The hyoid apparatus in laryngeally echolocating bats is unique as it forms a mechanical connection between the larynx and auditory bullae which has been hypothesized to transfer the outgoing echolocation call to the middle ear during call emission. Previous finite element modeling (FEM) found that hyoid-borne sound can reach the bulla at an amplitude likely heard by echolocating bats; however, that study did not model how or if the signal could reach the inner ear (or cochlea). One route that sound could take is via stimulation of the eardrum – similarly to that of air-conducted sound. We used µCT data to build models of the hyoid apparatus and middle ear from six species of bats with variable morphology. Using FEM, we ran harmonic response analyses to measure the vibroacoustic response of the tympanic membrane to hyoid-borne sound generated during echolocation and found that hyoid-borne sound in all six species stimulated the eardrum within a range likely heard by bats. Although there was variation in the efficiency between models at higher frequencies, there are no obvious morphological patterns to account for it. This suggests that hyoid morphology in laryngeal echolocators is likely driven by other associated functions and warrants further inquiry. Note: This work was published open access in the Journal of Integrative Organismal Biology (https://doi.org/10.1093/iob/obad004)

京都大学 / 新制・課程博士 / 博士(情報学) / 甲第24936号 / 情博第847号 / 新制||情||142(附属図書館) / 京都大学大学院情報学研究科社会情報学専攻 / (主査)教授 大手 信人, 准教授 小山 里奈, 教授 三田村 啓理, 准教授 市川 光太郎 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

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My thesis focuses on different ranch management practices and the effects they may have on bird communities in northern Texas. Specifically, I address the potential differences between ranches enrolled in the Audubon Conservation Ranching program versus ranches that are not enrolled. Each research chapter is meant to be an individual publication. Chapter 2 compares and contrasts two different ways to survey bird communities in prairie systems. Chapter 3 compares ranch management techniques, prairie health indicators, and bird communities. This study aims to observe any mechanistic drivers of rangeland health that may elicit a positive bird assemblage response.

Acoustic communication in anurans plays a critical role in species recognition, defending territories and resources, and finding a mate. Anurans use a number of different call note types to communicate, from which the most notable are advertisement- and aggression calls. Optimum weather conditions are a precursor to the commencement of the breeding season for all frog species and their calling behaviour is therefore readily influenced by atmospheric conditions. Male frogs within a chorus also tend to call from territories within a specific range of distances from one another. The objectives of this study were to 1) determine a possible context in which call note types are produced, 2) to determine the effect of atmospheric conditions on calling behaviour and 3) to determine the spacing distances between males and females in a chorus of Queckett’s River Frog (Amietia quecketti). Pre-recorded note types were used in a playback experiment to determine a context for elicited responses. A context was derived for six of the responses. Advertisement (clicks and whines), aggression (creaks), encounter (tonal notes), territorial (whine-tonal notes), and release calls (squeaks) were described. Calls and atmospheric conditions were recorded and correlated for an entire breeding season. Water temperature, wind speed, humidity and barometric pressure had a significant effect on calling intensity. As water temperature decreased calling intensity increased, while increased wind temperature led to increased calling intensity. Amietia quecketti calls from the water, explaining the effect while increased wind speed decreases water temperature and can carry sound further. Both humidity and barometric pressure showed increased calling intensity only at specific levels. Humidity and barometric pressure have a direct effect on one another, which most likely causes the correlation between calling intensity and both these variables. In this study A. quecketti was shown to have breeding ponds for males and resting ponds and positions for non-gravid females. This prevents unwanted or unnecessary amplexus. Males showed much smaller and less variable territory sizes than females. This is most likely because males have a small range of optimal spacing distance while females move towards and away from males. The presence of vegetation resulted in smaller territories. This is possibly because smaller males act as satellite males and cannot be seen by larger males in vegetation. The size of males did not affect territory size. Males have a specific inter-male spacing distance regardless of size. