Bats (Chiroptera) are usually considered as a group greatly endangered by destructing their habitats through the human activity. However, a significant part of bat species at the central Europe use human buildings as shelters, moreover the natural shelters are marginal or unknown in several species. Considering the linkage of the great part of our bat species to the fragmented area and in connection with a long term human influence on the central european landscape we ask whether at least part of our species see human activity through providing proper shelters as positive. Based on the analysis of landscape structure and ruggedness effect on density, diversity and population structure of bat assamblages acquired by standardized mist net captures located in lowlands (elevations below 500 m) of Czech Republic (204 localities, 3585 bats, 22 bat species), we found that even though most of reactions were species specific and few species seemed to be positively associated with urban environments, most of the bat species rely on the broad-leaved forest cover and other natural habitats such as water bodies. The most significant factor influencing sexual segregation for bats was ruggedness of surrounding landscape. Keywords: Bats, Chiroptera, fragmentation, Europe, temperate zone

To avoid masking incoming echoes with outgoing calls, bats use a low duty cycle (LDC) or high duty cycle (HDC) echolocation strategy. LDC echolocation is the most common and involves short pulses of broadband sound followed by relatively long periods of silence. In contrast, HDC echolocators emit long, narrowband sounds with short periods of silence and use Doppler shifts to detect the relative speed of prey. HDC echolocators are almost exclusively found in the families Rhinolophidae and Hipposidaridae. However, there are two known exceptions that have evolved echolocation strategies independent of the families of which they reside: Pternotus parnelli is from an LDC family but uses HDC echolocation, and conversely, Coelops frithii is from an HDC family but uses LDC echolocation. In our previous work, we used engineering software to model sound transmission from the larynx to the auditory bulla via the stylohyal-tympanic bone articulation and found that sound transmitted through the bony chain during echolocation call emission is likely loud enough for bats to hear. We also noticed differences in the morphology of the stylohyal and its placement on the tympanic bulla that might correlate with echolocation strategy. Pteronotus parnelli and C. frithii, having evolved echolocation strategies that differ from the other species in their respective families, provide the opportunity to test whether these morphologies are simply “evolutionary baggage” or driven by a selective pressure associated with function. To test this, we used µCT image data to compare the morphology of the stylohyal bones from P. parnelli, C. frithii, and other LDC and HDC echolocators. Preliminary results show that HDC echolocators have a stylohyal that sits on the medial side of the bulla, while the stylohyal in LDC echolocators sits on the lateral side of the bulla. The stylohyal in P. parnelli and C. frithi appear to have characteristics of both HDC and LDC echolocators. Further analysis will include a Multivariant Functional Shape Analysis (MFSA) to determine if these morphological differences are statistically significant and identify what variant(s) are likely driving these differences. Lastly, digital 3D models from each bat species have been built from µCT data to test for functional differences via acoustic engineering simulations. Since bone conducted sound can reach the cochlea through direct stimulation or stimulation of the eardrum, we predict that an LDC echolocator, with its stylohyal sitting on the lateral side of the bulla, will transmit sound to the cochlea more effectively through the eardrum. And given the stylohyal in HDC echolocators sits on the medial side of the bulla, we expect to see better direct stimulation of the cochlea than that of a LDC echolocator. This research uses an integrative approach to address a long-held assumption concerning the function of the stylohyal-tympanic bone articulation in laryngeally echolocating bats.

The bat and human relationship has been one of ambiguity through the Anthropocene. Bats have been both persecuted and revered in different cultures and negative perceptions of bats remain widespread, causing concern for the support of bat conservation. Through this thesis I attempt to reach a better understanding of the interrelations between bats and humans, and the factors influencing perceptions of bats. This work lies in the interdisciplinary realm of animal studies, creating a junction between the natural and social sciences through studying and sharing the multispecies story of humans and bats. Through interviews and ethnographic study of bat researchers in Pretoria and an area of Limpopo Province, South Africa, attention is focused on the bat-human relationships from a South African context. A theme central to this work is human emotion, as I believe it is the greatest factor influencing how humans feel and act toward other beings. I examine how emotions towards certain stimuli, in this case bats, are formed through humans’ experiences and knowledge, looking at the different epistemic modes of knowing as other key concepts in this work while bringing attention to the emotional knowledge surrounding bats. Through a better understanding of the bat I believe the prevalent biophobia can transition into biophilia. Therefore, through this study I am to catch a glimpse into the meaningful lives of bats, striving to learn how to better know and understand them. Through this knowing I believe we can learn to love the bat for the unique animal it is, working towards securing the future of species and it’s environment in the midst of the current mass extinction, and hence secure the future of humankind as we move through the Anthropocene.

