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    Understanding attacks by kea (Nestor notabilis), an endemic parrot, on sheep (Ovis aries) in the South Island high country : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University/Te Kunenga ki Pūrehuroa, Manawatū, Aotearoa New Zealand
    (Massey University, 2019) Reid, Clio Elizabeth
    Human-wildlife conflict is a complex global issue that can have negative impacts on wildlife species and human livelihoods. An ongoing example of such conflict in Aotearoa New Zealand occurs between high country sheep farmers and kea (Nestor notabilis). This study is the first to document the conflict since attempts were made in the early 20th century. My aims were to: 1.) review the historical records of the conflict, and estimate the number of kea killed under a 100+ year bounty scheme; 2.) characterise sheep wounds attributed to kea attacks (‘kea strike’), and estimate the current prevalence and associated risk factors; 3.) survey high country farmers’ experiences with and perspectives of kea strike; 4.) examine behaviours that potentially underpin kea strike via experimental tasks presented to wild kea. I estimated that at least 116,869 kea were killed historically as a result of the bounty scheme. The majority of sheep wounds attributed to kea strike were in the loin (lumbar) region, and the wound prevalence was low (0–1.25%). However, it should be noted that the prevalence reported by farmers can be higher, and that higher kea strike frequency results in considerable economic and welfare costs for some high country sheep stations. Risk factors included station location, breed (Perendale), class (ram), and age (>1 yr). The results of an anonymous online survey of high country sheep farmers showed that less than half of the farmers reported kea strike, with low estimates of sheep injuries and losses, and a decrease of kea strike over the past 25+ years, which may have resulted from decreasing kea numbers and changes in sheep flock management. More than half of the farmers thought that only some kea attack sheep, which is consistent with the long-standing concept that kea strike is instigated by ‘rogue’ kea (problem individuals). Individual kea differed in innovative problem solving performance, exploration tendency and neophobia, and exploration tendency was linked with social rank and innovation. I propose that high ranking males that are innovative and exploratory may initiate kea strike. Understanding the drivers of kea strike can be used to inform conservation management decisions regarding farmer-kea conflict, to the benefit of kea, high country sheep farmers and their stock.
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    Innovative behaviours and personality traits in captive kea (Nestor notabilis) as a model for the emergence of kea strike in wild populations : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology, at Massey University, Manawatu, New Zealand
    (Massey University, 2017) Fancy, Jessica Sarah
    The personality traits of seven captive kea (Nestor notabilis) were investigated in terms of neophobia, problem solving ability, and innovation. The first objective was to compare the personalities of the birds and assess these in relation to demographic factors including age and sex, as well as looking at the effect of isolated versus group housing. Kea are known to require high standards of enrichment and sociality, so this information can be used to determine the effect their captive housing may have on important wild traits. The second objective was to observe whether particular personalities or demographic factors made a kea more innovative, or in this case more likely to attack a sheep. Kea strike is a phenomenon whereby kea attack sheep, which often die as a result. This conflict has led to approximately 100,000 kea being shot by farmers in retaliation, and as a consequence there has been a dramatic decline in the wild kea population. In order to assess each individual’s relative neophobia or neophilia, novel objects were presented to the kea and their reactions observed. Problem solving ability was measured by using a Multi-Access Box, which required the birds to use one of four different access routes to retrieve a food reward. To observe levels of innovation and the likelihood of kea strike emerging, a mechanical sheep analogue was used. This was made to resemble a sheep, and contained a food reward for the kea to find. The juveniles in this study were much more neophilic and adept at problem solving than the adults, and this is thought to be because juveniles are still learning about their environment and these traits are therefore highly beneficial to them. Only one juvenile successfully completed the sheep analogue task, and she was the most neophilic and adept at problem solving. This suggests that highly neophilic and explorative kea are more likely to develop innovative behaviours such as kea strike. Understanding the drivers behind kea strike is important if tools are to be developed to minimise the conflict in the future.
