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    To disturb or not disturb : radio-telemetry based territory mapping and camera traps for monitoring cryptic species using Rakiura tokoeka (Apteryx australis australis) : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Conservation Biology at Massey University, Albany, New Zealand
    (Massey University, 2024) Feenstra, Emma
    Successful wildlife conservation is dependent on effective population monitoring. The objectives of monitoring can be multi-faceted, but population density is often coveted. However, estimating the density of species in which individuals cannot be identified is challenging without a complete census, which is rarely possible. In New Zealand, kiwi (Apteryx spp.) are morphologically and behaviourally cryptic species that are difficult to monitor, yet monitoring results are essential to their conservation. The gold standard of kiwi monitoring is territory mapping using radio-telemetry, yet this method had never been formally evaluated, and the alternative method is call counts, which are difficult to relate to population variables. Using Rakiura tokoeka (Apteryx australis australis) as my case study species, I implemented territory mapping with radio-telemetry at two novel locations on Rakiura/Stewart Island, one a pest-free island. My aim was to establish ‘known’ populations (minimum densities), and evaluate the traditional territory mapping method (Robertson, 2018) by comparing different ways of establishing territory boundaries (field-workers-estimates, convex 100% and concave polygons) and incorporating increasing numbers of locations by extending the length of the surveys. In these two study locations, and an additional two locations where historical territory mapping surveys of Rakiura tokoeka had provided minimum density estimates, I then trialled a novel method for monitoring kiwi populations, camera trap grids. I ran camera trap surveys for Rakiura tokoeka seasonally between 2018 and 2020 in the four locations, using the same study areas that were used for territory mapping. I used the data from the camera surveys in two ways, firstly for a relative abundance index (calculating camera trap rate), and secondly in a statistical abundance model that estimated point abundance and detection probability (Royle-Nichols, 2003). I also evaluated the use of radio-telemetry and camera traps for monitoring Rakiura tokoeka through the breeding season and providing information on the survival, growth, and dispersal of young Rakiura tokoeka. I found that territory mapping using radio-telemetry is an effective monitoring method for establishing minimum densities of Rakiura tokoeka, but that current methods could be improved. Convex polygon territory boundaries were similar to field-workers-estimate boundaries but could be applied more objectively and increasing the number of location fixes decreased density estimates. Camera trapping was an effective monitoring method for Rakiura tokoeka populations. Camera trap rates were an easy to apply index that is widely applicable to the many community and conservation groups working with kiwi that do not have access to radio-telemetry for monitoring. Camera trap rates indicated that the pest free island (Ulva Island) had lower detections of Rakiura tokoeka than the other three locations. This could have been due to lower densities of Rakiura tokoeka over some parts of the island, or lower detection probabilities. From the abundance model, estimates of density of Rakiura tokoeka at the four locations were not significantly different to those from territory mapping. This indicated that camera trap surveys could be used as a non-invasive alternative to territory mapping with radio-telemetry for Rakiura tokoeka, and potentially other kiwi species that has lower cost and requires less effort. I found the use of radio-telemetry and camera traps effective for monitoring different aspects of breeding behaviour, nesting, and chick variables, with the best use being a combination of the two methods. From the data collected on age structure, breeding and survival, I found no reason for immediate concern or management intervention for the Rakiura tokoeka population. This project shows the importance of questioning established methods, trialling new methods, combining methods, and considering whether the invasiveness of a method is warranted to meet the project objectives.
