Location biases in ecological research on Australian terrestrial reptiles

Understanding geographical biases in ecological research is important for conservation, planning, prioritisation and management. However, conservation efforts may be limited by data availability and poor understanding of the nature of potential spatial bias. We conduct the first continent-wide analysis of spatial bias associated with Australian terrestrial reptile ecological research. To evaluate potential research deficiencies, we used Maxent modelling to predict the distributions of 646 reptile studies published from 1972 to 2017. Based on existing distributions of 1631 individual reptile study locations, reptile species richness, proximity to universities, human footprint and location of protected areas, we found the strongest predictor of reptile research locations was proximity to universities (40.8%). This was followed by species richness (22.9%) and human footprint (20.1%), while protected areas were the weakest predictor (16.2%). These results highlight that research effort is driven largely by accessibility and we consequently identify potential target areas for future research that can be optimised to ensure adequate representation of reptile communities.Full Tex

Models of wildlife tourism

Catlin et al. (2011) [CJJ] interpreted Duffus and Dearden (1990) [DD, cited in CJJ] to argue (a) that wildlife tourism consists of destinations which grow from smaller numbers of specialist wildlife watchers initially, to larger numbers of generalised mainstream tourists later; and (b) that this produces impacts which exceed limits of acceptable change (LAC) and damage tourist experiences, businesses and wildlife alike. We suggest that this interpretation is incomplete and potentially misleading, for the following reasons.Griffith Sciences, Griffith School of EnvironmentFull Tex

Biotic processes in a coastal dunefield: An assessment of seed removal, with non-native seed removal experiments.

The impact of granivores on coastal dune seed reserves may be high, increasing along a landward gradient from the littoral zone as the structural complexity of the habitat increases. Seasonal removal rates of non-native seeds by nocturnal and diurnal vertebrates and ants from experimental seed trays in two habitats within the Alexandria Coastal Dunefield, South Africa, were determined. Overall, seed removal was higher in the dune-field bush-pocket habitat than the landward thicket habitat. Nocturnal vertebrates were the most important seed removers within bush-pockets. The importance of nocturnal vertebrates decreased in the thicket and there was a shift in the dominant seed removers to diurnal vertebrates. Seed removal by ants and diurnal vertebrates did not differ significantly between the bush-pockets and thicket while that of nocturnal vertebrates showed a significant change. This can be ascribed to the abundance of the omnivorous murid rodentGerbillurus paeba exilis in the bush-pockets which is absent from thicket vegetation.Faculty of Environmental SciencesNo Full Tex

Searching for common ground, a scientific approach to subjective environmental impact assessments: an example from the Kgalagadi Transfrontier Park.

Roads affect ecosystems, biological communities and species in numerous and different ways, determined largely by their location, density, and distribution across the landscape (Hourdequin 2000). Roads generally have negative effects on the biotic integrity in both terrestrial and aquatic ecosystems, and these effects can be classified under seven categories (Trombulak & Frissell 2000): increased mortality from road construction; increased mortality from vehicle collisions; News and Views modification of animal behaviour; alteration of the physical environment; alteration of the chemical environment; spread of exotic species; and increased alteration and use of the habitats by humans.No Full Tex

Propagule bank dynamics in urban subtropical forest remnants: edge effects, fragmentation and plant invasion

Urbanisation places immense pressure on remnant vegetation, driving changes in community structure and impacting ecosystem function. While the influence of urbanisation on extant vegetation communities is relatively well studied, the response of plant propagule banks to such pressures is poorly understood. Propagule banks are important drivers of vegetation dynamics influencing vegetation resilience and adaptive capacity. Here, we investigate the impacts of edge effects and reductions in land area on the composition and structure of three major plant propagule bank sources (aerial, litter and soil) in 20 urban forest patches of varying size in the heavily urbanised region of Greater Brisbane in eastern Australia. We surveyed extant vegetation and conducted glasshouse experiments to examine the composition of propagule banks in edge and core habitats of each forest patch to consider the contribution of these to vegetation dynamics. Germination trials revealed that a high diversity of non-native propagules are stored within propagule banks, particularly at the edges of forests. Edge effects were evident in all extant forests surveyed, manifesting as higher portions of non-native species and changes to species assemblages. Each of the three bank types offered a unique contribution to regeneration potential, and each fostered non-native species. A a distinct disparity was evident between extant and propagule bank assemblages, indicating a risk of extant community shifts in the future. This research highlights the ranging impacts of the urban matrix on propagule bank composition, particularly via the introduction of non-native propagules. Further, the findings presented here highlight the need for management regimes to combat what are clear drivers of biodiversity change.Full Tex

Estimation of the lion (Panthera leo) population in the southwestern Kgalagadi Transfrontier Park using a capture-recapture survey.

