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    Diagnostic investigation into summer mortality events of farmed Chinook salmon (Oncorhynchus tshawytscha) in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Manawatū, New Zealand.
    (Massey University, 2020) Brosnahan, Cara
    Salmon farming is the second highest value aquaculture species in New Zealand and produces approximately 88% of the global market of farmed Chinook salmon, Oncorhynchus tshawytscha (Tucker, 2014). New Zealand salmon are free of many significant diseases affecting salmonids globally (Diggles, 2016). Therefore, disease is one of the greatest threats to this New Zealand aquaculture species. Biosecurity, early detection, and characterisation of new or emerging diseases is vital for management and sustainability of the aquaculture industry. Elevated mortalities termed ‘summer mortalities’ with no cause identified have occurred in certain farmed Chinook salmon populations in the Marlborough Sounds since 2012. This study identified two potential bacterial pathogens involved in summer mortalities; New Zealand rickettsia-like organism (NZ-RLO) and Tenacibaculum maritimum. Distribution of NZ-RLO and T. maritimum within farmed Chinook salmon populations, phylogenetic analysis of these pathogens and the pathogenicity of two strains of NZ-RLO were assessed to provide an understanding of the role of NZ-RLO and T. maritimum in summer mortalities. Additionally, new diagnostic tests were developed to efficiently detect these pathogens. Identification of NZ-RLO in the summer mortalities was the first detection in New Zealand. Tenacibaculum maritimum had been reported in New Zealand previously, however it had not been associated with mortalities. This study confirmed three strains of NZ-RLO with restricted geographical distribution. Two strains of NZ-RLO were found exclusively in areas where fish experienced summer mortalities and were associated with clinical signs of disease, indicating certain strains of NZ-RLO were likely primary pathogens. Widespread distribution of T. maritimum was detected within farmed salmon and no association was found with T. maritimum and clinical signs of disease in areas experiencing summer mortalities, indicating T. maritimum was unlikely to be a primary pathogen. This study proves that laboratory exposure of salmon to two strains of NZ-RLO caused disease and mortalities however, the differences between the two strains suggest NZ-RLO2 may be more pathogenic. This study suggests NZ-RLOs are likely to be involved in summer mortalities as primary pathogens however, the interaction between the pathogens and environment is likely to have amplified the levels of mortalities during these events.
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    What works best when : the role of collaboration in environmental policy and planning : a thesis presented in partial fulfilment of the requirements for the degree of Master of Resource and Environmental Planning at Massey University, Palmerston North, New Zealand
    (Massey University, 2014) Berkett, Natasha Maree
    Conflicting views about the use of natural resources create challenges for environmental management. Scholarly theory suggests that there are different types of policy problem, and these can be identified within a framework that considers the degree of certainty over relevant knowledge, and the degree of consensus on norms and values. By determining and understanding the nature of a policy problem, planning practitioners can choose a problem-solving strategy that is appropriate for different policy problem types. In New Zealand, one policy strategy, collaboration, is increasingly being promoted to resolve conflicts, as collaboration is seen as having more effective outcomes than existing adversarial planning processes. The aim of this research is to explore how collaboration can offer better outcomes for stakeholders involved in environmental resource conflicts, compared to conventional planning processes. This study used Q methodology to examine and explore the scope for collaboration to address a policy problem that arose in New Zealand in 2012, namely how to reconcile the divergent views about the expansion of finfish farm development in the Marlborough Sounds. The study showed that there was a high degree of uncertainty over relevant knowledge and a lack of consensus on norms and values between stakeholders, indicating that finfish farm development in the Marlborough Sounds is an unstructured, or ‘wicked’ problem. The policy strategy best suited to solving this type of problem is a collaborative process that involves learning because it enables participants to identify, confront and integrate divergent viewpoints and knowledge. In doing this, participants reframe the policy problem and discover new opportunities for solving it. In this study, the greatest degree of diversity between viewpoints on finfish farm development was between industry stakeholders and others (iwi, non- government organisations, community members and governance and regulation representatives). The study highlights the need for the finfish farming industry to improve public understanding and gain support for its activities in order to achieve its growth and development goals. It also shows that, depending on the nature of the policy problems being addressed, collaborative planning processes could be adopted to manage conflicts about environmental resource use in settings other than freshwater in New Zealand.