species distributions, alterations in the timing of breeding and migration, changes in morphology and shifts in genetic frequencies among avian populations. The global hotspots of avian diversity are found in mountainous rainforests, regions which may be difficult to access. Therefore, effective ways of monitoring rainforest bird assemblages are vital, for both ecologists and conservationists. This thesis addresses the challenge of monitoring the effects of climate change on rainforest bird assemblages. I used two methods, point counts and automated acoustic recording, to sample the rainforest birds occupying three elevational gradients in rainforests on the east coast of Australia. In doing so, I had the following aims: 1) to determine whether biodiversity data from automated acoustic recordings made using automated recording units (ARUs) was comparable to data generated using a traditional method (point counts), 2) to assess the ability of ARUs to monitor cryptic rainforest species for long time periods, 3) to identify birds that could be used as indicator species of elevation for the purpose of long-term climate change monitoring, and 4) to investigate the driving factors of bird species richness and abundance along elevational gradients in Australian rainforests. Existing studies showed contrasting results when comparing the effectiveness of traditional avian sampling methodologies with ARUs. To address this in an Australian rainforest context, we collected data on the birds of Eungella National Park in central Queensland over two sampling periods. We found that data from point counts and ARUs was broadly similar. On average, point counts detected more species than recordings of the same duration. The respective strengths and weaknesses of point counts and ARUs are complementary, and they should be used simultaneously in future biodiversity surveys. ARUs can sample remotely, simultaneously, and for long time periods. Using ARUs, we collected a year’s worth of data on two cryptic species inhabiting rainforest in north-eastern New South Wales. Bassian Thrush Zoothera lunulata and Russet-tailed Thrush Z. heinei are secretive inhabitants of wet forests on the eastern coast of Australia. We found that the two species had differential elevational preferences: Bassian Thrush preferred elevations above 900m asl, and Russet-tailed Thrush preferred elevations below 700m asl. Recordings of song indicated that Russet-tailed Thrush bred earlier than Bassian Thrush in 2015. This, along with the elevational preferences of the two species, may be related to temperature. The use of ARUs enabled us to quantify the elevational preferences and likely breeding times of these cryptic species. Populations of Bassian Thrush in north-eastern New South Wales and south-eastern Queensland are likely to decline with increasing temperatures. Upwards shifts in the elevational ranges of rainforest birds are expected due to increasing global temperatures. Identifying the current elevational distributions of indicator species has been suggested as one way of monitoring such upwards shifts. Previous research in our study region had identified indicator species among various invertebrate and plant taxa, but information on vertebrate indicators was lacking. Using data on the elevational preferences of birds collected over one year, we identified avian indicators of lowland and highland rainforest sites in north-eastern New South Wales. These indicators may be used to detect future shifts in species elevational preferences in the region. Previous research in tropical rainforests of the Wet Tropics identified temperature as an important driver of bird species’ distributions. There was a comparative lack of information for the subtropical rainforests of north-eastern New South Wales. Our data from elevational gradients in this region indicated that temperature was significantly positively correlated with both avian species richness and abundance. Species richness declined with elevation; there was no consistent elevational pattern in abundance. We found that species’ functional traits mediated their responses to the changes in environmental conditions along the gradient: large-bodied and small-bodied species are likely to be affected in different ways by increasing temperatures. My research has determined effective ways of monitoring the effects of climate change on rainforest bird assemblages. In doing so, I have also addressed major gaps in the knowledge of two relatively understudied biodiversity hotspots on the eastern coast of Australia. The baseline data presented in this thesis allows future researchers to detect changes in the avian biodiversity of the study regions, and represents a significant contribution to ornithology and climate change research in Australia and internationally.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Rule, Beau Brenton. "Ediacaran biodiversity : palaeoecological assessment of successive latest Proterozoic (Neoproterozoic) faunal assemblages in the Western Flinders Ranges, South Australia /." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09SB/09sbr9352.pdf.

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Lyons, Anita Marie. "Oil mallee plantings and arthropod biodiversity in the Western Australian wheatbelt : effects of host species, nutrition, and leaf chemistry." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/1620.

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Since European settlement, around 93% of the Western Australian wheatbelt has been cleared for agriculture, leading to a range of environmental problems, including erosion, salinity, and loss of biodiversity. Recently, oil mallees have been developed for use in the reduction and prevention of salinity, and in the production of oil, activated carbon, and electricity. While some work has been done on aspects of mallee ecology in order to maximize productivity, little is known about their usefulness as a source of biodiversity in natural and agricultural systems.This study concentrates on the canopy arthropod fauna of the mallees. While canopy research involving arthropods is common in tropical systems, there is limited information on temperate systems and still less relating to agro-forestry or conservation plantings in agricultural areas.Sampling was conducted in alleys of oil mallee vegetation and in remnant vegetation in the wheatbelt of Western Australia. Three mallee species: Eucalyptus polybractea, E. kochii subsp. borealis, and E. loxophleba subsp. lissophloia, and two native remnant species: Eucalyptus wandoo subsp. wandoo and E. astringens were used in the study. Trees were sampled for arthropods by canopy knockdown spraying in October 2005 and May 2006. Samples were sorted to the ordinal level in the laboratory. Coleoptera (beetle) specimens were identified to the species level. Leaf and soil samples were taken at each site and from each tree species in order to determine the levels of nutrition available to herbivorous arthropods. Leaves were also collected for terpenoid (essential oil) extraction and formylated phloroglucinol (sideroxylonal) analysis to determine the influence of leaf chemistry. Data were tested for homogeneity of variance and transformations were done where necessary. A range of statistical analyses including, analyses of variance, LSDs, coefficients of correlation, MDS ordinations, ANOSIM analysis, and the BEST procedure, were conducted on the data collected.It was determined that, for this study, chemical knockdown would be an ideal method for sampling such arthropods. A preliminary study examined the effect of repeated sampling of the same tree on canopy arthropod assemblages and found there was no effect of re-sampling on the ordinal level richness or total abundance of arthropods collected at the second sampling, six months later. As a consequence, we can be reasonably confident that the results in other sections of the thesis have not been confounded by the need to re-sample the same trees.The effect of oil mallee host species on canopy arthropod assemblages was examined. It was found that while there were minor differences in the presence or absence of some of the leaf blemishes recorded between species, with leaf folding being more prevalent on E. kochii and psyllids more common on E. loxophleba, there was no significant difference between the species in terms of ordinal richness or total abundance of arthropods. As there were very few differences observed between the three mallee species, it made it relatively simple to compare mallees generally with remnant vegetation. This was important, as mallees were treated as a single entity being compared to the two remnant species in other parts of the thesis.The ordinal richness and total abundance of canopy arthropods in two types of eucalypt vegetation, woodland eucalypts in remnant vegetation and mallee eucalypts in farm alley plantings was compared. Intuitively, we would expect native remnant vegetation to support a greater diversity of arthropods than any planted vegetation, simply by virtue of the native vegetation being in place for a longer period of time. The results of this study however, did not support this view. Arthropod richness and abundance were not significantly different between the tree species. Leaf blemishes and their associated sedentary arthropods also showed no significant differences between the species and overall very few differences between the mallee and remnant vegetation types were evident.The influence of major soil and leaf nutrients on arthropod assemblages, both in natural and planted eucalypt stands, were explored. It appears that arthropod abundance, in particular, is related to soil and leaf nutrient levels. There was, however, only limited evidence of increased arthropod ordinal richness in response to greater nutrient levels. Generally, high nutrient levels tended, instead, to reduce arthropod ordinal richness. Of the soil nutrients, phosphorus was the most influential, with high levels of phosphorus tending to relate to higher arthropod abundances. For leaf nutrients, phosphorus and nitrogen were important, with high levels of phosphorus being associated with lower ordinal richness, while high levels of leaf nitrogen were related to higher arthropod abundances. As high soil phosphorus and high leaf nitrogen tended to occur together, it is difficult to say whether one or the other is responsible for increases in arthropod abundance, though intuitively one would suggest that good soil nutrition led to enhanced plant quality, which in turn increased arthropod abundance.The role of leaf essential oils and other secondary plant compounds in determining arthropod abundance and ordinal richness was also examined. A number of secondary plant compounds were present in the host tree species tested, and there were wide variations in the levels of these compounds between the species tested. A range of relationships, including deterrent and attractant effects, were observed between arthropod assemblages and the various secondary plant compounds. Generally speaking, mallee species had high cineole and low pinene levels and remnant species had the opposite. Sideroxylonals showed no such pattern with vegetation type, being high in E. loxophleba and absent in the other mallee species. In terms of their influence on arthropods, the compounds varied in their effects. Pinene had a generally negative effect, while cineole had a generally positive one. Sideroxylonal, however, was more complicated in its effects as it had a negative effect on ordinal richness, but was positively correlated with Hemiptera numbers. This suggests that it is highly unlikely that any one of these compounds can explain the pattern of arthropod assemblages observed in isolation. It seems more probable that complex interactions between these chemicals cause changes in nutritional quality and palatability of foliage, influencing the feeding behaviour, development, distribution and abundance of herbivores, in turn affecting predator densities and feeding behaviour.The ways in which arthropod biodiversity may be influenced by the factors of host tree species, soil and plant nutrition and leaf chemistry were examined in more detail using the order Coleoptera as an example. Season of sampling was found to have an influence, with both beetle richness and abundance being higher at the first than the second sampling. Site, on the other hand, had very little influence. Of all the tree species, E. polybractea had both the highest beetle species richness, and high levels of beetle abundance. Strong similarities were apparent between beetle assemblages resident on the same tree species. No influence of soil or leaf nutrients on either beetle richness or abundance was observed. However, beetle abundance was found to have a negative relationship with leaf pinene. Cineole levels were lower in the remnant species (which tended to have similar assemblages), while pinene was high in E. loxophleba subsp. lissophloia and the remnant species. The other major leaf chemical examined, sideroxylonal had no significant impact on beetle richness or abundance. Statistical analysis selected cineole as the single factor best explaining the pattern of beetle assemblages observed, though this result should be treated with caution due to possible confounding of the results as a consequence of interaction between the factors.The broad aim of this research was to determine whether oil mallee plantings enhance arthropod biodiversity in agricultural landscapes. The results of this thesis show that oil mallees do support high levels of arthropod biodiversity. Overall, the mallees had a level of diversity, not dissimilar to that of high quality remnant vegetation. When planted in alleys across agricultural fields, they represent a significant change in the vegetative and architectural diversity of the landscape, and can have a positive influence on the environment by supporting beneficial arthropods and other native animals, reducing dryland salinity, and improving the aesthetics of the wheatbelt.Aside from their environmental credentials, oil mallees also provide the potential for farmers to make an income from something designed to benefit the environment. If oil mallee farming can be developed appropriately, it has the potential to benefit not only farmers and the environment, but the community of Western Australia as a whole.

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Molloy, Shaun. "Applying the principles of spatial modelling to the management of biodiversity in the fragmented landscapes of south-western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/870.

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Biodiversity conservation throughout the world is challenged by the impacts of a changing climate on fragmented landscapes. To mitigate these threats, conservation managers require models which can demonstrate the consequences of both negative impacts and management actions. This need can be addressed through spatial modelling applications. Unfortunately, throughout much of the world, spatial modelling is forgone, being seen as requiring skills and resources beyond the means of many conservation planners and managers. This thesis seeks to address this dilemma by delivering criteria for a successful modelling application and by providing case studies which demonstrate how appropriate modelling can be undertaken without highly specialised skills or prohibitively expensive software and equipment. In this way it facilitates the delivery of better targeted and, consequently more effective, management actions. For my case studies I have used the south-western corner of Australia as a demonstration landscape. This region is recognised internationally as a “biodiversity hotspot,” not only for the biological richness and uniqueness of species but also for the level of threat to which they are subject. Like many landscapes throughout the world, much or this region’s natural biota exists in fragmented, fragile and degraded patches and is therefore highly vulnerable to the anticipated impacts of anthropogenic global warming. In this thesis I have: 1) examined the principles of spatial modelling and reviewed how spatial modelling has been applied to conservation management in this region, 2) conducted examples of different forms of spatial modelling using actual regional conservation management issues, and 3) demonstrated how these examples can be incorporated into conservation management planning. My key findings are: Spatial modelling provides users with an opportunity to effectively test hypotheses, thereby informing the planning process and improving conservation outcomes. Where spatial modelling is omitted from the process, knowledge gaps are often addressed by the axiomatic and by assumption. This is contrary to the principles of effective adaptive management. Modelling tools are inherently more effective when selected for their capacity to meet a planning objective rather than where projects are tailored to meet a model’s capacity. The coordinated use of multiple tools can often provide a more robust understanding of the consequences impacts and mitigating actions. All tools and data sets used should be utilised with a clear and acknowledged understanding of their suitability, strengths and limitations. A wide range of spatial modelling tools (and data sets) are freely and readily available to conservation managers. Most of these come with excellent tutorials and support services. Data gaps can often be addressed through targeted field observations, obtained through complimentary planning processes, or synthesised from accessible data sets. There is a very large body of peer reviewed literature demonstrating means by which others have applied existing modelling tools, or developed tools themselves, to meet a wide range of applications. Accessing this literature is an excellent means of building spatial modelling capacity. New and improved tools, methodologies and data sets are constantly being developed. A failure to implement effective spatial modelling is becoming increasing difficult to justify.