Faculty of Environmental SciencesFull Tex

Ecotourism's contributions to conservation: analysing patterns in published studies

Ecotourism is often promoted for its potential to act as a conservation mechanism by: mobilising political, financial and social support for conservation; increasing environmental awareness; protecting sensitive ecosystems and threatened species; and providing an alternate income to land-intensive or consumptive practices. Although instances to date indicate that this can indeed prove highly successful in some circumstances, the conservation impact of the ecotourism sector on a larger scale is unclear. This study identified 70 papers published prior to January 2016 in English language academic journals that examine the conservation actions and outcomes of ecotourism enterprises. There were three key findings within this study. Firstly, conservation actions have been examined more frequently than conservation outcomes. Secondly, there has been a strong focus on indirect approaches to conservation such as visitor education and community-based actions, and a shortage of studies measuring direct impacts on wildlife populations or other components of the natural bio-physical environment. Thirdly, the majority of sites studied are located in developing countries, but the majority of authors are located in developed countries. By identifying these gaps and patterns that currently exist in the academic literature, this review helps to direct and support future research agendas.Griffith Sciences, School of Environment and ScienceNo Full Tex

Biomass estimation within an Australian eucalypt forest: Meso-scale spatial arrangement and the influence of sampling intensity

Plant biomass is important when measuring productivity, calculating carbon stores and when studying interactions between abiotic factors and biotic organisms. However, information on the spatial arrangement of above ground live biomass (AGLB) is lacking and while the influence of replication on estimated AGLB has been studied, it has rarely been the focus in Australian ecosystems. This study examined spatial arrangement of AGLB, the influence of survey design, and interactions between abiotic factors and AGLB. Above ground live biomass was measured in a remnant eucalypt forest at Karawatha Forest Park ( 900 ha), a long term ecological research site (LTER node) within the Terrestrial Ecosystem Research Network (TERN) South-east Queensland Peri-urban Supersite, Australia. Sampling of woody vegetation occurred in 32 one-hectare plots systematically placed at 500 m intervals. Above ground live biomass was estimated to be 146.51 Mg ha 1, with spatial interpolation calculating that there was 133,487 Mg of AGLB (> 1 cm DBH) within Karawatha Forest Park. Time and effort could be saved by not measuring trees 1 cm) would be lost. Despite relatively low variation in AGLB among plots, bootstrapping indicated that at least 15 PPBio (Program for Planned Biodiversity and Ecosystem Research) plots are needed to precisely estimate AGLB within Karawatha Forest Park. Topography and soil chemistry performed poorly at explaining AGLB, and it is likely that past and present human activities (e.g. logging and arson) play a role in influencing AGLB at Karawatha Forest Park. This study identifies the importance of independent replication to capture variation in AGLB for carbon storage estimation, and the power of systematic sampling within sites for mapping carbon stocks at meso and larger scales.No Full Tex

Analyzing and leveraging social media disaster communication of natural hazards : community sentiment and messaging regarding the Australian 2019/20 bushfires

202408 bcchVersion of RecordOthersCommonwealth/State Disaster Recovery Funding Arrangements 2018, AustraliaPublishedC

Review of the Amphibian Immune Response to Chytridiomycosis, and Future Directions

The fungal skin disease, chytridiomycosis (caused by Batrachochytrium dendrobatidis and B. salamandrivorans), has caused amphibian declines and extinctions globally since its emergence. Characterizing the host immune response to chytridiomycosis has been a focus of study with the aim of disease mitigation. However, many aspects of the innate and adaptive arms of this response are still poorly understood, likely due to the wide range of species' responses to infection. In this paper we provide an overview of expected immunological responses (with inference based on amphibian and mammalian immunology), together with a synthesis of current knowledge about these responses for the amphibian-chytridiomycosis system. We structure our review around four key immune stages: (1) the naïve immunocompetent state, (2) immune defenses that are always present (constitutive defenses), (3) mechanisms for recognition of a pathogen threat and innate immune defenses, and (4) adaptive immune responses. We also evaluate the current hot topics of immunosuppression and immunopathology in chytridiomycosis, and discuss their respective roles in pathogenesis. Our synthesis reveals that susceptibility to chytridiomycosis is likely to be multifactorial. Susceptible amphibians appear to have ineffective constitutive and innate defenses, and a late-stage response characterized by immunopathology and Bd-induced suppression of lymphocyte responses. Overall, we identify substantial gaps in current knowledge, particularly concerning the entire innate immune response (mechanisms of initial pathogen detection and possible immunoevasion by Bd, degree of activation and efficacy of the innate immune response, the unexpected absence of innate leukocyte infiltration, and the cause and role of late-stage immunopathology in pathogenesis). There are also gaps concerning most of the adaptive immune system (the relative importance of B and T cell responses for pathogen clearance, the capacity and extent of immunological memory, and specific mechanisms of pathogen-induced immunosuppression). Improving our capacity for amphibian immunological research will require selection of an appropriate Bd-susceptible model species, the development of taxon-specific affinity reagents and cell lines for functional assays, and the application of a suite of conventional and emerging immunological methods. Despite current knowledge gaps, immunological research remains a promising avenue for amphibian conservation management