Historically, physiologists have believed steroid hormones act exclusively within the individual producing them. However, studies in mice have shown that bioactive 17β-estradiol (E2) is excreted in male urine and absorbed by female conspecifics where it binds to estrogen receptors in reproductive other tissues. This can lead to pregnancy disruption and/or cause precocious puberty in female conspecifics. In bats the transfer of tritium-labelled estradiol (3H-E2) from male to females has been shown during the mating season. I investigated the influence of season on 3H-E2 transfer and showed that females housed with 3H-E2 injected males had significantly higher levels of radioactivity in reproductive, neural, and peripheral tissues during reproductively relevant timepoints compared to the non-reproductive season. Because urine has been hypothesized as the vector of steroid hormone transmission in mice, I examined the natural patterns of sex steroids in the urine of male and female big brown bats (Eptesicus fuscus) across the annual reproductive cycle. I found that creatinine-adjusted E2, which corrects for animal hydration and activity, was significantly higher in male than female urine, and in adult compared to yearling urine. Seasonal differences in urinary E2 levels were observed within and between sexes. Finally, I designed a protocol to investigate the attractant properties of body odour and urine between bat sexes during the mating season. Using a two-alternative Y-maze arena, I found that female bats first approach the test arm containing urine of a male conspecific before exploring the arm with female urine. Females also tended to spend more time in the test-arm containing male urine and being in the male test-arm at the conclusion of the 5 min trial. My data supports the hypothesis that E2 has the potential to act as reproductive pheromone with urine as a likely vector. Given the close proximity of individual bats within a maternity roost, steroid hormone transfer between conspecifics quite likely occurs in nature and could have profound influences on female reproductive behaviour (e.g. receptivity) and physiology (e.g. estrus cycling). My research provides new evidence for the potential pheromonal actions of E2 in bats that is consistent with how sex steroids act as pheromones in other mammals. / Dissertation / Doctor of Philosophy (PhD) / Historically, physiologists have believed steroid hormones act exclusively within the individual producing them. However, studies in mice have shown that bioactive 17β-estradiol (E2) is excreted in male urine and absorbed by female conspecifics where it binds to estrogen receptors in reproductive and other tissues. This exogenous E2 can result in changes to female reproductive physiology and behaviour. Our lab has previously observed E2 to transfer between male and female captive big brown bats during the mating season. Research from this thesis provides evidence that the transfer of E2 from male to female bats is highest during times of mating and ovulation/fertilization. I also demonstrate that E2 naturally occurs in the urine of both male and females with age, sex, and seasonal differences in concentration. Lastly, I show that female bats are attracted to the urine of males. My research provides new evidence for the potential pheromonal actions of E2 in bats that is consistent with how sex steroids act as pheromones in other mammals.

Declining bat populations necessitates a need to understand how different land management techniques influence bat activity. This study assessed the influences of different coastal upland habitat management techniques, such as mulching, prescribed fire, and select cut, on forest bat activity within the Grand Bay National Wildlife Refuge and National Estuarine Research Reserve. Acoustic recorders were used to monitor bat activity and insect and vegetation surveys were used to assess influences on bat activity across different land management techniques. Results demonstrate that overall bat activity was similar across different land management techniques, however larger species adapted for open-space flying were shown to be less active within dense forest such as the select cut technique areas. Findings from this study suggest that various land management techniques can influence bat activity differently.

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)

No description available.