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Williams, Matthew R. "Diversity of butterflies and day-flying moths in urban habitat fragments, south-western Australia." Thesis, Curtin University, 2009. http://hdl.handle.net/20.500.11937/1757.

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This study adapted and developed methods of assessing and modelling biodiversity of butterflies and day-flying moths in habitat fragments, and determined those factors affecting their presence, abundance and species richness in a sample of 46 isolated urban remnants in south-west Western Australia. The specific objectives were to: (i) assess the effectiveness of transect–based sampling to quantify the species richness of habitat fragments; (ii) examine patterns of species richness in habitat fragments and quantify the detectability of each species recorded; (iii) review and rationalize the methods used to fit species–area–habitat models; and (iv) model species incidence, abundance and total richness of butterflies in urban habitat fragments and determine implications and priorities for their conservation.These objectives were achieved and the principal findings of the research are: (i) The transect method provides an accurate assessment of butterfly species richness in isolates provided that the level of sampling (proportion of area surveyed) is adequate, that sufficient surveys are conducted during the flight season to ensure high levels of detectability, and that surveys are conducted at appropriate times and during suitable weather conditions. Although randomly placed transects are preferable, logistic constraints often dictate the use of existing pathways, roadsides or management tracks – which requires the use of longer transects but is more practical in urban remnants.(i) The transect method provides an accurate assessment of butterfly species richness in isolates provided that the level of sampling (proportion of area surveyed) is adequate, that sufficient surveys are conducted during the flight season to ensure high levels of detectability, and that surveys are conducted at appropriate times and during suitable weather conditions. Although randomly placed transects are preferable, logistic constraints often dictate the use of existing pathways, roadsides or management tracks – which requires the use of longer transects but is more practical in urban remnants.(iii) Almost a century of fitting species–area curves has failed to produce agreement on which function is the best model of the relationship. Many of the proposed functions are identical, special cases of others or have arisen from transcription errors. Empirical comparison of these functions requires methods suited to the distribution of species number such as the generalized linear model, method of maximum likelihood and the information-theoretic approach, and proper attention to covariates and their interactions.(iv) Site area and vegetation condition were the dominant determinants of the presence, abundance and total species richness of resident butterflies and day-active moths in 46 urban habitat fragments in south-west Western Australia. Larger sites with more high quality (undisturbed) vegetation favoured 16 of 20 native species and only one benefited from disturbance. A further nine species not sufficiently widespread or abundant to enable individual analysis were collectively more prevalent in larger sites. Resource quality and quantity dominated the patterns of site occupancy, and increased site connectivity did not favour any species – results consistent with habitat resources, not metapopulation effects, determining current distribution patterns. As expected, the presence of non-resident species was unaffected by site area. The total number of resident species at each site reflected the collective responses of the individual species: increasing with area and declining with vegetation disturbance. The effects of area and vegetation quality were not simply additive: disturbance had a far greater impact on small remnants. This interaction is inconsistent with the area per se hypothesis: in the absence of disturbance there was no evidence of a species–area effect.This study is the first comprehensive, quantitative assessment of the distribution and ecology of butterflies and day-flying moths in Australian urban habitat fragments and provides a baseline against which future changes in species distributions may be measured. The results have important implications for the conservation of butterflies and day-flying moths in the region. Maintenance of vegetation quality is of paramount importance and is vital in smaller remnants. Large remnants, being less susceptible to local extinctions, will be essential for the persistence of many species. Many functions have been proposed to model the species–area relationship but empirical comparisons have been hindered by methodological problems – this study conducted a re-examination of the relationship and presents an appropriate framework to compare functions. This study is also one of few to demonstrate and quantify the importance of interactions in explaining patterns of species richness and should stimulate future research into the importance of these effects.

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Liang, Weiguang, University of Western Sydney, of Science Technology and Environment College, and of Science Food and Horticulture School. "Impact of horticultural mineral oil and synthetic pesticides on arboreal and soil fauna biodiversity within citrus orchard ecosystems." THESIS_CSTE_SFH_Liang_W.xml, 2002. http://handle.uws.edu.au:8081/1959.7/121.

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The results of the 3-year project successfully indicated that petroleum-derived spray oils can be used for effective control of a range of citrus pests including citrus leafminer, Asiatic citrus psyllid, chaff scale, red scale, citrus red mite. The results suggested that it should be possible, through use of horticultural and agricultural mineral oils and enhanced natural enemy activity, to reduce the number of pesticide sprays applied annually in China from 14-16 sprays to significantly fewer sprays in most regions. The results are also valuable as references for the implementation of citrus integrated pest management programs in Australia and other citrus-growing countries. However, despite extensive use of PDSOs in citrus and other crops since the late 1800s, few studies have been undertaken to determine their disruptive effects on orchard ecosystems or to compare their effects with those of synthetic pesticides, and these studies are limited in their sc
Doctor of Philosophy (PhD)

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Williams, Matthew R. "Diversity of butterflies and day-flying moths in urban habitat fragments, south-western Australia." Curtin University of Technology, Department of Environmental Biology, 2009. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=129025.

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This study adapted and developed methods of assessing and modelling biodiversity of butterflies and day-flying moths in habitat fragments, and determined those factors affecting their presence, abundance and species richness in a sample of 46 isolated urban remnants in south-west Western Australia. The specific objectives were to: (i) assess the effectiveness of transect–based sampling to quantify the species richness of habitat fragments; (ii) examine patterns of species richness in habitat fragments and quantify the detectability of each species recorded; (iii) review and rationalize the methods used to fit species–area–habitat models; and (iv) model species incidence, abundance and total richness of butterflies in urban habitat fragments and determine implications and priorities for their conservation.
These objectives were achieved and the principal findings of the research are: (i) The transect method provides an accurate assessment of butterfly species richness in isolates provided that the level of sampling (proportion of area surveyed) is adequate, that sufficient surveys are conducted during the flight season to ensure high levels of detectability, and that surveys are conducted at appropriate times and during suitable weather conditions. Although randomly placed transects are preferable, logistic constraints often dictate the use of existing pathways, roadsides or management tracks – which requires the use of longer transects but is more practical in urban remnants.
(i) The transect method provides an accurate assessment of butterfly species richness in isolates provided that the level of sampling (proportion of area surveyed) is adequate, that sufficient surveys are conducted during the flight season to ensure high levels of detectability, and that surveys are conducted at appropriate times and during suitable weather conditions. Although randomly placed transects are preferable, logistic constraints often dictate the use of existing pathways, roadsides or management tracks – which requires the use of longer transects but is more practical in urban remnants.
(iii) Almost a century of fitting species–area curves has failed to produce agreement on which function is the best model of the relationship. Many of the proposed functions are identical, special cases of others or have arisen from transcription errors. Empirical comparison of these functions requires methods suited to the distribution of species number such as the generalized linear model, method of maximum likelihood and the information-theoretic approach, and proper attention to covariates and their interactions.
(iv) Site area and vegetation condition were the dominant determinants of the presence, abundance and total species richness of resident butterflies and day-active moths in 46 urban habitat fragments in south-west Western Australia. Larger sites with more high quality (undisturbed) vegetation favoured 16 of 20 native species and only one benefited from disturbance. A further nine species not sufficiently widespread or abundant to enable individual analysis were collectively more prevalent in larger sites. Resource quality and quantity dominated the patterns of site occupancy, and increased site connectivity did not favour any species – results consistent with habitat resources, not metapopulation effects, determining current distribution patterns. As expected, the presence of non-resident species was unaffected by site area. The total number of resident species at each site reflected the collective responses of the individual species: increasing with area and declining with vegetation disturbance. The effects of area and vegetation quality were not simply additive: disturbance had a far greater impact on small remnants. This interaction is inconsistent with the area per se hypothesis: in the absence of disturbance there was no evidence of a species–area effect.
This study is the first comprehensive, quantitative assessment of the distribution and ecology of butterflies and day-flying moths in Australian urban habitat fragments and provides a baseline against which future changes in species distributions may be measured. The results have important implications for the conservation of butterflies and day-flying moths in the region. Maintenance of vegetation quality is of paramount importance and is vital in smaller remnants. Large remnants, being less susceptible to local extinctions, will be essential for the persistence of many species. Many functions have been proposed to model the species–area relationship but empirical comparisons have been hindered by methodological problems – this study conducted a re-examination of the relationship and presents an appropriate framework to compare functions. This study is also one of few to demonstrate and quantify the importance of interactions in explaining patterns of species richness and should stimulate future research into the importance of these effects.

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McElhinny, Chris. "Quantifying stand structural complexity in woodland and dry sclerophyll forest, South-Eastern Australia /." View thesis entry in Australian Digital Theses Program, 2005. http://thesis.anu.edu.au/public/adt-ANU20060322.133914/index.html.

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Grimbacher, Peter Siegfried. "Beetle Assemblage Responses to Rainforest Deforestation and Reforestation in North-Eastern Australia." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/365285.

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Insects are well recognised as being the major contributor to global biodiversity, and for their critical involvement in many biotic interactions. Most of the insect diversity is found in tropical rainforests. However, these forests are threatened by high rates of clearing and the subsequent fragmentation of remaining habitat. The effects on biota, particularly insects, are poorly understood as are the mechanisms mediating faunal changes. Reforestation could potentially alleviate some of the deleterious effects of forest loss and fragmentation. However, because reforestation is a relatively new endeavour, it is little known just how much insect biodiversity can be supported by reforestation and what factors influence insect colonisation. These issues were investigated in the Atherton Tablelands of north-eastern Australia, a landscape whose rainforest has been heavily cleared and fragmented over the last 80 years, but is also the focus of reforestation efforts. To quantify the effects of rainforest loss and fragmentation, pasture sites were compared with small rainforest fragments, and with the edges and interiors of large rainforest fragments (24 sites in total). Sites with replanted rainforest (planted with a high diversity of plants) were also included. These varied in their age (2-17 yrs) and their distance (0-4.5 km) from existing rainforest (24 sites in total). Another set of reforested sites was also studied but these differed in their planting style (number of plant species, spacing etc). This second set of sites was located in two regions: the Atherton Tablelands (50 sites), and in the subtropics of eastern Australia (54 sites). At each site, beetle assemblages were surveyed using methods that sample beetles near the ground (four ground-based flight interception traps in the first set of sites and ten pitfall traps in the second set of sites), and then the assemblages among site-types were compared. Over 32,000 beetles were caught and identified to the level of family, and of these, 15,206 were identified further to the level of species. Very few beetle species were present in pasture, suggesting that converting rainforest into pasture has a very strong negative effect on beetle diversity and species composition. Irrespective of rainforest fragment size, beetle species composition in drier rainforest habitats was different from that of moister rainforest. Beetle species composition also differed between small remnants and interior rainforest: drier-associated species were more abundant in small remnants, whereas wetter-associated species were more abundant in interiors. This pattern can be best attributed to a fragmentation effect mediated by differences in microclimate. With the exception of differences between rainforest and pasture, these results were generally not observed among beetle assemblages identified to coarser taxonomic groups (family, feeding guild, and body size). Among replanted rainforest, older sites and those adjacent to rainforest had a more rainforest-like beetle species composition. However, even the closer and older sites had a substantially lower abundance and richness of rainforest-associated beetles than did rainforest. Age effects were generally stronger than distance effects. Beetle assemblage similarity to rainforest was more strongly correlated with structural similarity to rainforest than with site age or distance from rainforest. Thus the use of revegetation techniques which lead to more rainforest-like structural conditions appears to be of over-riding importance in catalysing the rapid acquisition of rainforest beetle assemblages in the initial stages of restoration. Nevertheless, not all beetle species were equally affected by the factors tested. Large-bodied beetle species (>5 mm) were more strongly influenced by distance than small-bodied species (<5 mm), suggesting that small-bodied species are better dispersers, and thus are amongst the first to colonise new habitats. Spatial ubiquity in rainforest was not a good predictor of a species' dispersal ability. Interestingly, fewer of the broader groups (family, feeding guild, and body size) showed the response to distance evident at the species level although they showed differences between reforested sites differing in age, and between reforested and reference site-types. Therefore, these results and those from the fragmentation study suggest that information at the species level is more sensitive to environmental change than data identified to a coarser level of taxonomy or grouped according to feeding ecology or body size. For the pitfall-trapped beetles in the second reforested site network, beetle assemblages in all styles of reforestation were intermediate in species composition between pasture and rainforest. The similarity of beetle assemblages to intact rainforest increased with the age and structural complexity of reforested sites, although again structural complexity appeared to be of overriding importance. This study has shown that even small patches of rainforest and reforested areas can support diverse rainforest-dependent beetle assemblages. A range of factors influence the development of beetle assemblages in reforested sites although not all species are equally affected. However, even structurally complex reforested sites cannot provide a short- or medium-term substitute for the retention of intact rainforest.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
Faculty of Environmental Studies
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Saraswati, Anandashila. "Swamp : walking the wetlands of the Swan Coastal Plain ; and with the exegesis, A walk in the anthropocene: homesickness and the walker-writer." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2012. https://ro.ecu.edu.au/theses/588.