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    The ecology and anatomy of scent in the critically endangered kakapo (Strigops habroptilus) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology at Massey University, Auckland, New Zealand
    (Massey University, 2012) Gsell, Anna Clarissa
    The focus of the research presented here is the analysis of feather scent emitted by a parrot, the kakapo (Strigops habroptilus) and the kakapo’s ability to perceive scent by studying the anatomy of its brain and the olfactory bulb. In addition, behavioural research was conducted to determine the capability of the kakapo’s closest relatives, the kea (Nestor notabilis) and kaka (N. meridionalis) to detect scents and to distinguish between different concentrations of scents.The strong odour of the kakapo is one of the many unique characteristics of this critically endan-gered parrot, but its sense of smell has never been described in detail. The kakapo is the largest par-rot worldwide, it is nocturnal and flightless. Kakapo are herbivorous and it is the only parrot with a lek breeding system. Males defend several display arenas during the breeding season and continuously produce low frequency booming calls. Females come from afar and appraise different males and choose one with which they want to mate. As in all lek mating systems some males make major contributions to the gene-pool of the next generation while others make little or no contribution. Currently it is not known what the female’s choice is based on and why some male kakapo are ‘favoured’ over others. However, it has been observed that favoured males appear to emit a stronger odour than less attractive ones (pers. comm. Kakapo Recovery Team). This study is the first to compare the chemical composition of the kakapo’s scent in relation to season, age and sex. It is also the first study to uncover the kakapo’s ability to smell by conducting a comparative examination of the anatomy and histology of the brain and the olfactory bulb. In spite of its endangered status, the kakapo is a good model in which to study olfaction, as the birds are closely monitored by the Department of Conservation, New Zealand. The birds undergo regular health checks and transmitter changes, allowing access to a large proportion of the population at once and for which their individual history is known. The study of olfaction in kakapo is important as it can contribute to the growing field of avian olfaction, and by elucidating the kakapo’s potential for olfaction conservation managers will be able to make better decisions in their attempt to save this species. The research approach adopted in this dissertation includes the analysis of feather samples from individuals of different sex and age as well as from different seasons using gas chromatography-mass spectrometry. The opportunity to examine the brain as well as the eyes of a kakapo that died at Auckland Zoo, Auckland, New Zealand, allowed a comparative study of the brain, the olfactory bulb and the visual centres (of both the thalomofulgal and the tectogucal pathways) with other Australasian parrots. Additionally, behavioural experiments with kea and kaka, the closest relativesof the kakapo, give insight into two of New Zealand endemic parrot’s and their ability to distinguish between different scents and scents of different concentrations. The findings from this research provide evidence that kakapo distinguish themselves by having one of the largest olfactory bulbs measured in parrots and the highest number of mitral cells, responsible for the transmission of an olfactory neural signal into a behavioural response, counted in any species to date. They also have a strong odour, whose chemical composition shows sexual, age-dependent and seasonal distinction. Furthermore, the study found that kea and kaka are both able to distinguish between different scents and different concentrations of scents.The main conclusions drawn from this study are that kakapo appear to be equipped with a functional olfactory bulb, able to sense olfactory information, but also communicate information that is likely to be of social importance using their plumage scent. In conclusion, this dissertation provides the foundation for future research, in particular to examine the role of the scent in the social life in kakapo, and it provides fundamental insight into the olfactory and visual sensory abilities of the New Zealand endemic kakapo.
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    Lead exposure in free-ranging kea (Nestor notabilis), takahe (Porphyrio hochstetteri) and Australasian harriers (Circus approximans) in New Zealand : a thesis presented in partial fulfillment of the requirements for the degree of Masters of Veterinary Science in Wildlife Health at Massey University, Palmerston North, New Zealand
    (Massey University, 2009) Youl, Jennifer Marie
    Lead is a highly toxic metal that has been used by humans for over 2000 years. Over this time it has become increasingly apparent that despite its usefulness, lead is one of the most highly toxic substances known to man. Current research into lead exposure of humans focuses on low-level chronic exposure and its effects on learning and behaviour. However, investigations into lead exposure of wildlife are still focussed on mortalities, particularly of waterfowl and raptors, with little known about low-level exposures or the effects on other species. This study examines the exposure of free-ranging kea (Nestor notabilis) from the Aoraki/ Mt Cook village and national park, takahe (Porphyrio hochstetteri) from Tiritiri Matangi, Kapiti and Mana Islands, and the lead associated syndrome of clenched-claw paralysis and leg paresis in harriers (Circus approximans) in New Zealand. Thirty-eight kea had detectable blood lead with concentrations ranging from 0.028 mg/L to 3.43 mg/L (mean = 0.428 mg/L ± 0.581). Analysis of tissue samples found that seven of 15 birds died with elevated tissue lead. Lead exposure may be an important contributing factor in kea mortality. As a result of these findings, lead abatement in areas frequented by kea is being considered. Eighteen of 45 takahe had detectable blood lead concentrations ranging from 0.015 mg/L to 0.148 mg/L (mean = 0.028 mg/L ± 0.042). Analysis of tissue samples from offshore island and Murchison Mountains birds found that all had detectable lead. Despite levels of lead exposure in the population being low and unlikely to result in overt clinical signs, it is widespread and there may be significant exposure of birds living around old buildings. An investigation into the clinical signs, pathology and response to treatment of clenched-claw paralysis and leg paresis in wild harriers was carried out. Harriers with clenched feet had significantly higher blood lead concentrations than those without. In conclusion, lead is a major factor in the expression of this clinical syndrome but other factors not yet identified are playing a role. This study demonstrates that lead is widespread in the New Zealand environment exposing a diverse range of avifauna, and has made some progress towards exploring some of its effects on health and survival.