Human development continues to use up more physical space in the natural world, threatening the natural habitats of many organisms. To combat the loss of biodiversity science needs to explore what landscape features are important for different organisms so that we can incorporate these into the modern environment. As bats play an important role in many ecosystems and can reflect changes through trophic levels, analyzing their preferred habitats can help planners improve biological diversity of the urban habitat. Using acoustically identified bat sightings from Artportalen.se for the years 2017-2018, this paper studied the habitats of bats in Sweden. Through multiple regression analysis we examine the response in abundance and/or diversity of bats to physical and socio-cultural attributes of the urban habitat. We examined a total of 10160 bats from 18 species in 418 land cover locales and 306 demographical statistical areas with varying degrees of urbanization. Our results indicate that bat abundance and diversity decrease significantly with higher urbanization while deciduous forests are the most important land cover type for all bats. The results also indicate that wealthier areas have less abundance and diversity even when factoring in population density. Species specific analysis suggested that bat species who are better adapted at foraging in open vegetated landscapes and over water were less susceptible to the negative impacts of the urban habitat. We conclude that diverse habitats with a mixture of open vegetated areas, watercourses and broadleaf forests are the most important land features for a diverse bat fauna along with high connectivity via tree cover and linear landscape elements. If urban planning could incorporate these features into the urban habitat, some of the negative impacts of urbanization could be prevented.