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Globally urbanisation impacts on 88% of amphibian species and is recognised as a major cause for the observed amphibian declines. This is as result of habitat fragmentation, alteration in habitat morphology and degradation of habitat quality. The interference of anthropogenic noise on anuran communication and the impacts thereof on their breeding success has become a major research focus in recent conservation studies. . However, within the African continent very little research has been conducted on the effects of urbanisation on anuran habitat and the acoustic environment, which is the main focus of this study. The thesis is structured as follows: CHAPTER ONE provides an introduction to the field of urban ecology and relates it to amphibian conservation. The chapter reviews the far reaching and diverse effects of urbanisation on frog populations reported in literature across the world and also supply a broad introduction to the succeeding chapters. It also briefly summarises evidence from literature on the positive contributions brought about by the developed world. Following the vast negative impacts of urbanisation, the importance of amphibians is briefly discussed to motivate their conservation in urban environments, before concluding with a motivation for the need for urban ecological research on amphibians in South Africa. CHAPTER TWO addresses the distribution of amphibian communities across an urban-rural gradient in the city of Potchefstroom and assesses the habitat determinants explaining distribution at both local (pond) and landscape scales. Four surveys conducted spanned the breeding seasons of all species occurring in this region and included three different sampling techniques to detect fish and anuran larvae species. Seven micro-habitat and seven landscape variables were included to evaluate determinants of habitat use among local species and species richness. Using Bayesian modelling, aquatic vegetation, predatory fish and pond size was found to be major determinants shaping species richness on a local scale, whereas surface area of urban central business district had only a slightly negative correlation with species richness on a landscape scale. This is a pioneer study for documenting effects of urbanisation on amphibian communities along an urban-rural gradient in Africa. CHAPTER THREE evaluates the extent of the influence of aircraft acoustic noise on the calling behaviour of the critically endangered Pickersgill’s Reed Frog, Hyperolius pickersgilli. Literature documenting the effects of airplane noise on anuran calling activity is very limited and this study aimed not only to contribute to existing knowledge, but also to provide the first study of its kind within South Africa. Effects on five call properties of H. pickersgilli were determined using passive and directional recording equipment at two sites, reflecting presence and absence of aircraft flybys. Results showed an increase in calling rate of H. pickersgilli during aircraft flybys. Hyperolius pickersgilli was found to call throughout the night until just before sunrise. The calling behaviour, frequency structure and call sound pressure level of H. pickersgilli suggest that this species is prone to be effected by continuous anthropogenic noise. However, the lack of flights between midnight and sunrise provides a period of no disturbance for the frogs. Future studies on the effects of change in calling behaviour should be supported by playback studies at quiet sites and connected to breeding success to determine if these effects are detrimental to the survival of this critically endangered species. CHAPTER FOUR focussed on the Western Leopard Toad, Amietophrynus pantherinus and was divided into two major parts. One component focussed on the migration of this species across roads and aimed to firstly quantify the number of individuals migrating over a 500 m stretch of road using a drift fence system operated by public volunteers. The drift fence proved very successful, with no roadkill observed during the time it was in place. This study also stressed that large numbers of toads (average of 20.47% of 2 384 toads over six breeding seasons) are still being killed on the urban and suburban roads. Road patrol statistics collected by volunteers are biased in the sense that it is prone to human error, but when a drift fence is constructed, bias is excluded and space for human error limited. The study also provided road sensitivity areas analysed using geographic information systems to create digital buffer zones of 250 m, 500 m and 1 000 m around selected breeding sites. Secondly the study aimed to evaluate the use of data collected by these citizens occupying a volunteering role in the toad’s conservation. The second part of this study was directed towards the acoustic analysis of the call of A. pantherinus. The two main objectives of this component were to 1) evaluate the extent of variation of the call properties in order to 2) assess whether the ambient anthropogenic noise have an effect on these properties. Seven call properties for advertisement calls and four for release calls were analysed. Call properties were found to vary significantly between populations (P<0.05). Although sound pressure level was found to have an effect on variation by using canonical redundancy analysis, variation can also be explained by the geographical isolation of the populations. CHAPTER FIVE provided novel data on the extensive repertoire of Amietia quecketti in terms of its unique calling behaviour. Directional recordings were used to examine the extent of the variation in the two-part call (click-note followed by a whine-note). The whine-note was re-described and four different notes were designated, including the tonal-note, creak-note, pulsatile- / rip-note, and whine-note. Furthermore, the newly assigned whine-note was divided into nine phases that differed in frequency structure. Also, evidence is provided that A. quecketti males call at high frequencies. The success of A. quecketti in urban environments as observed in Chapter 2 is described in terms of this species’ extensive repertoire and unusual frequency structure. CHAPTER