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    Applying structured decision making for large-scale wildlife management programmes : Project Janszoon as a case study : a thesis presented in partial fulfilment for the degree of Doctor of Philosophy in Conservation Biology at Massey University, Palmerston North, New Zealand
    (Massey University, 2024-11-30) Kenup, Caio
    Managing threatened populations is challenging due to the delicate balance between urgency and uncertainty. While swift action is often needed to prevent further decline or extinction, significant uncertainty frequently surrounds the effectiveness of various management strategies and the future trajectory of populations. This uncertainty complicates the identification of the most effective course of action, especially when resources are limited. Structured decision making (SDM) is an approach that supports informed decision making in the face of uncertainty in conservation projects. The primary aim of this thesis is to develop a decision making framework for Project Janszoon’s bird translocations, guiding management and monitoring decisions to maximise establishment and persistence probabilities for the kākā (Nestor meridionalis) and pāteke (Anas chlorotis). This framework can serve as a blueprint for implementing SDM and adaptive management (AM), promoting their broader use in conservation initiatives within New Zealand and beyond. In Chapter 2, I discuss expert elicitation techniques for generating predictions from expert knowledge while accounting for epistemic uncertainty. Numerical improvements in handling elicited data are proposed, focusing on aggregating and transforming expert-provided values while maintaining their associated uncertainty. Preserving this uncertainty is critical to avoid generating overconfident predictions from expert judgment. In Chapter 3, I explore which uncertainties are worth reducing and to what degree. Value of information (VOI) analysis offers a way to understand how reducing uncertainty affects decision making and conservation outcomes. A key insight from this chapter is that while monitoring is valuable for reducing uncertainty, such reductions do not always improve conservation outcomes. Beyond a certain point, further reductions in uncertainty do not alter decision making. Practitioners must estimate the optimal level of monitoring for each conservation challenge. In Chapter 4, I outline a passive adaptive management framework to reduce uncertainty as management actions are implemented and monitored. The framework’s extendable nature makes it adaptable to other management problems. The tools and concepts presented here are valuable assets for effective decision making for managed populations under uncertainty.
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    Reintroduction of North Island robins to Paengaroa Scenic Reserve : factors limiting survival, nest success, and population viability in a mainland restoration area : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Ecology at Massey University
    (Massey University, 2001) Raeburn, Elizabeth Helen
    Forty North Island robins (Petroica australis longipes) were reintroduced to Paengaroa Scenic Reserve in March 1999. I monitored the survival and breeding success of this population for two years post-release. This study aims to assess survival, nest success, and population viability of robins in Paengaroa in an attempt to discover whether habitat in the reserve is likely to support a population of robins. Survival from the time of release to the start of the first breeding season was lower at Paengaroa than at two other release sites, Boundary Stream Scenic Reserve and Tiritiri Matangi Island. This may be due to higher predator levels at Paengaroa or dispersal out of the reserve. Methods of estimating nest success were compared, and Stanley's (2000) method was found to have advantages over the traditional and Mayfield methods. Daily survival rates of nests at Paengaroa depended on both the stage in the nesting cycle and stage of the breeding season, with the survival rate lowest for early nests at the incubation stage. Nest success for the first two breeding seasons after translocation was compared to that for the first two seasons after release at Tiritiri Matangi and Boundary Stream. Paengaroa had a similar nest success rate to Tiritiri Matangi (25% and 26% respectively), and both of these sites had lower nest success than Boundary Stream (47%). Survival at Paengaroa was most affected by whether a bird was recently-translocated. a juvenile, or an adult. Recently-translocated birds and juveniles suffered similarly low survival rates, suggesting that this high mortality may be due to problems faced when finding and establishing a territory. The survival of juveniles from January to September was estimated to be 29%. The annual adult survival rate was also low (59%). Fecundity and survival estimates were used in a stochastic simulation model to predict the viability of the Paengaroa population. Under current conditions, the population was predicted to have a 17% probability of surviving 10 years. However, variation of parameters to lower and upper 95% confidence limits gave survival probabilities of 0% to 100% over 10 years. When data from the first year after translocation were excluded, the population was predicted to have a 100% probability of surviving 100 years. These results demonstrate the large uncertainly associated with small sample sizes and short-term studies. To assess whether habitat quality is likely to account for the poor overall viability predicted at Paengaroa, the habitat quality at Paengaroa was compared to that at Waimarino forest, where robins still persist. Food supply and predator levels were used to assess habitat quality, as these are obvious factors that may limit viability. Data on food and predator levels provided no indication of why robins may be non-viable at Paengaroa. The power of statistical tests was low due to small sample size, but results suggest Paengaroa has more food as well as fewer rats and stoats than Waimarino. There is a need for further research to improve our understanding of why robins are present and common in some mainland areas but have disappeared from others without any obvious difference in habitat quality. Continued research is also required to reduce the uncertainty regarding population viability at Paengaroa and to determine whether improved management is needed.
