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There is limited biological and ecological data on hippos, most of which originates from riverine/lacustrine populations, with none on the Okavango Delta population in its unique wetland habitat. This thesis aimed to investigate the Delta’s hippo population (size/distribution) and examine small-scale seasonal variations in hippo pod dynamics, habitat selection, and behaviour. The research provides baseline ecological and behavioural data on hippos in wetland habitats and gives insight into their adaptability to changes in water availability. This is particularly important as the Delta’s waters are threatened by climate change and human pressure, which will reduce habitat for hippos.I utilised thirteen years of aerial survey data to examine temporal and spatial patterns of hippo populations in the Delta. Hippos preferentially occurred in large lagoons within seasonal swamps, avoiding the dense aquatic vegetation and deep water of the permanent swamp/main channels. Since the mid-1990s, Botswana’s hippo population has grown significantly, likely due to long-term increases in rainfall and inflow. The most recent survey (2018) emphasises Botswana as a stronghold for this species in Africa, however, the exceptionally small flood event of 2019 will likely have led to substantially reduced hippo numbers. This work demonstrates the value in long-term monitoring programs.I developed a method to monitor (count/age) hippos using a drone, achieving more accurate counts than ground and aerial surveys. Using this method, I examined seasonal changes in hippo pods (size/density/demographic composition/distribution) related to varying surface water availability. In the low flood season, hippos occurred in larger pods in higher densities, aggregating on the minimal water still available. All seasons were characterised by near-constant changes in pods, emphasising their dynamic nature and challenging the notion of stable hippo groupings.I conducted 24-hour activity budgets within the D

Northern Botswana is one of the giraffe strongholds across its geographic range in the absence of, or with low impact from, the major anthropological threats faced elsewhere. Yet despite its conservation significance, until now, no giraffe-specific ecological or behavioural studies have been undertaken. Moreover, Africa’s giraffe population has been significantly reduced over the last two decades, and the pressure on giraffe habitats and populations is likely to increase as the human population continues to expand, and the effects of climate change take their toll. As such, it is important to establish an ecological and behavioural baseline for giraffe in the unique ecosystems. This study provides baseline data on the behaviour and ecology of giraffe in the dry savannah and woodlands of the northern Chobe region and the wetland system of the Okavango Delta (NG26) in northern Botswana. The study first examines the home ranges, seasonal ranges and daily movements of giraffe in the two study areas. Next, the focus is on giraffe behaviours and activity budgets, and the effect of site, sex, season and time of day on behaviour. Lastly, the study describes the giraffe social grouping patterns in Chobe and examines non-random associations and spatial overlap as possible factors driving the population’s underlying fission-fusion system. Ecological and behavioural similarities were observed between the study areas, but also vast differences reflecting the adaptations made by giraffe in response to the unique set of environmental factors they face. Home ranges and daily movements were larger in Chobe where forage is more limited and patchily distributed, and ranges were larger during the dry season. Habitat, season, and sex were all found to be influential factors contributing to the observed variation in giraffe activity budgets. Social analyses revealed a complex social organisation whereby non-random associations and spatial overlap are drivers of a structured social networ

The most significant future threat to species is the loss of range and habitat as a result of human development. The aim of this thesis was to investigate elephant strategies in dealing with human-dominated landscapes, and to determine how best to manage the Botswana elephant population in the face of increasing human development. This thesis incorporated a number of different disciplines including GPS data, camera trapping, questionnaires and elephant behavioural observations, to gain a greater understanding of the “urban” elephant and how best to manage them.Elephant hourly and daily movement behaviour through different human dominated landscapes was found to be dependent on a variety of factors, including season, time of day and land use. It was revealed that elephants use narrow urban wildlife corridors within each human land designation. The results illustrate that urban wildlife corridors have proven to be useful tools in enabling elephants to pass through urban areas. The relative success of beehive fences as a potential elephant deterrent in Botswana was determined by assessing the response of the elephants to the sound of disturbed African honey bees. Family units showed a mixed response to both (Control/Bee) of the stimuli. 26.67 % of family units displayed a strong negative reaction to the bee playbacks, compared to 6.67% with the control playback. This study highlighted the importance of trialling the foundations of HEC deterrent before the implementation. Additionally in order to development successful species management the “people voice” must be assessed. This research presents a preliminary investigation of stakeholders’ opinions and perceptions of elephants and elephant management in Botswana. Results revealed people do value elephants for intrinsic reasons; however, there were concerns over the lack of management. These concerns of management may stem from the perceived block in communication flow between stakeholders as th

Details of the energy (food) requirements of domestic herbivores are essential for predicting grazing pressures and subsequent ecological impacts on rangelands. However, these details are lacking for some of the more recently introduced sheep breeds to Australia, such as the Dorper breed sheep, which are principally meat sheep, and it is uncertain how they compare with the traditional Merino, a wool-breed, sheep. We used the doubly labelled water method to compare the field metabolic rate and water turnover rate of Dorpers and Merinos grazing together in a small holding paddock in a typical rangeland environment. We found no significant differences in field metabolic rate (Dorpers 481 ± 125 kJ and Merinos 500 ± 109 kJ kg-0.73 day-1) or water turnover rate (Dorpers 397 ± 57 mL and Merinos 428 ± 50 mL kg-0.8 day-1). As such we conclude that under controlled conditions with limited movement and ready access to feed and water, dry sheep equivalent of 1 is appropriate for Dorpers (that is, one Dorper ewe had a grazing requirement equal to one standard, dry Merino wether). However, we also found that the field metabolic rate for Merinos under these conditions was only around half that measured in published studies for animals ranging freely in a large paddock system. This suggests that more work is needed to fully appreciate the energetic and grazing impacts of Dorpers versus Merinos under more realistic grazing conditions (e.g. large paddock systems) where feed and water are more spread. It also highlights limitations of the current dry sheep equivalent rating system, which has been derived from laboratory measures of sheep metabolic rates.