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This project is comprised of a creative work and accompanying exegesis. The creative work is a collection of poetry which examines the history and ecology of the wetlands and river systems of the Swan Coastal Plain, and which utilises the practice of walking as a research methodology. For the creative practitioner walking reintroduces the body as a fundamental definer of experience, placing the investigation centrally in the corporeal self, using the physical senses as investigative tools of enquiry. As Rebecca Solnit comments in her history of walking, ‘exploring the world is one of the best ways of exploring the mind, and walking travels both terrains’ (Solnit, 2000, p. 13). The context for my poetic walking project Swamp, is a local and global environment undergoing an unprecedented loss of biodiversity, mainly due to the destruction of habitat and changes in climatic conditions (Reid, Partha Dasgupta, Robert M. May, A.H. Zakri, & Henk Simons, 2005, pp. 438-442). The loss of species and ecosystems that have been a part of our earth home results in the human experience of ‘homesickness’ — a longing for the home places that we have known and which have diminished or disappeared. Before the arrival of the British colonists in 1829, the Swan River and adjacent wetlands were an integral part of the seasonal food source for the original inhabitants, the Noongar (Bekle, 1981). In addition wetland places were, and are, deeply embedded in the spiritual and cultural life of the Noongar people of the Swan Coastal Plain (O'Connor, Quartermaine, & Bodney, 1989). In less than two hundred years since the establishment of the Swan River Colony (Western Australia), the lakes and rivers of the Swan Coastal Plain have undergone extreme changes, often resulting in complete draining and in-filling of wetland areas as the city and its suburbs spread beyond the original town limits. This re–engineering of the landscape has had a dramatic and detrimental impact upon biodiversity, water quality and the sense of place experienced by residents. Swamp is a project that has three main facets: a) a body of original poetry which interprets the historical relationship between the British, European, and Chinese newcomers to Noongar country, and the wetlands lakes of the Swan Coastal Plain. The poetry contained in this thesis is copyright to the author, Anandashila Saraswati (Nandi Chinna). b)An essay which contextualises the project within the sphere of walking art, psychogeography, and the philosophical idea of ‘Homesickness’. c) A website, www.swampwalking.com.au, which displays photographs documenting the walks I have carried out over the three year period of the project from February 2009 to February 2012. The exegetical part of this project looks at the notion of ‘homesickness’ as a philosophical condition that can be seen as a motivating force in the practice of writing on walking. I use Debord’s theory of the dérive as a starting point for my walking methodology and examine nostalgia within the Situationist International (Debord, 1958) and subsequent psychogeographical movements. I also investigate the role of homesickness in the work of other writers who walk and who write about their walking practice. Finally I discuss homesickness in the epoch of the Anthropocene (Crutzen & Schwägerl, 2011), the era in which the earth’s biosphere is characterised by human interventions which have changed the meteorological, geological and biological elements of our earth home. In the Anthropocene, the wilderness view of nature needs to be re-evaluated. I posit that walking is a way of reconnecting with the physical landscape and building relationships with small wilds that exist in our home places, and that writing about the walking allows these relationships and encounters to ripple out to readers, contributing to and enabling the development of an ethic of care for ecosystems and beings other than human.

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Prendergast, Kit Stasia. "Urban native bee assemblages and the impact of the introduced European honeybee on plant-pollinator networks in the southwest Australian biodiversity hotspot." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/84947.

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The thesis of Kit Prendergast addressed impacts of urbanisation and introduced honeybees on native bees in southwest Australia. Additionally, efficacy of bee survey methods were evaluated. The study found remnant bushland, with high proportions of native flora, was of greater importance for supporting native bee populations, species, and pollinator networks, compared with residential gardens. Honeybees occupied distinct positions in pollinator networks, and altered network properties, with context-dependent impacts on native bees.

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Adolphson, Honi M. "Acari (Mite) Abundance And Diversity In Soil And Litter Layers Of Eucalyptus Globulus Labill (Tasmanian bluegum) Plantations In Southwest Western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2000. https://ro.ecu.edu.au/theses/1542.

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With the increased planting of E. globulus monoculture plantations, concerns surround the impact these mass plantings will have on the soil environment and wider ecosystem. Soil and litter mites are the dominant saprophages of terrestrial ecosystems, contributing to decomposition processes through their comminution and grazing activities. Despite the importance of mites to decomposition processes, there have been no investigations to date of the litter and soil communities under these plantations within Australia. This study investigated the impact of Eucalyptus globulus subsp. globulus (Tasmanian bluegum) monoculture plantations on the diversity and abundance of the soil and litter acarine (mite) fauna. Mite communities under three 8 year-old E. globulus plantations sited on reclaimed pastureland were compared with an adjacent native E. marginata (jarrah) forest and a grazed pasture in the mediterranean-type region of southwest Western Australia. Sites were sampled in spring 1997 and new sites randomly selected in autumn 1998. Large seasona1 variations in abundance and diversity were found between the sampling periods of spring 1997 and autumn 1998, influenced considerably by soil moisture. Species richness was consistently higher in both the soil and litter layers under native jarrah forest, with the E. globulus plantations intermediate in species richness between the native forest and grazed pasture. A total of 114 mite species/morphospecies was recognized; 16 Mesostigmata, 52 Prostigmata, 45 Oribatida (Cryptostigmata) and 1Astigmata. Species diversity in the surface litter was higher under the native forest, reflecting the greater heterogeneity of the litter. Diversity in the underlying soil was similar for the native forest and E. globulus plantation, although there were considerable differences in species richness. Soil diversity in the pasture was very poor in comparison to the two forest systems, reflecting the absence of a litter layer and reduced niche dimensions. The monospecific E. globulus litter possibly reduced niche variety by simplifying the physical habitat and reducing the variety of resources available for the saprophagous fauna, of which the oribatid mites are a major component. Consequently, the number of families represented in the microphytophagous, phytophagous and predator functional groups under the E. globulus plantation may have been reduced. The most common oribatid families under the plantation were those often reported from disturbed habitats, Oppiidae and Tectocepheidae, and those common in many habitats, Oppiinae and Oppiellinae. An important management implication arising from this study is that these plantations would harbour a more diverse mite fauna if planted as a mixed tree stratum.

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Gimnich, France. "Molecular approaches to the assessment of biodiversity in limnic gastropods (Cerithioidea, Thiaridae) with perspectives on a Gondwanian origin." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2015. http://dx.doi.org/10.18452/17264.

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Da limnische Gastropoden eng an ihre isolierten aquatischen Habitate gebunden sind, bewahren sie Verbreitungsmuster über lange Perioden und stellen geeignete Modelle zur Rekonstruktion geographisch und klimatisch bedingter Veränderungen des Lebensraumes dar. Das Ziel dieser Arbeit besteht in der Rekonstruktion der Besiedlungsgeschichte des australischen Kontinents durch eine Familie Süßwassergastropoden (Thiaridae) unter Verwendung molekularer Marker (mitochondrialer und im Kerngenom basierter Genfragmente inklusive der AFLP-Technik). Viele der heute in Australien vorkommenden biotischen Elemente wurden als junge Einwanderer aus dem indo-malayischen Archipel eingestuft. Es werden jedoch immer mehr Fälle bekannt, die von diesem Standardszenario abweichen. Um zu testen, ob es sich bei Thiariden tatsächlich um Einwanderer aus dem Norden handelt, oder ob ihr Ursprung auf dem australischen Kontinent liegt, wurden die evolutionären Verwandtschaftsverhältnisse innerhalb der Familie, sowie ihre Position im phylogenetischen Stammbaum der Superfamilie Cerithioidea analysiert. Mit der Aufdeckung der stammesgeschichtlichen Beziehungen zu nicht-australischen Verwandten, durch Altersbestimmung der phylogenetischen Verzweigungen mittels „molekularer Uhr“ sowie der detaillierten Analyse der aktuellen Vorkommnisse und möglichen historischen Areale, konnte ein asiatischer Ursprung der Thiariden widerlegt werden. Ein Abriss hinsichtlich Dispersion und/oder Vikarianz ist hier vor dem Hintergrund der Rekonstruktion plattentektonischer Ereignisse dargestellt. Demnach hat die Besiedlung Asiens ihren Ausgang ursprünglich im australischen Raum genommen und der Kontinent wurde nicht wie bislang angenommen von Asien aus besiedelt. Mit der Aufdeckung eines gondwanischen Ursprungs repräsentieren Thiariden ein vielversprechendes Modellsystem in der Speziationsforschung, welches Einblicke in die Dynamik der Mechanismen der Artbildung unter dem Einfluss von klimatischen Veränderungen ermöglicht.
Due to their limited potential of dispersal and habitat fidelity, limnic gastropods tend to preserve distribution patterns over long periods of time and are suitable organisms in biogeographical research. In this thesis intensive investigations into the phylogeography of Australian freshwater snails are provided, presenting the first molecular study of the Thiaridae (Caenogastropoda: Cerithioidea) based on DNA sequence markers and amplified fragment length polymorphisms. The aim of this study is to determine the historical events that may have influenced their presence on the Australian continent. In general, the origin of Australian freshwater faunal elements and the directionality and timing of colonizations are still controversial. Conventionally, many biotic elements found in Australia today are considered to be recent invaders from the Indo-Malay archipelago but more and more cases have become known that deviate from this standard scenario. In order to test whether the thiarids represent recent invaders or if they originated on the Australian continent, the evolutionary relationships within the family as well as its phylogenetic position in the superfamily Cerithioidea is analysed. A molecular clock approach is applied so that the dispersal events can be related to historical tectonical changes. By comparison of the molecular phylogenies, as well as the distributional data, the fossil record and divergence date estimates in conjunction with the excellent record of Earth history the long-held view that the thiarid fauna is an appendage to the southeast Asian biota can be rejected. Instead, an Australian continental, i.e. East-Gondwanian origin is found to be the most parsimonious explanation of the present distribution. With their now assumed long history on the continent, thiarids represent an important model system in speciation research which provides details of the dynamics of the underlying mechanisms of speciation under the influence of climate change.

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Moon, Desiree L. "A Study of the Spatial Dynamics of some Introduced Avian Species in the Southwest Region of Western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/690.