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    The impacts of translocation on the cultural evolution of song in the North Island saddleback or tieke (Philesturnus rufusater) : a thesis presented in partial fulfilment of the requirements for the degree of Docotor of Philosophy in Ecology at Massey University, Auckland, New Zealand
    (Massey University, 2011) Parker, Kevin Alan
    The IUCN (1987) defines a translocation as a release of animals with the intention of establishing, re-establishing, or augmenting an existing population. The origins of translocation practise are very much in applied conservation management. However, translocations also provide other outputs. They provide a means by which the general public might connect and commit to conservation and they provide unique opportunities for scientific research because the age and source of founder populations are completely known. Geographical isolation plays a crucial role in speciation events. Thus studies of divergence of behavioural signals in isolated populations have been critical to understanding how barriers to gene flow develop. Bird song is a vital conspecific recognition signal (CRS) and many studies have demonstrated significant geographical variation in song with several hypotheses posed to explain this variation. However, a key problem in testing these hypotheses is an inability to measure the pace of song divergence. This is because the timing and source of founder events are rarely detected. Here I use the NI saddleback or tīeke (Philesturnus rufusater) isolated on a single island in 1964 but subsequently increased by translocation to 13 island populations, to show that significant geographical variation in song can develop in less than 50 years. Furthermore, my data shows a clear signal of serial population bottlenecks (up to 3 times) following translocation and supports both bottleneck and cultural mutation hypotheses in explaining this variation. Critically NI saddleback discriminate between songs from different islands and this discrimination might lead to an eventual reduction in effective population size. This illustrates the potential for human induced founder and isolating events, including conservation management, to be microevolutionary events and challenges us to consider the implications of conservation biology in an evolutionary context.
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    Demography and distribution of the North Island robin (Petroica longipes) in a fragmented agricultural landscape of New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctorate of Philosophy in Ecology at Massey University, Palmerston North, New Zealand
    (Massey University, 2007) Richard, Yvan
    Habitat loss and fragmentation are recognised worldwide as contributing to declines and extinctions of species. However, the biological factors underlying the effects of fragmentation are still often poorly understood, possibly due to the diversity of scales and approaches taken by researchers. I propose in this thesis an integrative approach that can be applied to any taxa and landscape, using a metapopulation of North Island robins (Petroica longipes) inhabiting forest patches of a fragmented agricultural landscape of New Zealand. In particular, I attempt to integrate the effects of habitat fragmentation on both habitat quality and the dispersal-driven broad scale dynamics of populations. I first analysed the distribution of robins based on presence-absence data, relating presence-absence to local habitat factors as well as size and isolation of forest patches (Chapter 2). Their distribution was found to be primarily limited by the isolation of forest patches, but was also related to some habitat factors. However, habitat fragmentation was not found to affect habitat quality, as the factors found to affect survival and productivity were unrelated to size and isolation, independent from the size or isolation of forest patches (Chapter 3). Based on the radio-tracking of juvenile robins, I applied a choice analysis technique to show that robins need woody vegetation for their natal dispersal and that they are unlikely to cross stretches of pasture greater than 150 m (Chapter 4). Juveniles dispersed a median Euclidean distance of 1129 m with a maximum of 11 km, whereas I predicted from the data that they would have dispersed a median distance of 3 km in continuous forest with a maximum of 20 km (Chapter 5). The consequences of this dispersal limitation and of variations in habitat quality were assessed using a spatially-explicit individual-based metapopulation model that incorporated realistic gap-limited dispersal behaviour of juvenile robins (Chapter 6). Whereas the movement of individuals between patches is commonly assumed to improve the persistence of populations, I found that a weaker gap-crossing ability, and therefore reduced landscape connectivity, increased the metapopulation size at equilibrium. This study highlights the complex effects of habitat loss and fragmentation on the distribution of species, but also the limits of excessive model simplification.