SIX provides insight into the effects of atmospheric conditions on the calling behaviour of Amietia quecketti, giving the proximate impact urbanisation has on weather conditions as well as the potential impact human activities can have on climate change on the long term. Calling activity was monitored over a nine-week period together with data from a mobile weather station which logged atmospheric variables every five minutes. Amietia quecketti was found to call most intensely between 00h00 and 03h00 in the morning and was most active in May, June and August. Humidity, temperature and wind velocity were found to have significant effects (P<0.05) on the calling activity of A. quecketti. CHAPTER SEVEN is concerned with the attitudes of people towards frogs in South Africa. The first part of this study assessed the attitudes of people towards frogs in Potchefstroom. Surveys were distributed via the internet as well as manually to reach people with no internet access as well. Attitudes of people of Potchefstroom were mostly positive with more than half of the sampled population of 295 respondents indicating a strong liking in frogs. This study provides evidence that the presence of myths and knowledge can highly affects people’s attitudes towards frogs. The second part of this study focussed on the motivations of volunteers saving Western Leopard Toads from roadkill in Cape Town, South Africa. Volunteers were motivated by a strong value-driven approach to saving toads. CHAPTER EIGHT provides a general discussion and outline on the contributions this study presented and also the new areas where more research is needed within the extent of the field of urban ecology from a South African perspective. / hD (Zoology), North-West University, Potchefstroom Campus, 2014

Acoustic communication in anurans plays a critical role in species recognition, defending territories and resources, and finding a mate. Anurans use a number of different call note types to communicate, from which the most notable are advertisement- and aggression calls. Optimum weather conditions are a precursor to the commencement of the breeding season for all frog species and their calling behaviour is therefore readily influenced by atmospheric conditions. Male frogs within a chorus also tend to call from territories within a specific range of distances from one another. The objectives of this study were to 1) determine a possible context in which call note types are produced, 2) to determine the effect of atmospheric conditions on calling behaviour and 3) to determine the spacing distances between males and females in a chorus of Queckett’s River Frog (Amietia quecketti). Pre-recorded note types were used in a playback experiment to determine a context for elicited responses. A context was derived for six of the responses. Advertisement (clicks and whines), aggression (creaks), encounter (tonal notes), territorial (whine-tonal notes), and release calls (squeaks) were described. Calls and atmospheric conditions were recorded and correlated for an entire breeding season. Water temperature, wind speed, humidity and barometric pressure had a significant effect on calling intensity. As water temperature decreased calling intensity increased, while increased wind temperature led to increased calling intensity. Amietia quecketti calls from the water, explaining the effect while increased wind speed decreases water temperature and can carry sound further. Both humidity and barometric pressure showed increased calling intensity only at specific levels. Humidity and barometric pressure have a direct effect on one another, which most likely causes the correlation between calling intensity and both these variables. In this study A. quecketti was shown to have breeding ponds for males and resting ponds and positions for non-gravid females. This prevents unwanted or unnecessary amplexus. Males showed much smaller and less variable territory sizes than females. This is most likely because males have a small range of optimal spacing distance while females move towards and away from males. The presence of vegetation resulted in smaller territories. This is possibly because smaller males act as satellite males and cannot be seen by larger males in vegetation. The size of males did not affect territory size. Males have a specific inter-male spacing distance regardless of size. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Globally urbanisation impacts on 88% of amphibian species and is recognised as a major cause for the observed amphibian declines. This is as result of habitat fragmentation, alteration in habitat morphology and degradation of habitat quality. The interference of anthropogenic noise on anuran communication and the impacts thereof on their breeding success has become a major research focus in recent conservation studies. . However, within the African continent very little research has been conducted on the effects of urbanisation on anuran habitat and the acoustic environment, which is the main focus of this study. The thesis is structured as follows: CHAPTER ONE provides an introduction to the field of urban ecology and relates it to amphibian conservation. The chapter reviews the far reaching and diverse effects of urbanisation on frog populations reported in literature across the world and also supply a broad introduction to the succeeding chapters. It also briefly summarises evidence from literature on the positive contributions brought about by the developed world. Following the vast negative impacts of urbanisation, the