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The Southwest region of Western Australia is a recognised ‘biodiversity hotspot’, as it possesses high levels of biodiversity and endemism; it also holds a number of species threatened by habitat loss. The arrival of Europeans in the region wrought major changes on the natural landscape. Extensive tracts of bushland were cleared for housing, infrastructure, forestry, farming, and mining. Another challenge to regional biodiversity was the spread of exotic plants and animals (including birds); the latter provide the focus for the present study. The research examines four bird species that colonised the Southwest region following European settlement: Australian White Ibis (Threskiornis molucca); Spotted Dove (Streptopelia chinensis); Laughing Dove (S. senegalensis) and Laughing Kookaburra (Dacelo novaeguineae). The study examines how the feeding and breeding ecology of the species influenced colonisation success and dispersal, specifically in relation to geographic i.e. climate and anthropogenic (e.g. landuse) features of the region. Each of these species has been identified as a ‘generalist’ feeder, with flexible ecological needs. The species have been able to adapt their food preferences and way of life to living in proximity to human settlements. It appears that each utilised resources made available through human endeavour and activities. It appears that the most rapid spread of invaders occurs in areas of modified habitat, in which the proportion covered by natural ecosystems has declined: i.e. in urban areas, pastoral lands and agricultural areas, although conserved natural habitats have also been invaded. The results indicate clear associations between the extent of colonisation success in the first wave of dispersal, and anthropogenic phenomena. Such is evidenced by the range expansion of Australian White Ibis into coastal urban areas, within which foraging success is assisted by access to alternative food sources and roost sites; whereas the species’ movement inland is linked to habitats associated with dairy farming and cattle production. However, the biology of each species and the extent of its ecological flexibility are also influencing factors, as attested by the wide-spread dispersal of the Laughing Kookaburra throughout the study area. This species possesses physiological features that give it an energy advantage over other species and it possesses social behaviours which offer further ecological advantages. Although it is a combination of factors: the biological attributes of the species (which define the ecological aspects of its survival), the geographical features of the adopted landscape, and the impact of human imprint upon that landscape that affect the process of biological invasion, the outcomes are specific to each species. This is shown in the development of markedly different patterns of dispersal, as between the two Streptopelia doves, despite their arriving in the study area under (approximately) the same conditions, and sharing almost identical ecological profiles. As, despite being released into rural areas, the Spotted Dove retained a localised, mainly urban, population, whilst the Laughing Dove has become spread across both urban and rural environments. This may be due to differences in the ability of each species to tolerate dryland conditions, which appear to better suit the Laughing Dove, perhaps due to similarities in climate between the adopted range and the areas from which it originates. It is felt that the study has augmented existing knowledge of biological invasion events in the study area, and contributed towards a greater understanding of biological invasion phenomena, particularly those associated with wheat production, processing, and transport. The study design incorporated Geographic Information Systems (GIS) technology as a means of processing large volumes of historical data. The methodology developed for the study could be adapted to other species, regions and eras, provided sufficient data are available. It produces temporal snapshots of changes in distributions, which can be considered in relation to changes in climate conditions and landuse practices.

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Tucker, David Ian. "The assessment of ecological condition in south-east Queensland, Australia: An evaluation of reliability across variable environments and surrogate efficacy for biodiversity values." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/94285/1/David_Tucker_Thesis.pdf.

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Multimetric ecological condition assessment has become an important biodiversity management tool. This study was the first to examine the reliability of these ecological surrogates across variable environments, and the implications for surrogate efficacy. It was demonstrated that through strategic application and design of the multimetric ecological condition index, the effects of environmental gradients and disturbance regimes can be mitigated, and that ecological condition assessment may serve as a scientifically rigorous approach for conservation planning.

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Barnes, Peter Brendan. "Environmental impacts and the ecology of sponges and ascidians in south-eastern Australian coastal lakes and lagoons." Department of Biological Sciences - Faculty of Science, 2009. http://ro.uow.edu.au/theses/849.

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Estuaries worldwide are under threat from urbanisation and development and will need effective management for their successful conservation. Coastal lakes and lagoons have been identified as one of the estuary types most susceptible to human impacts largely because of their isolated nature and slow flushing times. Management of estuaries will be most effective when based on a sound scientific understanding of the patterns of distribution, biology and ecology over the full range of biodiversity of these systems, however, such an understanding is lacking for many systems and many taxa. Studies of sponges and ascidians in coastal lakes and lagoons are rare compared to other taxa, particularly in the southern hemisphere. This study represents the first detailed scientific investigation of the ecology of sponges and ascidian in coastal lakes and lagoons of southeastern Australia. Consequently, a large part of this thesis was devoted to quantifying basic patterns of distribution. I started with a pilot study to develop an effective sampling design, followed by large-scale comparisons among different types of lake, comparisons among habitats within lakes and an environmental impact study. I concluded with a manipulative experiment to examine processes responsible for smallscale patterns of distribution of sponges in seagrass meadows.In the pilot study, distributions of sponges and ascidians were quantified at a hierarchy of three spatial scales in each of two coastal lakes. Nested analyses of variance were then used to identify spatial scales at which variation was significant. Most sponges and ascidians were very patchily distributed at a range of spatial scales from 10s of metres up to 100s of kilometres. Unlike other published examples of cost– benefit analyses, very few taxa were widespread over the larger spatial scales. Cost– benefit analyses done to determine the optimal sampling design revealed inclusion of patchily distributed taxa in analyses improved the overall precision of sampling for comparisons of assemblages among lakes.Large-scale comparisons of assemblages of sponges and ascidians were made among lakes of different size (big versus small), opening regime (mostly open to the ocean versus mostly closed) and level of environmental modification (extensively modified versus more pristine). Similar to other taxa studied in coastal lakes, in general there were more species in lakes mostly open to the ocean compared to the mostly closed lakes, and importantly, no sponges and only one species of ascidian was found in the small closed lakes. There also appeared to be an effect of the level of modification of a lake with relatively smaller abundances of ascidians in extensively modified lakes, and a complete absence of sponges from one of the extensively modified lakes.Habitat-associated patterns were examined at smaller spatial scales by comparing the distributions of sponges and ascidians with the species composition and percentage cover of seagrass and macroalgae within two lakes; St Georges Basin and Wallis Lake. Several patterns of association were observed, but these varied among species of sponge and ascidian. In St Georges Basin, the most common sponge, Aplysinella cf. rhax and the native ascidian Pyura stolonifera were positively correlated with the seagrass, Posidonia australis. In contrast, the introduced ascidian, Styela plicata was more abundant in areas dominated by the seagrass, Zostera capricorni. In Wallis Lake, sponges were most diverse and some species most abundant in large beds of the macroalga, Lamprothamnion sp., while other sponges were found only on the holdfasts of brown macroalgae. In both lakes, sponges were generally less common in areas dominated by dense meadows of the seagrass, Zostera capricorni.Among the many anthropogenic impacts threatening the ecology of coastal lakes, the discharge of cooling water from coal-fired power stations represents an almost ideal case study from which to develop appropriate sampling regimes for detecting impacts on sponges and ascidians. Using reference locations both within and outside Lake Macquarie which has two cooling water outlets, I found assemblages of sponges and ascidians were often more diverse, more abundant and less temporally variable near to the outlets compared to reference locations.Based on the observation that the sponge, Suberites sp. which contains photosynthetic symbionts was absent from meadows of dense Zostera capricorni, I used in situ manipulative experiments in Smiths Lake to investigate processes which maybe affecting their distribution. Individual Suberites sp. were shaded, had water flow reduced and were transplanted into areas of dense Z. capricorni. There were no measurable short-term effects of shading or reduced water flow, but transplanted sponges were quickly eaten and I concluded predation by fish was likely to be a key process determining small-scale patterns of distribution of Suberites sp. in seagrass meadows. This result was in stark contrast to the majority of previous studies of the effects of seagrass habitat complexity on predation which have found predation to decrease with increasing density or complexity.In conclusion, I have sought to provide sound scientific information to aid in the management of these systems. A simple, but nevertheless key finding was that sponges and ascidians are indeed present and widespread in coastal lakes and lagoons of southeastern Australia and should not be continually overlooked in the management and conservation of these systems. Conservation will be complex and requires an understanding of environmental impacts and the consequences of management on the full range of biodiversity. The distributions of sponges and ascidians at large ‘lakewide’ scales appear to behave similarly to other taxa. Management strategies which change the characteristics of a lake at these large spatial scales such as artificial openings of entrances could therefore be predicted to have similar effects across a range of taxa including sponges and ascidians. In contrast, at smaller spatial scales such as the complexity of seagrass meadows, some species of sponges and ascidians may behave very differently from other taxa. At present, our understanding of these naturally variable and complex systems is incomplete and will require ongoing scientific investigation to identify natural patterns of distribution, environmental impacts, important natural processes and the ecological consequences of management strategies.

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McQuillan, Lea. "Species richness, density and cover of sponge assemblages on temperate reefs off Perth, Western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2006. https://ro.ecu.edu.au/theses/359.

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Sponges were the dominant faunal benthic group, occupying 30 -50% of the limestone reef surface and displaying high diversity (>240 sponge species) on subtidal temperate reefs off Perth, Western Australia. Despite this high diversity there was little variation in composition among the six different sites sampled. However, there was within-site heterogeneity of sponge assemblages which has been ascribed to small-scale variation in light and sedimentation/abrasion rates. Differences in sponge assemblages were also detected between sampling times, species richness and sponge density were higher in winter compared to summer, whereas, sponge cover was higher in summer compared to winter. The results suggest that the growth and development of juveniles or annuals may have been adversely affected by the harsh conditions of winter. The higher temperatures in summer appeared to promote growth and reproduction of sponges. Rapid assessment techniques have been proposed to look for patterns in biodiversity in conservation biology studies, when detailed routine surveys are not feasible. Two rapid assessment techniques were assessed, firstly examining the dominant sponge species; and secondly aggregating the sponge species to order level. The results of two rapid assessment techniques were promising if comparing sponge assemblages across habitats. If the aim was to assess sponge assemblages across sites, neither rapid assessment technique showed the same results compared to species level data. The general conclusion for subtidal temperate reef sponge assemblages within Marmion Lagoon is that there is substantial loss of information for spatial comparisons when aggregating species to order level or using only the dominant sponges. What was found was that the two levels failed to detect differences among sites which were found in the species level data analyses, but all three analyses gave the same results for habitat data. In Western Australia only a few studies on sponges have been undertaken along the extensive coastline (12,500 km long). Previous sponge research in Western Australia occurred predominately as a result of taxonomic collections from expeditions undertaken in the 19th and early 201 h centuries. This study has described the 43 dominant sponge species that were found at six different sites on subtidal temperate reefs in Marmion Lagoon, Western Australia. Sponges were the dominant fauna found at most of the research sites off this coastal Perth location and included many species from a range of orders and families. Most of the species found occurred in sciaphilic (shade-loving) habitats. Only a few species occurred in full light conditions on the reef flats. This study documented 243 sponge species from subtidal limestone reefs between 8-12 metres in depth within the Lagoon. These 243 species comprised 197 siliceous sponges (Class Demospongiae) and 46 calcareous sponges (Class Calcarea) and were identified to at least order. Eighteen were identified to order, 88 to family, 35 to genus and 56 to species level. Approximately 30% of the species recorded here are possibly new to science.

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Smith, Lia. "Biodiversity monitoring using environmental DNA: Can it detect all fish species in a waterbody and is it cost effective for routine monitoring?" Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2017. https://ro.ecu.edu.au/theses/1985.

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The challenges associated with environmental monitoring such as the impact on the environment and the financial costs are problems we face when trying to conserve freshwater systems around the world. The need for precise and accurate results that are cost effective is important so that we can achieve our conservation goals. The overall aim of this study was to explore Next-Generation - metabarcoding for the detection of feral and native freshwater fish species based on the DNA shed by individual organisms into the water column. Cytochrome c oxidase I (COI) primers were developed for this study using DNA from six freshwater species expected to be found in the waterbody. These primers, along with 16S rRNA (16S) primers, were assessed to ensure that the molecular method was robust and suitable for use in the field. Along with the cost effectiveness of the molecular method when compared to the more traditional surveying method of Fyke net surveying. This study comprised development of field and lab protocols for the detection of freshwater fish species in a lentic system. Both the COI and 16S primer sets showed results that were comparable to previous Fyke net surveys, though both primer sets detected species that the other did not. Further qPCR analysis showed that there were differences in detection for both primers for each of the species. The molecular surveying of the waterbody has been proven sensitive enough to detect Maccullochella peelii. This species has a very low abundance in the waterbody (believed to be n=1) so these results suggest that this method can be used to target low abundance species. The outcome of this study highlighted the need for multi-location sampling within a waterbody as increasing the number of locations sampled, led to an increase in the number of species detected. Along with the multi-location sampling, it was also important to sample throughout the year to account for seasonal variability. The eDNA study emphasized the importance of having knowledge of both the ecology and the biology of the species targeted so that a robust monitoring method can be implemented. As well as comparing the apparent accuracy of Fyke netting and the eDNA approach in the study waterbody, a cost benefit analysis comparing the relative costs of multiplex DNA surveying, single species molecular surveying, and Fyke net surveying was undertaken. Molecular environmental surveying was found to be a cost effective method for monitoring, as the analysis suggested single species monitoring would break even after only 95 waterbodies were surveyed, and multiplex surveying would break even after 145 waterbodies, under the proposed scenario. The cost benefit analysis explored the costs associated with all three methods, including lab set up costs, along with the number of waterbodies that could be surveyed on both a weekly and yearly basis.

