Making better decisions for the conservation of threatened species: science, values, and New Zealand's rarest bird

Decision making for threatened species recovery can be complex: there is often a diverse range of stakeholders holding values that may be conflicting, data are typically deficient and imperfect, and there is uncertainty about the outcomes of proposed actions. Yet in this pressured and challenging context, decisions must still be made. Conservationists therefore need the right tools to address these complexities, and structured decision making (SDM) is effective in this space. Here, I demonstrate the utility of SDM and its component tools to assist recovery planning for Aotearoa-New Zealand’s rarest indigenous breeding bird, tara iti (New Zealand fairy tern, Sternula nereis davisae). My PhD aims to advance (i) the way we approach decisions via inclusivity and expression of values, (ii) the way we make decisions by recognising objectives, creating alternatives and making explicit trade-offs, and (iii) the way we use data to support these decisions by analysing and interpreting biased or imperfect datasets. Values drive decisions, and I first demonstrate how SDM, a values-focused approach, can be used to meaningfully integrate stakeholder values such as mātauranga Māori (Māori [indigenous New Zealander] knowledge/perspective) into conservation decisions and provide a basis for co-management between different peoples. Second, I analyse a seabird translocation trial, showing how creative thinking about alternatives can help better achieve conservation objectives. Third, I show how the application of SDM resulted in a new management recommendation that balanced across multiple objectives and was evidence-based. This was the first action after a decade of inaction and communication breakdown between stakeholders. Finally, I use a decision tree and counterfactuals to analyse the efficacy of tara iti egg management, showing how these tools can help navigate complex and biased monitoring data sets to improve future decisions. This thesis provides a detailed real-world example of how SDM can be applied effectively to a complex conservation problem, and highlights the importance of clear, values-focused thinking and inclusive approaches in species recovery