For over 50 years, kangaroos have been harvested commercially in Australia for their meat and skin and the practice is often the subject of much controversy. However, the animal welfare implications—particularly the impacts on dependent young—have not been extensively studied.In this thesis I describe research to investigate the effects of harvesting on kangaroo young and ways to potentially minimise animal suffering. My study consisted of five parts: (a) observing harvesting procedures and examining carcases to assess currently used methods for killing kangaroo young; (b) testing of a spring-powered captive bolt gun for killing pouch young; (c) determining the short-term welfare impacts of maternal separation on young-at-foot; (d) studying the attitudes and behavior of kangaroo harvesters using the theory of planned behavior; and (e) profiling the Australian public using audience segmentation methodology to identify groups that have different attitudes and perceptions about the management of kangaroos.I found that: (a) currently used methods of killing pouch young can be acceptably humane when they are performed correctly, although the techniques need to be standardised and harvesters require better training; (b) spring-powered captive bolt guns do not appear to deliver sufficient force to kill or even ensure acceptable levels of stunning of pouch young and hence testing with more powerful devices is recommended; (c) separated young-at-foot exhibit behavioural changes that indicate poor welfare; (d) some harvesters exhibit inconsistencies in their beliefs, attitudes and behaviour and also deficiencies in knowledge of kangaroos and humane harvesting practices; and (e) within the Australian public, there are three distinct groups with divergent views about kangaroo management and each group responds differently to messages on the topic.The results from this research can be used to directly improve the humaneness of current kangaroo harvesting practices and to inform

Fundamental differences in methane (CH4) production between macropods (kangaroos) and ruminants have been suggested and linked to differences in the composition of the forestomach microbiome. Using six western grey kangaroos (Macropus fuliginosus) and four red kangaroos (Macropus rufus), we measured daily absoluteCH4 production in vivo aswell asCH4 yield (CH4 per unit of intake of dry matter, gross energy or digestible fibre) by open-circuit respirometry. Two food intake levels were tested using a chopped lucerne hay (alfalfa) diet. Bodymass-specific absoluteCH4 production resembled values previously reported in wallabies and non-ruminant herbivores such as horses, and did not differ with food intake level, although there was no concomitant proportionate decrease in fibre digestibility with higher food intake. In contrast, CH4 yield decreased with increasing intake, and was intermediate between values reported for ruminants and non-ruminant herbivores. These results correspond to those in ruminants and other non-ruminant specieswhere increased intake (and hence a shorter digesta retention in the gut) leads to a lower CH4 yield.We hypothesize that rather than harbouring a fundamentally different microbiomein their foregut, the microbiome ofmacropods is in a particular metabolic state more tuned towards growth (i.e. biomass production) rather thanCH4 production. This is due to the short digesta retention time inmacropods and the known distinct 'digestawashing' in the gut of macropods, where fluids move faster than particles and hence most likely wash out microbes from the forestomach. Although our data suggest that kangaroos only produce about 27% of the body mass-specific volume of CH4 of ruminants, it remains to be modelled with species-specific growth rates and production conditions whether or not significantly lower CH4 amounts are emitted per kg of meat in kangaroo than in beef or mutton production.

Context: During commercial harvesting or non-commercial kangaroo culling programs, dependent young of shot females are required to be euthanased to prevent suffering and because they would be unlikely to survive. However, the current method for killing pouch young, namely a single, forceful blow to the base of the skull, is applied inconsistently by operators and perceived by the public to be inhumane. Aims: To determine whether an alternative method for killing pouch young, namely a spring-operated captive bolt gun, is effective at causing insensibility in kangaroo pouch young. Methods: Trials of spring-operated captive bolt guns were conducted first on the heads of 15 dead kangaroo young and then on 21 live pouch young during commercial harvesting. We assessed the effectiveness at causing insensibility in live animals and damage caused to specific brain areas. We also measured depth of bolt penetration and skull thickness. Performance characteristics (e.g. bolt velocity) of two types of spring-operated guns were also measured and compared with cartridge-powered devices. Key results: When tested on the heads of dead animals, the spring-operated captive bolt gun consistently produced a large entrance cavity and a well defined wound tract, which extended into the cerebrum, almost extending the full thickness of the brain, including the brainstem. When tested on live pouch young, the captive bolt gun caused immediate insensibility in only 13 of 21 animals. This 62% success rate is significantly below the 95% minimum acceptable threshold for captive bolt devices in domestic animal abattoirs. Failure to stun was related to bolt placement, but other factors such as bolt velocity, bolt diameter and skull properties such as thickness and hardness might have also contributed. Spring-operated captive bolt guns delivered 20 times less kinetic energy than did cartridge-powered devices. Conclusions: Spring-operated captive bolt guns cannot be recommended as an acceptable or hum