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Taukulis, Fiona E. "Diatom communities in lakes and streams of varying salinity from south-west Western Australia : distribution and predictability." Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/2164.

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The distribution pattern of diatoms from lakes and streams of varying salinity in the south-west of Western Australia was investigated. A total of 95 water bodies were sampled and separated into freshwater (<3 ppt), hyposaline (3-20 ppt), mesosaline (20-50 ppt) and hypersaline (>50 ppt). The south-west and specifically the inland wheatbelt region has been severely influenced by secondary salinisation, due to clearing of native vegetation for agriculture. There has been little research on diatom communities from salt-affected systems, with this data providing the basis for the development of an inference model based on species optima and tolerance limits to salinity.Physico-chemical variables measured from the study sites were collated and assessed. Salinity ranged from freshwater (0.04) to hypersaline (156.80 ppt), and pH ranged from acidic (2.90) to alkaline (10.51). Dissolved oxygen levels were recorded from 1.11 to 18.67 mgL[superscript]-1, water temperature from 6.30 to 28.10 ºC and peripheral vegetation scores from 1 (little or no cover) to 5 (dense cover). Analysis of variance (ANOVA) showed that salinities were significantly higher in standing waters located further inland, compared to flowing waters in high rainfall areas. Hypersaline wetlands displayed significantly lower dissolved oxygen levels, higher water temperatures and reduced peripheral vegetation, compared to freshwaters. The pH of hypersaline sites was also significantly lower, associated with surrounding land use or underlying geology. The data collected provides important baseline information, with implications for aquatic biota.The community structure of diatoms in relation to varying salinity concentration was explored. An artificial substrate collector (JJ periphytometer) was used to standardise sampling and ensure diatom assemblages were representative of ambient water quality. A total of 217 taxa were identified with the highest diversity observed in freshwater sites (up to 33 species), and limited to less than 15 in hypersaline waters. According to BIOENV, salinity was the key factor influencing diatom community structure. SIMPER analysis found a number of discriminating taxa between salinity ranges, specifically between assemblages from freshwater and hypersaline sites. Taxa such as Achnanthidium minutissimum and Gomphonema parvulum were indicative of freshwaters. In comparison, Amphora coffeaeformis and Nitzschia ovalis were associated with hypersaline water bodies.Diatom community structure was also examined from 20 hypersaline wetlands in the wheatbelt region with varying pH. Characteristic taxa including Amphora coffeaeformis, Hantzschia sp. aff. baltica and Nitzschia ovalis showed a wide tolerance to salinity and pH, or hypersaline acidic conditions. BIOENV analysis found there were no observable differences between diatom assemblages in relation to salinities above 50 ppt and that pH was highly correlated to species composition. The increasing occurrence of acid saline lakes is of concern and is most likely attributable to deep drainage practices and continued use of fertilisers in agricultural areas.A diatom-based transfer function was developed from the south-west dataset, to document species optima and tolerance limits to salinity. CCA analysis showed that salinity accounted for a significant and independent amount of variation in the diatom data enabling an inference model to be derived. The most successful model was generated using tolerance-downweighted weighted averaging, with a high coefficient of determination and low prediction errors that remained high after jackknifing. The optima of freshwater diatoms were similar to those reported from other regions of the world, although the optima of hypersaline species tended to be higher. Comparatively, the model performed very well, with the potential to be applied in future paleolimnological studies.In conclusion, this study has shown diatoms to be effective biomonitoring tools, providing the basis for future sampling strategies that assess the biodiversity of salt-affected water bodies in Western Australia. Potential indicator species from different salinity ranges were identified and the sensitivity of diatoms allowed for the development of a statistically robust inference model for the south-west. The reported optima and tolerance limits of important taxa may be further explored to evaluate the success of remediation measures implemented for secondary salinised systems in this region.

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McElhinny, Chris, and chris mcelhinny@anu edu au. "Quantifying stand structural complexity in woodland and dry Sclerophyll Forest, South-Eastern Australia." The Australian National University. Centre for Resource and Environmental Studies, 2005. http://thesis.anu.edu.au./public/adt-ANU20060322.133914.

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In this thesis I present and test a methodology for developing a stand scale index of structural complexity. If properly designed such an index can act as a summary variable for a larger set of stand structural attributes, providing a means of ranking stands in terms of their structural complexity, and by association, their biodiversity and vegetation condition. This type of index can also facilitate the use of alternative policy instruments for biodiversity conservation, such as mitigation banking, auctions and offsets, that rely on a common currency the index value that can be compared or traded between sites. My intention was to establish a clear and documentable methodology for developing a stand scale index of structural complexity, and to test this methodology using data from real stands.¶ As a starting point, I reviewed the literature concerning forest and woodland structure and found there was no clear definition of stand structural complexity, or definitive suite of structural attributes for characterising it. To address this issue, I defined stand structural complexity as a combined measure of the number of different structural attributes present in a stand, and the relative abundance of each of these attributes. This was analogous to approaches that have quantified diversity in terms of the abundance and richness of elements. It was also concluded from the review, that stand structural complexity should be viewed as a relative, rather than absolute concept, because the potential levels of different structural attributes are bound within certain limits determined by the inherent characteristics of the site in question, and the biota of the particular community will have evolved to reflect this range of variation. This implied that vegetation communities with naturally simple structures should have the potential to achieve high scores on an index of structural complexity.¶ I proposed the following five-stage methodology for developing an index of stand structural complexity: 1. Establish a comprehensive suite of stand structural attributes as a starting point for developing the index, by reviewing studies in which there is an established relationship between elements of biodiversity and structural attributes. 2. Develop a measurement system for quantifying the different attributes included in the comprehensive suite. 3. Use this measurement system to collect data from a representative set of stands across the range of vegetation condition (highly modified to unmodified) and developmental stages (regrowth to oldgrowth) occurring in the vegetation communities in which the index is intended to operate. 4. Identify a core set of structural attributes from an analysis of these data. 5. Combine the core attributes in a simple additive index, in which attributes are scored relative to their observed levels in each vegetation community.¶ Stage one of this methodology was addressed by reviewing a representative sample of the literature concerning fauna habitat relationships in temperate Australian forests and woodlands. This review identified fifty-five studies in south-east and south-west Australia, in which the presence or abundance of different fauna were significantly (p<0.05) associated with vegetation structural attributes. The majority of these studies concerned bird, arboreal mammal, and ground mammal habitat requirements, with relatively fewer studies addressing the habitat requirements of reptiles, invertebrates, bats or amphibians. Thirty four key structural attributes were identified from these fifty-five studies, by grouping similar attributes, and then representing each group with a single generic attribute. This set, in combination with structural attributes identified in the earlier review, provided the basis for developing an operational set of stand level attributes for the collection of data from study sites.¶ To address stages two and three of the methodology, data were collected from one woodland community Yellow Box-Red Gum (E. melliodora-E. Blakelyi ) and two dry sclerophyll forest communities Broadleaved Peppermint-Brittle Gum (E. dives-E. mannifera ), Scribbly Gum-Red Stringybark (E. rossii E. macrorhyncha ) in a 15,000 km2 study area in the South eastern Highlands Bioregion of Australia. A representative set of 48 sites was established within this study area, by identifying 24 strata, on the basis of the three vegetation communities, two catchments, two levels of rainfall and two levels of condition, and then locating two sites (replicates) within each stratum. At each site, three plots were systematically established, to provide an unbiased estimate of stand level means for 75 different structural attributes.¶ I applied a three-stage analysis to identify a core set of attributes from these data. The first stage a preliminary analysis indicated that the 48 study sites represented a broad range of condition, and that the two dry sclerophyll communities could be treated as a single community, which was structurally distinct from the woodland community. In the second stage of the analysis, thirteen core attributes were dentified using the criteria that a core attribute should:¶ 1. Be either, evenly or approximately normally distributed amongst study sites; 2. Distinguish between woodland and dry sclerophyll communities; 3. Function as a surrogate for other attributes; 4. Be efficient to measure in the field. The core attributes were: Vegetation cover <0.5m Vegetation cover 0.5-6.0m; Perennial species richness; Lifeform richness; Stand basal area of live trees; Quadratic mean diameter of live stems; ln(number of regenerating stems per ha+1); ln(number of hollow bearing trees per ha+1);ln(number of dead trees per ha+1);sqrt(number of live stems per ha >40cm dbh); sqrt(total log length per ha); sqrt(total largelog length per ha); Litter dry weight per ha. This analysis also demonstrated that the thirteen core attributes could be modelled as continuous variables, and that these variables were indicative of the scale at which the different attributes operated.¶ In the third and final stage of the analysis, Principal Components Analysis was used to test for redundancy amongst the core attributes. Although this analysis highlighted six groupings, within which attributes were correlated to some degree, these relationships were not considered sufficiently robust to justify reducing the number of core attributes.¶ The thirteen core attributes were combined in a simple additive index, in which, each attribute accounted for 10 points in a total index value of 130. Attributes were rescaled as a score from 0-10, using equations that modelled attribute score as a function of the raw attribute data. This maintained a high correlation (r > 0.97, p< 0.0001) between attribute scores and the original attribute data. Sensitivity analysis indicated that the index was not sensitive to attribute weightings, and on this basis attributes carried equal weight. In this form my index was straightforward to apply, and approximately normally distributed amongst study sites.¶ I demonstrated the practical application of the index in a user-friendly spreadsheet, designed to allow landowners and managers to assess the condition of their vegetation, and to identify management options. This spreadsheet calculated an index score from field data, and then used this score to rank the site relative to a set of reference sites. This added a regional context to the operation of the index, and is a potentially useful tool for identifying sites of high conservation value, or for identifying sites where management actions have maintained vegetation quality. The spreadsheet also incorporated the option of calculating an index score using a subset of attributes, and provided a measure of the uncertainty associated with this score.¶ I compared the proposed index with five prominent indices used to quantify vegetation condition or habitat value in temperate Australian ecosystems. These were: Newsome and Catlings (1979) Habitat Complexity Score, Watson et al.s (2001) Habitat Complexity Score, the Site Condition Score component of the Habitat Hectares Index of Parkes et al. (2003), the Vegetation Condition Score component of the Biodiversity Benefits Index of Oliver and Parkes (2003), and the Vegetation Condition Score component of the BioMetric Assessment Tool of Gibbons et al. (2004). I found that my index differentiated between study sites better than each of these indices. However, resource and time constraints precluded the use of a new and independent data set for this testing, so that the superior performance of my index must be interpreted cautiously.¶ As a group, the five indices I tested contained attributes describing compositional diversity, coarse woody debris, regeneration, large trees and hollow trees these were attributes that I also identified as core ones. However, unlike these indices, I quantified weeds indirectly through their effect on indigenous plant diversity, I included the contribution of non-indigenous species to vegetation cover and did not apply a discount to this contribution, I limited the direct assessment of regeneration to long-lived overstorey species, I used stand basal area as a surrogate for canopy cover, I quantified litter in terms of biomass (dry weight) rather than cover, and I included the additional attributes of quadratic mean diameter and the number of dead trees.¶ I also concluded that Parkes et al. (2003), Oliver and Parkes (2003), and Gibbons et al. (2004), misapplied the concept of benchmarking, by characterising attributes in terms of a benchmark range or average level. This ignored processes that underpin variation at the stand level, such as the increased development of some attributes at particular successional stages, and the fact that attributes can respond differently to disturbance agents. It also produced indices that were not particularly sensitive to the differences in attribute levels occurring between stands. I suggested that a more appropriate application of benchmarking would be at the overarching level of stand structural complexity, using a metric such as the index developed in this thesis. These benchmarks could reflect observed levels of structural complexity in unmodified natural stands at different successional stages, or thresholds for structural complexity at which a wide range of biota are present, and would define useful goals for guiding on-ground management.