importance of amphibians is briefly discussed to motivate their conservation in urban environments, before concluding with a motivation for the need for urban ecological research on amphibians in South Africa. CHAPTER TWO addresses the distribution of amphibian communities across an urban-rural gradient in the city of Potchefstroom and assesses the habitat determinants explaining distribution at both local (pond) and landscape scales. Four surveys conducted spanned the breeding seasons of all species occurring in this region and included three different sampling techniques to detect fish and anuran larvae species. Seven micro-habitat and seven landscape variables were included to evaluate determinants of habitat use among local species and species richness. Using Bayesian modelling, aquatic vegetation, predatory fish and pond size was found to be major determinants shaping species richness on a local scale, whereas surface area of urban central business district had only a slightly negative correlation with species richness on a landscape scale. This is a pioneer study for documenting effects of urbanisation on amphibian communities along an urban-rural gradient in Africa. CHAPTER THREE evaluates the extent of the influence of aircraft acoustic noise on the calling behaviour of the critically endangered Pickersgill’s Reed Frog, Hyperolius pickersgilli. Literature documenting the effects of airplane noise on anuran calling activity is very limited and this study aimed not only to contribute to existing knowledge, but also to provide the first study of its kind within South Africa. Effects on five call properties of H. pickersgilli were determined using passive and directional recording equipment at two sites, reflecting presence and absence of aircraft flybys. Results showed an increase in calling rate of H. pickersgilli during aircraft flybys. Hyperolius pickersgilli was found to call throughout the night until just before sunrise. The calling behaviour, frequency structure and call sound pressure level of H. pickersgilli suggest that this species is prone to be effected by continuous anthropogenic noise. However, the lack of flights between midnight and sunrise provides a period of no disturbance for the frogs. Future studies on the effects of change in calling behaviour should be supported by playback studies at quiet sites and connected to breeding success to determine if these effects are detrimental to the survival of this critically endangered species. CHAPTER FOUR focussed on the Western Leopard Toad, Amietophrynus pantherinus and was divided into two major parts. One component focussed on the migration of this species across roads and aimed to firstly quantify the number of individuals migrating over a 500 m stretch of road using a drift fence system operated by public volunteers. The drift fence proved very successful, with no roadkill observed during the time it was in place. This study also stressed that large numbers of toads (average of 20.47% of 2 384 toads over six breeding seasons) are still being killed on the urban and suburban roads. Road patrol statistics collected by volunteers are biased in the sense that it is prone to human error, but when a drift fence is constructed, bias is excluded and space for human error limited. The study also provided road sensitivity areas analysed using geographic information systems to create digital buffer zones of 250 m, 500 m and 1 000 m around selected breeding sites. Secondly the study aimed to evaluate the use of data collected by these citizens occupying a volunteering role in the toad’s conservation. The second part of this study was directed towards the acoustic analysis of the call of A. pantherinus. The two main objectives of this component were to 1) evaluate the extent of variation of the call properties in order to 2) assess whether the ambient anthropogenic noise have an effect on these properties. Seven call properties for advertisement calls and four for release calls were analysed. Call properties were found to vary significantly between populations (P<0.05). Although sound pressure level was found to have an effect on variation by using canonical redundancy analysis, variation can also be explained by the geographical isolation of the populations. CHAPTER FIVE provided novel data on the extensive repertoire of Amietia quecketti in terms of its unique calling behaviour. Directional recordings were used to examine the extent of the variation in the two-part call (click-note followed by a whine-note). The whine-note was re-described and four different notes were designated, including the tonal-note, creak-note, pulsatile- / rip-note, and whine-note. Furthermore, the newly assigned whine-note was divided into nine phases that differed in frequency structure. Also, evidence is provided that A. quecketti males call at high frequencies. The success of A. quecketti in urban environments as observed in Chapter 2 is described in terms of this species’ extensive repertoire and unusual frequency structure. CHAPTER SIX provides insight into the effects of atmospheric conditions on the calling behaviour of Amietia quecketti, giving the proximate impact urbanisation has on weather conditions as well as the potential impact human activities can have on climate change on the long term. Calling activity was monitored over a nine-week period together with data from a mobile weather station which logged atmospheric variables every five minutes. Amietia quecketti was found to call most intensely between 00h00 and 03h00 in the morning and was