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Item An investigation of causes of disease among wild and captive New Zealand falcons (Falco novaeseelandiae), Australasian harriers (Circus approximans) and moreporks (Ninox novaseelandiae) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University, Turitea, Palmerston North, New Zealand(Massey University, 2014) Mirza, VaseemInfectious disease can play a role in the population dynamics of wildlife species. The introduction of exotic birds and mammals into New Zealand has led to the introduction of novel diseases into the New Zealand avifauna such as avian malaria and toxoplasmosis. However the role of disease in New Zealand’s raptor population has not been widely reported. This study aims at investigating the presence and prevalence of disease among wild and captive New Zealand falcons (Falco novaeseelandiae), Australasian harrier (Circus approximans) and moreporks (Ninox novaeseelandiae). A retrospective study of post-‐mortem databases (the Huia database and the Massey University post-‐mortem database) undertaken to determine the major causes of mortality in New Zealand’s raptors between 1990 and 2014 revealed that trauma and infectious agents were the most frequently encountered causes of death in these birds. However, except for a single case report of serratospiculosis in a New Zealand falcon observed by Green et al in 2006, no other infectious agents have been reported among the country’s raptors to date in the peer reviewed literature. During the review of post-‐mortem records, organisms like Mycobacterium avium, Serratospiculum sp, Sarcocystis spp, Trichomonas galllinae and several unidentified helminths were identified as contributing or definite causes of mortality in all three species of raptors. But neither Plasmodium spp nor Toxoplasma gondii infections have been demonstrated in these birds so far. Therefore, a separate study was designed to determine the presence of these pathogens in New Zealand falcon, Australasian harrier and morepork tissues, using established molecular techniques. Molecular analysis of archived New Zealand raptor tissues confirmed the presence of both Plasmodium spp (10/117; 8.5%) and T. gondii (9/117; 7.7%) in all three species of raptors. Plasmodium strains identified were P. elongatum GRW6, P. sp AFTRU5, and P. relictum GRW4 and SGS1. Surprisingly, two Australasian harriers and one morepork tested for the presence of both Plasmodium spp and T. gondii as concomitant infections. However, it is unknown whether any of the positive tested birds suffered from clinical infections, since post-‐mortem records had no record of clinical signs of disease associated with either infections in these birds. Once the presence of the aforementioned pathogens among New Zealand raptors was established, an attempt was made to investigate their presence among live raptor populations as well. Blood samples were collected from raptors being admitted to Wildbase Hospital, Massey University, Palmerston North and Wingspan-‐ Birds of Prey Research Centre, Rotorua. Molecular analysis of these samples by PCR did not reveal the presence of Plasmodium spp in any of the ii tested birds, but one New Zealand falcon, Australasian harrier and morepork each tested positive for the presence of T. gondii. Interestingly, none of the positive birds showed any signs of clinical illness that may be associated with toxoplasmosis in raptors. We also analysed faecal samples and throat swabs from these birds to determine the presence of pathogens like Caryospora spp, Serratospiculum spp, Salmonella spp and T. gallinae, since many of these organisms have been detected in New Zealand and are also found affecting raptors in other parts of the world. However, apart from eggs resembling Capillaria spp, none of the other pathogens listed above were identified. My study has some limitations such as a small sample size and a geographic bias in terms of birds being submitted to Massey University, Palmerston North for post-‐mortem analysis. But this research may be regarded as the first report of Plasmodium spp and T. gondii infections among New Zealand’s three well-‐known raptor species and further research is required to determine the prevalence of these pathogens among the country’s total raptor population, pathogenicity of the organisms towards them and the role of these birds in the epidemiology of these diseases within New ZealandItem Avian raptor evolution : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Genetics, Institute of Fundamental Sciences, Massey University, New Zealand(Massey University, 2015) Mahmood, Muhammad TariqDespite decades of research using a variety of data sources (such as morphological, paleontological, immunological, DNA hybridization and short DNA sequences) both the relationships between modern avian orders of raptors and their times of origin remain uncertain. This prior work is discussed in the opening introductory chapter. In order to address these issues, the second chapter reports a study that I undertook to develop a database that would have all sequence data from avian raptors (although it could easily be modified for other groups as well). Complete mitochondrial (mt) genomes have been used extensively to help study evolution, and I sequenced seven new bird mt genomes: from owls, secretary bird, falcons, and eagles in order to provide improved taxon sampling for the avian raptors. Adding three of these taxa to the avian mt genome dataset aids in resolving deep bird phylogeny and strongly supports the independent origin of the raptor life-style – so there is now agreement between nuclear and mitochondrial sequences. The final four newer genomes were then added in for a more detailed analysis of raptor relationships, and good progress is made on this. We had issues with one of the final four newer genomes where the sample was mis-identified. Therefore, it is emphasized that it is always important to keep good reference samples to check identifications. For the fifth chapter I undertook a population level study of spotted owlet (Athene brama) a nocturnal raptor from Pakistan, and so my study includes the use of sequence data to study both micro- and macro-evolution. The final chapter is a current overview of where we are at now in relation to avian raptor evolution.