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Nakamura, Akihiro. "Development of Soil and Litter Arthropod Assemblages in Rainforest Restoration." Thesis, Griffith University, 2008. http://hdl.handle.net/10072/367553.

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Broadscale forest clearance is a major human-induced disturbance with devastating consequences for biodiversity. With a rise in public awareness of biodiversity, the last few decades have seen an increasing number of reforestation activities aimed at recreating natural habitat. To date, research on the outcomes of reforestation for biodiversity have mostly focused upon the recovery of vegetation structure and composition, with relatively little attention being paid to the recovery of fauna, especially invertebrates. Arthropods inhabiting soil and leaf litter constitute a considerable proportion of the biomass and diversity of a given faunal community, and exhibit strong associations with ecological functioning (i.e. soil formation, decomposition). The recovery of soil and litter arthropods in restored landscapes is therefore important, not only for the recovery of biodiversity but also for the re-development of a functioning ecosystem, a goal of most types of reforestation programs. However, we know little about the patterns of development of arthropod assemblages in reforested landscapes or the mechanisms underpinning any such patterns. The broad objective of this study was to investigate the effects of selected factors on the colonisation patterns of restored rainforest patches by soil and leaf litter arthropods. Criteria for selecting factors for study included their potential influence on the development of arthropod assemblages and their potential for manipulation by restoration practitioners. The study was conducted on the Blackall Range near Maleny, a mid-elevation (250-530 m a.s.l.) basaltic plateau in subtropical eastern Australia (26°S, 152°E). The plateau supported subtropical rainforest until European settlement in the 19th century, when most of the rainforest was cleared for pasture. The factors selected for study, in relation to the colonisation of restored habitat patches by soil and litter arthropods, were as follows: 1. the isolation of restored habitat patches from remnant forest; 2. the efficacy of inoculation (re-introduction of rainforest soil and litter arthropods) to restored habitat patches; 3. the quality and quantity of substrate (i.e. mulch) used during the initial stages of rainforest restoration; 4. the degree of shading and depth of substrate, and their interaction; and, 5. the short- and longer-term impacts of glyphosate herbicide on arthropod assemblages. To test explicitly the effects of these factors on arthropod colonisation of restored habitat patches, an experimental approach was adopted in this study. The first four factors were addressed by means of a manipulative field experiment. Small-scale habitat patches were created by adding sterilised mulch to an area previously treated with glyphosate herbicide, and covered with shadecloth, to simulate various conditions of forest restoration which may be experienced by colonising arthropods. In order to test for the impacts of a glyphosate herbicide on rainforest arthropods, I carried out a separate field experiment in which experimental patches were established within remnant rainforests. The experimental approach adopted in this study allowed for the construction of replicated units, while controlling for extraneous factors (e.g. heterogeneity of litter composition, habitat area, age of restoration), to enable robust examination of the effects of selected factors. To monitor assemblage composition, arthropods were collected using two methods: pitfall traps and extraction from litter. Responses of arthropods were analysed at two main levels of taxonomic resolution: ‘coarse’ arthropods (all arthropods sorted to Order/Class) and ants, identified to species. Before the field experiments, a survey was carried out to collect reference information on the distribution of soil and litter arthropods in remnant rainforests (undisturbed reference sites) and cleared pasture (disturbed reference sites) in the study region. Regardless of the sampling method (pitfall or litter extraction) or taxonomic resolution employed (coarse arthropods or ant species), the composition of arthropod assemblages clearly differed between rainforest and pasture. The information obtained from this survey generated potential bio-indicators of forested and cleared habitats, assisting interpretation of the data obtained from the field experiments. The effects of habitat isolation and inoculation were tested using ‘restored’ habitat patches which were established within cleared pasture at increasing distances (0, 15, 100 and ca. 400 m) from the edges of rainforest remnants. After nine months, rainforest-dependent taxa were found to have only colonised the habitat patches closely adjacent to rainforest remnants. Attempts to increase the extent of arthropod establishment by inoculation were unsuccessful: the majority of rainforest arthropods from the raw inoculum failed to persist within the isolated plots. The results indicated that many forest-dependent soil and litter arthropods may have a limited capacity to colonise isolated restoration sites, and/ or small experimental plots in the short term. Inference from the experiment was potentially limited by the relatively small temporal and spatial scales of restoration treatments. Avoiding these limitations in future research may require controlled and replicated efforts in experimental restoration over larger areas, based on collaborations between researchers and practitioners. To test the effects of quality and quantity of substrate on arthropod colonisation, habitat patches were established by adding either sterilised hay (a conventionally used mulching material in restoration projects) or woodchip mulch (a structurally more complex alternative), each at two depths (3-5 cm, 10-15 cm). Habitat patches were positioned within pasture adjacent to the edges of rainforest remnants to minimise the effect of isolation, and were all unshaded to create conditions similar to those during the initial stages of rainforest restoration. Despite its simple composition, hay performed better than woodchips in facilitating colonisation by arthropods characteristic of rainforest. However, neither hay nor woodchip mulch inhibited arthropods invading from the surrounding pasture. Shallow hay was favoured by ants characteristic of rainforest, but other groups of arthropods (e.g. Coleoptera, Isopoda) were associated with deep hay (10-15 cm). The optimum amount of hay may therefore vary among different groups of arthropods. The effects of shading and mulch depth, and potential interactions between them, were tested using habitat patches created with varying degrees of shading (none, 50% or 90% shading) and two depths of woodchip mulch (3-5 cm or 10-15 cm deep). The presence of shading, at both 50% and 90%, encouraged colonisation of habitat patches by arthropods characteristic of rainforest. However, only the more complete shading treatment (90%) inhibited re-invasion of restored patches by arthropods from the surrounding pasture habitat. Effects of mulch depth were significant only for rainforest-associated ant species which responded positively to shallow mulch within shaded plots. These results suggest that moderate levels of canopy closure, as produced by tree spacings typical of timber plantations, may be sufficient to facilitate colonisation of reforested land by rainforest arthropods. However, greater canopy shading (90%) is likely to be needed to inhibit re-invasion of arthropods from surrounding pasture habitat. Using deeper woodchip mulch does not necessarily create more suitable conditions for rainforest arthropods or offset the deleterious effects of the lower levels of shading. Paired herbicide-treated and control plots were created within rainforest remnants to test the short- (approximately three days) and long-term (approximately three months) impacts of herbicide application on soil and litter arthropod assemblages on the floor of the remnant rainforests. The results found no deleterious effects of glyphosate herbicide formulated as Roundup® Biactive™ on rainforest soil and litter arthropods; hence, this herbicide appears suitable for the control of unwanted plants in rainforest restoration projects, from the perspective of arthropod biodiversity. The outcomes of this study also have a number of important implications for the monitoring of the development of soil and litter arthropod assemblages in restored rainforests. First, pitfall traps (a commonly used sampling technique) can provide sufficient information on the state of arthropod assemblages in the context of subtropical rainforest restoration projects, although samples collected by this method alone do not necessarily represent the whole suite of soil and litter arthropods (e.g. cryptic arthropods that live in soil and litter). Second, a combination of higher-taxon sorting of all arthropods, together with species-level sorting of a significant major taxon (ants), provides a feasible compromise between comprehensiveness and detail in monitoring responses of arthropods. Third, ‘composite habitat indices’, such as those developed in this study to quantify the extent to which a site resembles rainforest or pasture in terms of its arthropod assemblage, can help alleviate problems associated with the patchy distribution of arthropod taxa in monitoring samples. The experimental approach adopted in this study provided information that would otherwise have been limited by post-hoc empirical studies alone. This study’s results demonstrated that the selected aspects of different restoration techniques and management affect the colonisation of soil and litter arthropod assemblages in rainforest restoration of old fields.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Faculty of Science, Environment, Engineering and Technology
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42

Vanderklift, Matthew A. "Influence of adjacent seagrass on the fish assemblages off sandy beaches." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1996. https://ro.ecu.edu.au/theses/946.

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As we attempt to maintain marine biodiversity mainly by focussing on habitats, we need to understand how marine biodiversity is affected by seagrass loss. Although managers and researchers widely acknowledge that habitat loss results in changes to marine biodiversity, quantitative knowledge of these changes is generally poor. In this study, fish assemblages (as one component of the biodiversity of sandy beaches) were examined in Cockburn Sound, Western Australia, to assess patterns that may be related to presence or absence of adjacent seagrass beds, If consistent patterns are evident, they may enable predictions regarding the effects of seagrass loss on the fish assemblages. Prior to examination of this main question, seagrass and bare sand habitats were sampled as part of a pilot study. Analyses of the data collected concentrated on examining the biases and variability associated with different sampling gear, and changes in the precision of estimates derived from different levels of replication. Further consideration was given to reducing the relative weighting of very numerous species in analyses by examining the effects of data transformation. Results suggest that researchers seeking to detect a 'signal' of environmental change amid the 'noise' that results from variability in catches and the numerical dominance of a few species should select methods of sampling, levels of replication and types of data transformation with an understanding of the associated influences. The main sampling program was conducted in May-June and October November 1995 (months identified as suitable pre- and post-recruitment periods), over six beaches in Cockburn Sound. Assemblage and population level analyses indicated that consistent trends related to the presence of adjacent seagrass were not evident, as differences among beaches was the dominant spatial trend. Several environmental variables appeared to influence these differences. The most significant were water depth, wind, amount of drift seagrass and wave exposure. Degree of exposure and amount of drift seagrass probably had the greatest structuring effects on the species assemblages. Both were determined by the position of habitat patches in relation to wind direction and proximity of other habitats, Although patterns associated with the presence or absence of adjacent seagrass Were not clear, these findings indicated that seagrass beds had considerable influence on the fish assemblages of some beaches, Populations of some species changed between May-June and October November due to recruitment of juveniles to the beaches. Although juveniles of some species use other habitats, there is a strong suggestion that the beaches of Cockburn Sound are regionally important in the ecology of species such as Aldrichetta forsteri, Ammotretis elongatus, Sillago uittata and Sill ago schomburgkii. Seagrass loss in Cockburn Sound is unlikely to have affected the more mobile fish species, but is likely to have caused a decline in the populations of less mobile, site-associated species of both seagrass and sand habitats. Additional loss of seagrass within Cockburn Sound is likely to further reduce the populations of many species. If these components of biodiversity are to be maintained, then management of marine biodiversity in the region needs to be conducted with a recognition of the differences in assemblage composition among habitat patches. Conservation of just a few habitat patches will not adequately represent the full range of species and age classes present.

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Taukulis, Fiona E. "Diatom communities in lakes and streams of varying salinity from south-west Western Australia : distribution and predictability." Curtin University of Technology, Dept. of Environmental Biology, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=17715.