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    Investigation, design and fabrication of miniaturized CMOS novel active RFID tags : Doctor of Philosophy in Engineering-Electronics, Information and Communication Systems at Massey University, Albany campus
    (Massey University, 2021) Kumari, Meera
    The drastic decline in the bee population in the past few years is alarming given the quantity and quality of global food reliance on these insect pollinators. To ensure sustainable crop production and maintain biodiversity, it has become an important area of research for entomologists to study the factors involved in the dramatic population decline of these tiny insects. Understanding the insect’s biology and their foraging behavior tracking in the agricultural landscape is crucial. However, due to the large size of the available PCB-based tracking tags knowing their true behaviours in the presence of various chemical fertilizers and pesticides is still a challenge. In this research, a very new VHF radio telemeter architecture has been developed which could facilitate tracking of a large number of small insects and bees wirelessly in real-time at a distance of around 1km. The architecture is based on a novel circuit topology to generate an extremely low duty cycle signal digitally which for the first time does not require any passive elements. This digital generation technique of the low duty cycle has made it possible to realize the complete telemeter design on 1mmX 1mm ASIC chip, except for the antenna and the battery, and eliminated the need for discreet components which are mounted on PCB. Due to inconsistent fabrication facilities, the telemeter circuit parts were implemented in CMOS8RF-130nm and 8HPP-28nm, but the final ASIC telemeter prototype is realized in TSMC 65nm process technology and the fabricated chip is experimentally tested in the lab to verify its performance in the manufacturing environment. The design consists of a digital core circuit to generate 8-bit binary-coded 0.0078 duty-cycled burst mode signaling and a full on-chip analog power management circuit to locally generate the required voltage supplies with predefined dependence on temperature for the digital circuitry with the compensation for the temperature variation on the telemeter performance. A white paper calculation has been presented to package the insect telemeter ASIC, along with 10cm antenna directly over 80mg, 5mmX5mmX1mm silver oxide battery to yield a 95mg complete telemeter package, making it to be the world’s smallest and the lightest VHF radio telemeter.
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    Behaviour and activity budgeting of reproductive kiwi in a fenced population : a thesis presented in partial fulfilment of the requirements of the degree of Master of Science in Zoology at Massey University, Manawatu
    (Massey University, 2018) Robertson, Jillana
    North Island brown kiwi (Apteryx mantelli) are flightless, nocturnal, usually solitary, and secretive birds, so knowledge of their behaviour is limited. In this study, I endeavoured to obtain a more detailed understanding of adult kiwi behaviour within two pest fenced areas focusing around the breeding season at the 3363 ha Maungatautari Scenic Reserve in Waikato, New Zealand. Within Maungatautari’s pest free enclosures, I attempted to determine male and female activity patterns over 24-hours from activity transmitter data; document diurnal and nocturnal behaviours of kiwi using video cameras; determine size and distribution of home ranges; and establish patterns of selection of daytime shelter types. Male kiwi were fitted with Wild Tech “chick timer” transmitters which recorded activity for the previous seven days. Incubating males spent significantly less time active than non incubating males with some activity occurring during the daytime. Non-incubating male activity duration decreased but activity as a proportion of night length increased with decreasing night length. Less active incubating males, suggesting more time caring for eggs, had more successful clutches. Female activity was recorded using an Osprey receiver/datalogger and 30x60x90 pulse activity transmitters. Proportional activity was not correlated with night length and some female kiwi had extensive activity during the day which likely involved leaving their shelters. The occurrence of post-dawn activity was highly likely due to prior knowledge of feeding conditions. Efforts to obtain video footage of kiwi were only possible during daytime in shelters. Kiwi mostly slept during the day but they also scratched, stretched, preened, excavated, defecated, yawned, fed and sniffed. When a mate was present kiwi overall slept less. Mate preening was recorded for the first time. Significant differences in home range sizes were found between all male and female kiwi in both enclosures, and males and females in the southern enclosure. Home range overlap occurred only between females and unpaired birds. Shelter proximity to streams was significant, and reproductive status and water availability may be strong drivers determining home range location for Maungatautari enclosure kiwi. Dead vegetation matter and then underground cavities were the broad shelter types most used by kiwi and at a more detailed level, Windrows. Exploited Root Systems, Downed Logs, and Downed Masses were selected. Shelters were rarely re-used most likely due to an abundance of available shelters. Access to permanent water courses should be considered when considering habitat options for new kiwi populations as it helps ensure food availability. As well, the presence of abundant coarse woody debris creates high quality habitat for sheltering. Kiwi did not appear to be negatively impacted by the size of the enclosures at Maungatautari, and the population was healthy there during the course of this study.