Spatially explicit cost-effective actions for biodiversity threat abatement

Abstract

Biodiversity decline is indisputable, and rates of future decline depend on whether threats to species persistence are abated. However, current resources for threatened species management are less than required to stop further decline. Management that abates many threats to many species is necessary, yet decisions about how to do this under resource constraints are inherently complex. My thesis incorporates systematic conservation planning and cost-effectiveness analysis in a decision-support framework for prioritising spatially-explicit management actions for many species across a region.By prioritising action where it is expected to provide the greatest benefit to the most species at least cost, my research advances the thinking on decision support, and contributes to the effort to reduce biodiversity decline.Using information on threats to species that was compiled by the Queensland, Australia government, my research develops a decision-support process for managing threats to threatened species in a bio-diverse regional-scale management area, the Burnett-Mary Natural Resource Management Region. In my thesis, predicted distributions for 65 threatened species are modelled on co-occurring presence-only species locations and ecologically-meaningful environmental data.Three threats are addressed: invasive red fox predation; too frequent and intense fire; and habitat degradation from overgrazing. Indirect threat maps are made by combining predicted distribution models of species vulnerable to specific threats and are used to identify locations where threatabating actions are most likely to provide benefit to species. Management action costs are estimated for fox control, on the basis of a roadside baiting strategy; proactive fire management, on the basis of vegetation type and proximity to human structures; and stewardship agreements to reduce grazing, on the basis of foregone agriculture profit. Spatially combining the costs and benefits of threat-abating actions leads to the ability to prioritise cost-effective locations for actions. Within the context of prioritising regional threat management actions, my research examines four topics.Firstly, an understanding of where species are affected by threats determines where to direct management. Indirect threat maps are made by combining threatened species distribution maps, but are sensitive to map scale in guiding spatially-explicit threat management efforts (Chapter 2).Using fine-scale predicted species distribution models to derive indirect threat maps, instead of general range maps, may lead to better regional management decisions.Funding limitations for threat management require that choices be made when not everything can be done. Transparent and rigorous decision support is provided by prioritising management ranked on the most, to least, cost-effective actions and locations, and is made accessible when calculated with readily-available spreadsheet and mapping software (Chapter 3). Cost-effective management iii priorities are determined by combining ind...

Effects of threat management interactions on conservation priorities

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How to prioritize species recovery after a megafire

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Changing Fire Regimes in Tropical and Subtropical Australia

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