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The distribution pattern of diatoms from lakes and streams of varying salinity in the south-west of Western Australia was investigated. A total of 95 water bodies were sampled and separated into freshwater (<3 ppt), hyposaline (3-20 ppt), mesosaline (20-50 ppt) and hypersaline (>50 ppt). The south-west and specifically the inland wheatbelt region has been severely influenced by secondary salinisation, due to clearing of native vegetation for agriculture. There has been little research on diatom communities from salt-affected systems, with this data providing the basis for the development of an inference model based on species optima and tolerance limits to salinity. Physico-chemical variables measured from the study sites were collated and assessed. Salinity ranged from freshwater (0.04) to hypersaline (156.80 ppt), and pH ranged from acidic (2.90) to alkaline (10.51). Dissolved oxygen levels were recorded from 1.11 to 18.67 mgL-1, water temperature from 6.30 to 28.10 °C and peripheral vegetation scores from 1 (little or no cover) to 5 (dense cover). Analysis of variance (ANOVA) showed that salinities were significantly higher in standing waters located further inland, compared to flowing waters in high rainfall areas. Hypersaline wetlands displayed significantly lower dissolved oxygen levels, higher water temperatures and reduced peripheral vegetation, compared to freshwaters. The pH of hypersaline sites was also significantly lower, associated with surrounding land use or underlying geology. The data collected provides important baseline information, with implications for aquatic biota.
The community structure of diatoms in relation to varying salinity concentration was explored. An artificial substrate collector (JJ periphytometer) was used to standardise sampling and ensure diatom assemblages were representative of ambient water quality. A total of 217 taxa were identified with the highest diversity observed in freshwater sites (up to 33 species), and limited to less than 15 in hypersaline waters. According to BIOENV, salinity was the key factor influencing diatom community structure. SIMPER analysis found a number of discriminating taxa between salinity ranges, specifically between assemblages from freshwater and hypersaline sites. Taxa such as Achnanthidium minutissimum and Gomphonema parvulum were indicative of freshwaters. In comparison, Amphora coffeaeformis and Nitzschia ovalis were associated with hypersaline water bodies. Diatom community structure was also examined from 20 hypersaline wetlands in the wheatbelt region with varying pH. Characteristic taxa including Amphora coffeaeformis, Hantzschia sp. aff. baltica and Nitzschia ovalis showed a wide tolerance to salinity and pH, or hypersaline acidic conditions. BIOENV analysis found there were no observable differences between diatom assemblages in relation to salinities above 50 ppt and that pH was highly correlated to species composition. The increasing occurrence of acid saline lakes is of concern and is most likely attributable to deep drainage practices and continued use of fertilisers in agricultural areas.
A diatom-based transfer function was developed from the south-west dataset, to document species optima and tolerance limits to salinity. CCA analysis showed that salinity accounted for a significant and independent amount of variation in the diatom data enabling an inference model to be derived. The most successful model was generated using tolerance-downweighted weighted averaging, with a high coefficient of determination and low prediction errors that remained high after jackknifing. The optima of freshwater diatoms were similar to those reported from other regions of the world, although the optima of hypersaline species tended to be higher. Comparatively, the model performed very well, with the potential to be applied in future paleolimnological studies. In conclusion, this study has shown diatoms to be effective biomonitoring tools, providing the basis for future sampling strategies that assess the biodiversity of salt-affected water bodies in Western Australia. Potential indicator species from different salinity ranges were identified and the sensitivity of diatoms allowed for the development of a statistically robust inference model for the south-west. The reported optima and tolerance limits of important taxa may be further explored to evaluate the success of remediation measures implemented for secondary salinised systems in this region.

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Delnevo, Nicola. "Conospermum undulatum: insights into population genetics and pollination ecology of a threatened species." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2020. https://ro.ecu.edu.au/theses/2398.

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Fragmentation of natural vegetation is currently one of the largest threats to biodiversity. Within the southwest Australia global biodiversity hotspot, the Swan Coastal Plain was historically cleared for agriculture and forestry and is now experiencing extensive land clearing for urbanisation. The wavy-leaved smokebush Conospermum undulatum is a rare species endemic to the Swan Coastal Plain, and its future persistence is threatened by urban expansion. Throughout this research, I investigated the pollination ecology of this species and found a specific association between C. undulatum and native bees for pollination. I also demonstrated that C. undulatum has evolved pollen with resistance to the usually negative effect of ant secretions on pollen grains, with ants providing effective pollination services to this threatened species. Native pollinators were drastically reduced in small populations, and urbanisation limited the movement of pollen across built-up areas surrounding remnant bushland. This lack of both pollinators and inter-population pollen flow is severely limiting the production of healthy seeds in smaller populations. I then performed molecular investigations combined with an ecological characterisation of the recently fragmented distribution range of C. undulatum to quantify the genetic structure and levels of genetic diversity across the entire distribution of the species. Despite the current intense fragmentation, I found levels of genetic diversity similar across populations and a weak spatial genetic structure. Since habitat fragmentation is recent and many adult plants are likely to be several decades old, they mainly reflect pre-fragmentation conditions. Therefore, the detailed characterization of fragmentation over time has shown how the low levels of genetic fixation can be attributed to pervasive gene flow through the pre-fragmented landscape, which mostly influenced the current adult cohort. Early signals of the negative effects of habitat fragmentation were found during my study of contemporary gene flow through the paternity assignment of seedlings sampled at the end of the 2017 flowering season. Although gametes of C. undulatum could flow unimpeded through large expanses of unfragmented bushland, inter-population pollen flow was non-existent between fragments surrounded by built-up areas. This study supports the need for an understanding of contemporary mating patterns to detect early signals of gene flow failure in fragmented remnants. Lastly, I found evidence for hybridisation occurring at the edge of the distribution of C. undulatum between this rare and threatened plant and two other related species. This adds to the threats posed by habitat fragmentation to the conservation of C. undulatum. My research highlighted the importance of native pollinators for plants that coevolved with them and adds to the limited research on the effect of habitat fragmentation on native plants that rely exclusively on native insects for pollination. Such pollinators appeared unable to maintain an adequate inter- population pollen flow in heavily fragmented landscapes. Therefore, the often negative effects of habitat fragmentation can be exacerbated in small and isolated populations of plants that rely on species-specific pollinators for sexual reproduction. Outcomes of my research will inform recovery plans to enhance the future persistence of C. undulatum over the long term.

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Guthrie, Ruth J. "Patterns of invertebrate distribution and abundance on Cordyline australis in human-modified landscapes." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/1235.

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Fragmentation of forest habitat by urban and rural development has had profound effects on the distribution and abundance of many native species; however, little is known about the ecological processes driving patterns in community structure (species richness and composition) of host-specialised herbivores in modified habitats. I examined patterns in community structure of 9 specialist and 19 generalist invertebrate herbivores of cabbage trees (Cordyline australis Laxmanniaceae) across a highly-modified landscape. I found that, although species richness of specialists was highest in forest sites, the majority of host-specialised species were not restricted to forest habitats and were as widespread as many generalists. In terms of site occupancy, only two specialist and four generalist species were rare. I show that patterns of species occupancy and abundance reflect differing susceptibility to habitat modification, with landscape-level variation an important predictor of abundance for nearly all species. When species occurrences and life history traits were considered I did not find strong evidence for the importance of dispersal ability, which suggests that habitat variability had a stronger organising effect on the community. In a replicated common garden experiment, I found distinct regional patterns in the community structure of the specialist invertebrates occurring on different phylogenetic groups of C. australis. In contrast, community structure of generalist herbivores did not differ significantly among host genotypes. I speculate these patterns are due to historical changes in the distribution of cabbage trees in the Southern phylogenetic region that caused specialised herbivores to become locally adapted on populations of low genetic diversity following expansion after the last glacial maximum. However, this consistent selection pressure did not occur in the Northern region where C. australis habitat has been more consistently available over the past tens of thousands of years, reflected in higher host genetic diversity. This study has advanced our understanding of the patterns in community structure of an indigenous, host-specialised fauna in a highly modified and fragmented urban and rural landscapes.

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Pentland, Craig. "Behavioural ecology of the black-flanked rock-wallaby (Petrogale lateralis lateralis): Refuge importance in a variable environment." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1280.

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The black-flanked rock-wallaby (Petrogale lateralis lateralis) has suffered a significant decline in its distribution in Western Australia. This has been attributed to introduced predators (predominantly the red fox) and herbivores, fire, and habitat destruction due to clearing. Although since 2001 the Department of Environment and Conservation (DEC) had begun to reintroduce this species back into its former range, little was known of the behavioural ecology of this species. Fox control in the 1980s and 1990s resulted in population increases of rock-wallabies on several reserves in the central wheatbelt of WA. However, recently these populations have rapidly declined despite continuing fox control. All too often, management and conservation programs are based on little understanding on the natural history and ecology of animals, which can ultimately result in poor management. One of the major problems with our understanding of the ecology of P. l. lateralis was that there was little information on their behavioural, foraging and feeding patterns, and how these affect the population dynamics of the species. Although this species appears to be substrate bound, requiring complex rock structures that are believed to protect them from both predators and adverse climatic conditions, there was still little understanding of how these animals utilise this important resource, particularly in highly variable environments. There is a long-standing premise in behavioural ecology that highly variable environments can significantly affect the behaviour and demography of animal populations. Although this has been well documented in birds, and primates, behavioural elements are rarely incorporated into marsupial studies. For the success of any current and future reintroductions of rock- wallaby populations into new areas, we needed to understand the relationships between the landscape and climatic elements and the behavioural patterns and population dynamics of the species’. This study describes the behavioural ecology of the rock-wallaby subspecies P. l. lateralis in the central wheatbelt region of Western Australia. It focuses on environmental variables that have rarely been studied simultaneously, those of climate, fear of predation and conspecifics, and habitat structure. The Nangeen Hill Reserve population was chosen because it is one of seven small fragmented reserves, within a landscape, with strong seasonal climatic patterns. A methodological approach was developed that enabled identification of the key ecological determinants of the foraging and feeding behaviours of P. l. lateralis in this highly variable environment. The study included a comprehensive examination of all the behavioural characteristics and abilities of P. l. lateralis, compiling a detailed behavioural repertoire (ethogram), a first for this species, and included both nocturnal and diurnal observations. P. l. lateralis uses a complex arrangement of non-agonistic and agonistic behavioural acts that determines its social organisation, and indicates a linear dominance hierarchy. There is little vocal communication, and instead the rock-wallabies appear to rely on both ritualised behaviour acts and chemical cues to exchange information about the physiological or behavioural state of the individual, thus evolving very diverse and complex social behaviours. Nangeen Hill rock-wallabies occupy a permanent central rock refuge, with strong signs of site fidelity. Their foraging patterns reflect those of a central place forager, but distances travelled are restricted in open habitats, with stronger preferences for areas of rock structural complexity. Their foraging behaviour is not strictly nocturnal nor can it be considered crepuscular, exhibiting significantly different seasonal patterns. Time allocation for foraging is strongly affected by fear of predators and to a lesser extent conspecifics, and certain climatic conditions. Although rock-wallabies use multiple behavioural strategies to reduce predation risk, energy costs, and intraspecific agonistic interactions, they can only can survive in their present environment if they have access to complex rock refuge. This rock resource not only enables them to avoid extreme ambient temperatures, but also gives them protection against predators particularly when environmental conditions are unfavourable. In addition, their cave refuge also gives them protection from precipitation, reducing heat loss, and provides a safe environment for both rearing young and for courtship without the cost of predation. Rock refuge is the most important resource that defines this species and is central to all aspects of its life history. Although this reserve has been under a fox-baiting program since 1982, and subsequently resulted in a rock-wallaby population increase and habitat expansion, within the rocky outcrop (Kinnear et al., 1998), it was clear from my research that the ecological situation was more complex. There is a strong predation influence on the behaviour indicating that the population is now predominantly fear-driven. It is the fear of predators and dominant conspecifics that restricts both the foraging range and time spent feeding. This results in animals being tightly restricted to their rock refuge, resulting in overgrazing and habitat degradation. These concerns led me to believe that if the current situation was not alleviated, then a population crash was imminent.A population crash subsequently happened in 2010, and the cause of this decline is a result of a complex ecological relationship, that includes direct and indirect predatory effects, weed invasion, and drought. The results of this research and the subsequent recent population decline, show the importance of including behaviour into an ecological study to have a better understanding. It provides a better understanding of a species as well as providing important insights into its evolutionary past, and how this has shaped their social and demographic patterns. This research also demonstrates how the use of a permanent central rock refuge both contributes to the animal’s continued survival, and restricts its future distribution, particularly in ecologically altered landscapes. Although this study was not designed primarily to resolve conservation and management problems, its findings are already being used to design an active management plan for the central wheatbelt rock-wallaby populations. The complex relationships between how an animal obtains and uses its resources, the availability of different vegetation patches, and population demographics creates significant problems for the management of a species. This emphasises the need for future research on all animal groups, to understand the relationships between the habitat and landscape elements, and that of behaviour and population dynamics. Understanding how animals perceive their environment and how they adjust to its changes will be paramount for the future management and survival of many species.

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Alexander, Jane. "Ecology of long-tailed bats Chalinolobus tuberculatus (Forster, 1844) in the Waitakere Ranges: implications for monitoring." Lincoln University, 2001. http://hdl.handle.net/10182/1682.

