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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 Vocalisations of the New Zealand morepork (Ninox novaeseelandiae) on Ponui Island : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Zoology at Massey University, Palmerston North, New Zealand(Massey University, 2015) Brighten, AlexVocalisations provide an effective way to overcome the challenge of studying the behaviour of cryptic or nocturnal species. Knowledge of vocalisations can be applied to management strategies such as population census, monitoring, and territory mapping. The New Zealand Morepork (Ninox novaeseelandiae) is a nocturnal raptor and, to date, there has been little research into their vocalisations even though this offers a key method for monitoring morepork populations. Although not at risk, population monitoring of morepork will help detect population size changes in this avian predator which may prey on native endangered fauna and may suffer secondary poisoning. This study investigated the vocal ecology of morepork on Ponui Island, Hauraki Gulf, New Zealand from April 2013 to April 2014. The initial goal was to develop a monitoring method for morepork. However, due to a lack of detailed basic knowledge of their vocalisations, the primary objective shifted to filling that knowledge gap and providing baseline data for future research. The aims of this study were thus to characterise all of the calls given by the morepork on the island; to investigate spectral and temporal parameters of three main calls; to plot the amount of calling across a night and a year; and to study the responses of morepork to playback calls. Eight morepork were caught using mist-nets and subsequently tracked by radio-telemetry. Vocalisations were recorded using manual and automatic digital sound recorders and calls were analysed with manual and automated sound analysis software. I described eleven distinct calls, referred to as more-pork, trill, rororo, more-more-pork, weow, low trill, copulation squeal, single hoot, distress squeak, chicketting and juvenile begging trill and I further analysed the spectral and temporal characteristics of three main calls, more-pork, trill and rororo. I found variation between individual morepork in acoustic parameters of these call types. I found no evidence of sexual variation in the fundamental frequency, fundamental duration nor inter-syllable duration of the three call types. However, sample sizes were small (2 males to 7 females) and a larger sample size would be needed to confirm these results. The average number of all morepork call types showed temporal variation both nightly and monthly. A low amount of calling in winter months compared to summer appeared to coincide with the morepork breeding cycle. The highest numbers of call were heard from November to January, with the numbers of calls during this period being significantly higher than in all other months. The number of calls per hour showed two peaks: one around the middle of the night and the other during the last hour of darkness. The number of calls heard in the first two hours after sunset were significantly lower than during the rest of the night. Playbacks were effective in eliciting responses from morepork, but the proportion of responses to playback was lower than to natural calls. Response rates did not seem to be affected by season. Session time and order of playback had an effect on proportional responses as well as playback call-type whereby rororo elicited the most responses and trill elicited the fewest. This project broadened our knowledge of morepork vocal ecology and therefore contributes to our knowledge of raptor vocal communication. The study also presents information and recommendations that will be useful to future research and also in management of morepork. In particular, this project provides background information needed to help develop protocols for acoustic monitoring of morepork. The techniques used in this study and the general results can be used or applied to studies of other nocturnal species.