most active in May, June and August. Humidity, temperature and wind velocity were found to have significant effects (P<0.05) on the calling activity of A. quecketti. CHAPTER SEVEN is concerned with the attitudes of people towards frogs in South Africa. The first part of this study assessed the attitudes of people towards frogs in Potchefstroom. Surveys were distributed via the internet as well as manually to reach people with no internet access as well. Attitudes of people of Potchefstroom were mostly positive with more than half of the sampled population of 295 respondents indicating a strong liking in frogs. This study provides evidence that the presence of myths and knowledge can highly affects people’s attitudes towards frogs. The second part of this study focussed on the motivations of volunteers saving Western Leopard Toads from roadkill in Cape Town, South Africa. Volunteers were motivated by a strong value-driven approach to saving toads. CHAPTER EIGHT provides a general discussion and outline on the contributions this study presented and also the new areas where more research is needed within the extent of the field of urban ecology from a South African perspective. / hD (Zoology), North-West University, Potchefstroom Campus, 2014

Le suivi des populations animales et végétales nous a amené à constater une perte importante de la diversité biologique. Les objectifs de la Convention sur la diversité biologique à atteindre pour 2010 sous-tendent la poursuite détaillée de ce suivi à l’échelle mondiale (CBD 2000). Cependant, il est difficile d’avoir une perception d’ensemble de la biodiversité d’un territoire, car les écosystèmes sont des entités dynamiques et évolutives, dans l’espace et dans le temps. Le choix d’un indicateur relevant de l’ensemble des ces caractéristiques devient donc primordial, bien qu’il s’agisse d’une tâche laborieuse. Ce projet propose d’utiliser la bioacoustique comme indicateur environnemental pour faire le suivi des espèces animales en milieu tropical. Afin de faire un suivi à une échelle régionale de la biodiversité, et ce, dans l’un des biomes les plus menacés de la planète, soit celui de la Mata Atlântica brésilienne, ce projet de recherche a comme objectif général de démontrer qu’il est possible d’associer la biophonie (événements sonores), à des événements biologiques (la richesse spécifique animale) en quantifiant des événements sonores (à l’aide des chants produits par les oiseaux, les insectes chanteurs de même que par les anoures) et en tentant de les associer aux fluctuations de la biodiversité. En plus de répondre à cet objectif général, trois objectifs spécifiques ont été définis : 1) comparer la biophonie et l’anthropophonie de milieux soumis à différents niveaux d’anthropisation ou de conservation afin d’évaluer l’impact anthropique sur le milieu, 2) évaluer la variabilité spatiale de la biodiversité, de même que 3) sa variabilité temporelle. Les résultats ont démontré que la biophonie est représentative de la biodiversité d’un milieu, et ce, même dans des conditions de biodiversité maximale puisqu’il existe une très forte relation entre les deux variables. De plus, les résultats révèlent une différence significative dans le ratio anthropophonie/biophonie de milieux soumis à différents niveaux de protection du territoire. La différenciation d’indices de puissance relative (dB/kHz) nous indique également l’importance de la variabilité spatiale et temporelle de la biodiversité, et par conséquent, l’importance de faire le suivi des espèces dans divers milieux et à diverses périodes afin d’obtenir une vision adéquate de la biodiversité régionale. / Recent monitoring of plant and animal populations has led us to observe a significant loss of global biodiversity. The objectives of the Convention on Biological Diversity for 2010 are to encourage environmental monitoring worldwide (CBD 2000). However, it is difficult to have an adequate portrait of the overall biodiversity of an area, because ecosystems are dynamic and evolving in both space and time. The choice of an indicator is therefore essential. This project proposes to use bioacoustics as an environmental indicator to monitor the animal biodiversity in tropical areas, in one of the most threatened biomes on the planet, the Mata Atlantica in Brazil. Our aim is to demonstrate that it is possible to relate biophony (sound events) to biological events (punctual animal species richness), i.e. to quantify songs produced by birds, insects and anurans singers and associate them to changes in biodiversity. In addressing this overall goal, three specific objectives were put forward: 1) compare the biophony and anthropophony of different landscapes, subjected to different levels of human occupation and conservation, in order to assess the human impact on the environment, 2) assess the spatial variability of biodiversity, as well as 3) its temporal variability. Results showed that biophony is representative of the biodiversity of an area, even under conditions of maximum biodiversity such as found in Brazil because there is a very strong positive relationship between these two variables. In addition, the results show a significant difference in the ratio anthropophony/biophony in environments subject to different human impacts. Disparate indices of relative power (dB / kHz) also reveal the importance of spatial and temporal variability of biodiversity, and therefore the importance of monitoring biophony in different environments and at different times to obtain an adequate portrait of a region’s biodiversity.