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The long-tailed bat (Chalinolobus tuberculatus) is a threatened species endemic to New Zealand. Historical anecdotes indicate that long-tailed bat populations have declined. However, it is unknown if all populations have declined and if declines are historical or ongoing. Thus, the development and implementation of a national network of long-tailed bat monitoring sites is a priority of the Department of Conservation's Bat Recovery Plan. Potentially, information gained from a national monitoring programme would assist conservation managers to target resources towards those areas where bat populations are declining and provide baseline information to assist managers to gauge the impact of management techniques on bat populations. Of critical importance is that unless it can be demonstrated that long-tailed bat populations have declined and that, that decline is real, management will not be initiated. The aim of this research was to investigate aspects of the ecology of long-tailed bats that would influence the development of a monitoring programme. The distribution, roost selection, habitat use, and activity patterns of a long-tailed bat population that persisted in the Waitakere Ranges, Auckland, were investigated. A study of the Waitakere Ranges long-tailed bat population was significant because (1) the Waitakere Ranges is the northern most location at which long-tailed bats have been researched; (2) the study was the first to be conducted on a long-tailed bat population that persisted in kauri Agathis australis dominated forest remnants; (3) the long-tailed bat population in the Waitakere Ranges is the only known extant population in close proximity to a major urban area; and (4) the factors that are attributed to long-tailed bat population declines (i.e., forest clearance, predation and urbanisation; O'Donnell, 2000) are likely to be ongoing and intensified in the Waitakere Ranges. Twenty roosts were located. Most roosts (85%) were in kauri, 2 were in mature rimu (Dacrydium cupressinum) and 1 was in a kahikatea (Dacrycarpus dacrydioides). All roosts were in large, live, emergent trees. Mean height of roost trees was 38.4 ± 1.3 m and average DBH was 186 ± 12 cm. The entrances of six roost cavities were identified all were located in minor lateral branches in the crown of the tree and were primarily near the tip of branches. Roosts were a mean height of 24.6 ± 3.7 m above ground level. It was argued that roosts in the crowns of kauri were inaccessible to terrestrial mammalian predators. Twenty-eight roost watches were conducted. The average number of bats counted leaving roosts was 10.0 ± 1.5 (maximum = 24). Roosts were occupied by radio-tagged bats for an average of 2.0 ± 0.4 days, and 11 (55 %) were occupied for only one day. Roost size was the lowest reported for long-tailed bats. Roost switching also appeared higher than in other populations that have been studied. It was argued that morepork predation may have a significant impact on the population viability of the population. As in other studies long-tailed bats were found to forage over modified habitats including over farmland, dwellings, orchards and along streams and roads with little vehicular traffic. Long-tailed bats foraged throughout the Waitakere Ranges and their foothills. Bat activity was highly variable. Of the environmental variables analysed, temperature was found to have the greatest influence on bat activity. There were seasonal and habitat influences on bat activity. The relationship between sample sizes, variation in bat detection rates and desired statistical power using automatic bat detectors to monitor populations of bats was explored. A power analysis on activity data collected with automatic bat detectors indicated that declines in bat populations would need to be reflected in declines of greater than fifty percent in bat activity before monitoring programmes would have sufficient power to detect declines in activity. It was recommended that monitoring programmes should concentrate on intensive presence – absence surveys rather than long-term studies at a few sites.

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Burnett, Peter Keith. "Australia's National Approach to 'Ecologically Sustainable Development': Success in Principle, Failure in Policy, Still in Prospect." Phd thesis, 2018. http://hdl.handle.net/1885/156800.

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Why did Australia’s national policies on Ecologically Sustainable Development (ESD) fail? Almost thirty years after Australia first adopted ESD as the overarching goal of national environmental policy, and with little discernible evidence of policy impact on general environmental decline over this time, the thesis seeks to answer this question by examining the need for a concept such as ESD; the coherence of the concept itself as a social goal; and, through four case studies, the coherence of policies directed to advancing ESD. The case studies consider national policy on environmental information; the National Strategy on ESD (1992); National Biodiversity Strategies from 1996 to date; and environmental impact assessment under the Environment Protection and Biodiversity Conservation Act 1999 (Cth). The research is based on the historical analysis of official records, with particular reference to policy advice to governments and subsequent policy statements. In this regard, the researcher had access to the records of the Department of Environment as well as to publicly available records. The thesis argues that ESD is a necessary concept in responding to the problem of General Environmental Degradation and Depletion (GEDD), because although mainstream policy approaches, especially those based on welfare economics, are capable of making major inroads to the problem, ultimately they are not well-adapted to addressing the intergenerational nature of environmental decline. Moreover, ESD is a viable concept because it is a clear, relevant and coherent response to the broader social goal of halting and reversing GEDD, and feasible of achievement. By reference to the four case studies, the thesis goes on to argue that the policy means chosen to achieve ESD were unsuccessful because they were not well-adapted to achieving it. Beyond the more obvious direct causes of policy failure such as weak institutionalisation and under-investment, the thesis identifies possible ultimate causes of failure. While these causes include the possibility of deliberate political choices to pursue ‘facade’ policies that create only the appearance of pursuing ESD, the more significant reasons are more complex and stem from an initial decision to pursue this ‘grand policy’ goal without a commensurate ‘grand policy process’. Although a grand policy process was adopted subsequently, critical decisions had already been made and the process was cut short abruptly as a result of political factors. The consequences of these failures of process include underestimation of the gravity of the problem, the implications of pursuing ESD, and the vital role of the States in environmental management under Australia’s federal system. The thesis concludes that, properly understood and incorporated into an appropriate policy framework, ESD is a coherent and viable concept, one which remains in prospect when and if society returns the problem of general environmental decline to the top of the public policy agenda.

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Lentini, Pia Eloise. "The conservation value of Australia's stock route network : a multi-taxonomic approach to management and planning." Phd thesis, 2012. http://hdl.handle.net/1885/149871.

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Stock routes have been a feature of the Australian landscape since the mid-1800s. Originally established to provide corridors of forage and shelter for livestock droved 'on the hoof', the vegetation within them remained standing while vast tracts in the surrounding landscape were cleared to make way for agriculture. However, livestock are now more commonly transported in trucks, so managing authorities no longer receive adequate income from droving permits to offset costs. At the commencement of this PhD it was being suggested that some stock routes would be lost to freehold tenure, in spite of the fact that many scientists believed them to be of great value for conservation. This project was structured into three distinct sections, aimed at providing evidence for the values of stock routes, and advice on how to best manage and plan for them into the future. The first section took the form of a literature review and spatial analysis, where I demonstrated that stock routes plays a considerable role in biodiversity conservation, recreation, tourism, preserving Indigenous cultural heritage, and as a stock refuge. I also found that they occupy fertile, low-lying areas of the landscape, and contain associated vegetation communities which have been preferentially cleared for agriculture and are under-represented in protected areas. In the second empirical section of the project I conducted surveys of three taxonomic groups which provide ecosystem services: woodland birds, wild bees, and insectivorous microbats. Data were collected from 32 stock routes which varied in width and vegetation condition, and in the fields adjacent to these stock routes. Statistical modelling was then used to quantify the response of each group to local and landscape variables characterising the survey sites. Although specific responses were different for each taxonomic group, there were some consistencies in my findings. Scattered trees in fields had a positive effect on all taxa, and the value of both native pastures and formal conservation areas close to the stock routes was also a recurring pattern. In the final section of my thesis I concentrated on the debate surrounding connectivity; whether it should be included as a goal in conservation planning, and whether this will result in trade-offs with habitat area and quality, or economic costs. It would seem logical to plan for connectivity if some stock routes are to be sold whilst others are retained for conservation purposes. Using them as a case study, I ran a Marxan minimum-set analysis which demonstrated that only certain connectivity approaches had effects on the costs and siting of reserves in conservation planning, and these effects were substantial only when conservation targets were set high. At the time of writing, the future of the stock route network remains as uncertain as it was in 2009. However, through this work I have been able to provide a much more solid foundation for potential conservation decisions than was previously available. I have also demonstrated that the stock route network is an indispensible environmental heritage asset, which should be retained and managed for conservation in perpetuity.-- provided by Candidate.

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Perry, Justin James. "Fire management and biodiversity in Northern Australia." Thesis, 2016. https://researchonline.jcu.edu.au/48796/1/48796-perry-2016-thesis.pdf.

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Fire is a significant ecological determinant of patterns of plant and animal distributions across the globe. This is especially so for the tropical savanna biome as fire is intrinsically linked with a dynamic weather-driven interplay between C4 grasses and other vegetation types. We know that climate change will dramatically alter global ecosystems in the future, but the implications for savanna ecosystems are less clear. The potential changes are often discussed in terms of how things may alter up to 100 years into the future. In most cases these forecasts are too abstract to translate for land managers who need practical advice that will allow them to adapt in real time and that acknowledges the considerable challenges they face now. For this thesis I have sampled fire and vertebrate fauna in the dominant vegetation type in northern Australia, open savanna woodland, and used these data to test several hypotheses that will help decision makers and land managers better understand fire management both now and into the future. To adapt to future change and to make better decisions about the current conditions we need to understand the determinants of fire, how these are linked to climate, the impact of human intervention through various fire management strategies, and what the likely implications for biodiversity are. In this thesis I examine fire and biodiversity at a variety of scales, ranging from pyro-diversity models derived for all of northern Australia to a set of representative sites surveyed on Cape York Peninsula for the three dominant vertebrate taxa (birds, mammals and reptiles). The thesis includes six chapters that begin at the broadest scale (all of northern Australia) and then drill down in scale for the various vertebrate fauna responses. Chapter 1 introduces fire as a disturbance regime and a ubiquitous part of northern Australia land management. It outlines the structure of the thesis and describes the connectivity of chapters. Chapter 2 sets the scene for the distribution of fire in northern Australia from a climatic perspective and explicitly links weather and vegetation to fire distribution in recent history. This places the contemporary distribution of fire in a broader temporal perspective and outlines the implications of fire on carbon emissions and describes the variance in annual and inter-annual fire distributions. Chapter 3 compares contemporary fire management strategies with traditional Aboriginal burning and discusses the challenges of supporting traditional burning with modern requirements such as infrastructure protection and financial incentives for reducing greenhouse gas emissions. In chapter 4 I explore the links between burning for greenhouse gas abatement and vertebrate fauna in savanna ecosystems of Cape York Peninsula. Carbon farming initiatives have rapidly developed in recent years creating incentives for broad scale changes to land management regimes. In the open carbon market a premium can be secured if additional benefits, such as biodiversity conservation or social advancement, can be quantified. In Australia, there is an accepted method for carbon abatement that requires shifting fire frequency from predominantly late to early dry season fires. There is an assumption and some evidence that this might accrue co-benefits for biodiversity. We tested this assumption by comparing terrestrial vertebrate biodiversity patterns (richness and abundance of reptiles, birds and mammals) against increasing fire frequency in the early dry season at the same spatial resolution as the savanna burning methodology. Chapter 5 examines the contemporary distribution of mammals on Cape York Peninsula (data collected for this thesis) in comparison with limited historical data and changes in mammal fauna across northern Australia. I contextualise the changes in mammal populations with the historical disturbances present in the study area which includes changes to fire regimes. Chapter 6 focusses on reptiles, one of the most abundant and diverse taxa in savanna ecosystems. Theoretically, if fire changes vegetation patterns then reptiles, as a heliothermic organism should be a good indicator of the impact of altered fire regimes. Chapter 7 looks at changes in bird distributions across time in the study area. A systematic survey of the avifauna of Cape York Peninsula was conducted in the late 1990s and early 2000s providing an ideal basal dataset for measuring change in the avifauna. A subset (n > 600) of these sites, primarily within savanna landscapes, was selected for re-survey in 2008 to investigate changes in bird communities on Cape York Peninsula. Long-term monitoring can describe important patterns of species change over time, though in the case of large, highly seasonal environments like the tropical savannas, signals of change may manifest over decades rather than annually. Chapter 8 discusses the broad implications of this research and describes how each chapter has collectively increased the understanding of the impact of fire on biodiversity in northern Australia. This thesis provides the first major assessment of fire and biodiversity in the savanna ecosystems of Cape York Peninsula and uses novel analytical methods to demonstrate significant shifts in fire frequency in recent history. This dataset and the associated analysis and interpretation has provided a substantial improvement to the collective knowledge of fire and terrestrial vertebrate fauna across northern Australia.

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Dissertations / Theses on the topic 'Australia's biodiversity'

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