Apesar dos morcegos hematófagos serem muito estudados, diversos aspectos de sua biologia e de seu papel na transmissão da raiva ainda não são conhecidos. O objetivo da presente tese foi estudar os abrigos diurnos, os agrupamentos e o comportamento agonístico do morcego hematófago comum, Desmodus rotundus, e sua relação com a raiva dos herbívoros no Vale do Paraíba. Foi possível também obter informações sobre as duas outras espécies de morcegos hematófagos, especialmente de Diphylla ecaudata. Entre 2011 e 2014, dados sobre abrigos diurnos, composição dos agrupamentos, lesões corporais, diagnóstico de raiva e sorologia antirrábica de D. rotundus foram obtidos nos municípios de Jacareí, Paraibuna, Pindamonhangaba, Salesópolis, Santa Branca e São Luiz do Paraitinga no Vale do Paraíba, Sudeste do estado de São Paulo, Sudeste do Brasil. Foram estudados 14 abrigos diurnos de D. rotundus, dos quais 12 eram construções abandonadas na área rural. Desmodus rotundus partilhou abrigos diurnos com apenas cinco espécies de filostomídeos: Diphylla ecaudata, Chrotopterus auritus, Carollia perspicillata, Glossophaga soricina e Anoura caudifer. O tempo de recolonização desses abrigos diurnos por D. rotundus foi em média 12,5 meses, com uma variação entre três e 25 meses. O tamanho dos agrupamentos variou de dois a 79 indivíduos, com uma média de 15,6 morcegos/grupo. Fêmeas foram encontradas em 15 agrupamentos, com uma média de 13 fêmeas e uma variação entre uma e 55 fêmeas/grupo. Por outro lado, machos estiveram mais presentes nos agrupamentos, ocorrendo em quase todos (N=21), com uma média de 7,1 machos/grupo e uma variação de um a 24 machos. Sete agrupamentos foram considerados de machos solteiros. Onze dos 22 agrupamentos eram constituídos de colônia e grupo de machos solteiros. O dimorfismo sexual no comprimento do antebraço de D. rotundus do Vale do Paraíba foi estatisticamente significativo e sugere que as fêmeas são maiores 13 do que os machos. Lesões corporais, atribuídas às mordeduras provocadas por outros morcegos, foram encontradas em 76,7 por cento dos indivíduos de D. rotundus, tanto em machos como em fêmeas. A região mais atingida foram as membranas alares, com 68 por cento , porém lesões nas orelhas, face e membros foram menos frequentes (23,1 por cento nas fêmeas e 26,9 por cento nos machos). Acredita-se que as lesões nessas regiões sejam mais importantes nos mecanismos de transmissão de raiva. Apesar de ter analisado 310 amostras de encéfalos de D. rotundus do Vale do Paraíba, o resultado foi negativo em todas as amostras. A sorologia mostrou que todos os morcegos apresentaram positividade em diferentes graus. Contudo, se considerarmos o ponto de corte 0,5 UI/ml, o número de indivíduos positivos caiu para 30,1 por cento (N=90), sendo 30,9 por cento nas fêmeas e 28,8 por cento em machos. Apesar de nenhum indivíduo de D. rotundus positivo para a raiva ter sido encontrado no Vale do Paraíba durante a presente tese, a sorologia positiva de, pelo menos, 30 por cento mostra que há vírus da raiva circulando em sua população. Essa alta circulação viral pode ter sido favorecida pelas interações agonísticas, que causam lesões em mais de 75 por cento dos morcegos, a formação compacta (em penca) dos agrupamentos, o grooming social, a reciprocidade e partilha alimentar / Despite the hematophagous bats are very studied, many aspects of their biology and their role in the transmission of rabies are not yet known. The aim of this thesis was to study the diurnal shelters, groups and the agonistic behavior of the common hematophagous, Desmodus rotundus, and its relation to the cattle rabies in the Paraíba Valley. It was also possible to obtain information about the two other species of vampire bats, especially Diphylla ecaudata. Between 2011 and 2014, data on diurnal shelters, composition of groups, body injuries, diagnosis of rabies and rabies serology D. rotundus were gathered from the cities of Jacarei, Paraibuna, Pindamonhangaba, Salesópolis, Santa Branca and São Luiz do Paraitinga in the Valley Paraíba, Southeastern of São Paulo State, Southeastern Brazil. Fourteen diurnal shelters of D. rotundus were studied here and 12 were abandoned buildings in rural areas. Desmodus rotundus shared daytime shelters with only five species of phyllostomid bats: Diphylla ecaudata, Chrotopterus auritus, Carollia perspicillata, Glossophaga soricina and Anoura caudifer. The time of recolonization of these roosts by D. rotundus was on average 12.5 months, ranging from three to 25 months. The size of the groups ranged from two to 79 individuals, with a mean of 15.6 bats/group. Females were found in 15 groups with an average of 13 females/group and ranging between one and 55 females. Moreover, males were present in most groups from Paraíba Valley, occurring in almost all (N = 21), with an average of 7.1 males/group, and a variation of 24 males. Seven groups were considered to be single males groups. Eleven of the 22 groups were made up of colony and single male groups. Sexual dimorphism in the forearm length of D. rotundus from the Paraíba Valley was statistically significant and suggests that females are larger than males. Body Injuries, attributed to bites caused by other bats were found in 76.7 per cent of individuals of D. rotundus, in both males and females. The most affected region was the wing membranes, with 68 per cent , but lesions on the ears, face and limbs were less frequent (23.1 per cent in females and 26.9 per cent in males). It is believed that injuries in these regions are more important in the rabies transmission mechanism. Despite having analyzed 310 samples of brains of D. rotundus from the Paraíba Valley, the result was negative in all samples. Serology showed that all bats were positive in varying degrees. However, if we consider the cut off 0.5 IU/ml, the number of positive samples dropped to 30.1 per cent (N = 90) and 30.9 per cent in females and 28.8 per cent males. Although no individual of D. rotundus positive for rabies was found in the Paraíba Valley during this thesis, the positive serology at least 30 per cent shows that there is rabies virus circulating in this bat population. This high viral circulation may have been favored by agonistic interactions, that cause lesions in more than 75 per cent of the bats, the compact formation (in clusters) of groups, social grooming, reciprocity and food sharing.

Apesar dos morcegos hematófagos serem muito estudados, diversos aspectos de sua biologia e de seu papel na transmissão da raiva ainda não são conhecidos. O objetivo da presente tese foi estudar os abrigos diurnos, os agrupamentos e o comportamento agonístico do morcego hematófago comum, Desmodus rotundus, e sua relação com a raiva dos herbívoros no Vale do Paraíba. Foi possível também obter informações sobre as duas outras espécies de morcegos hematófagos, especialmente de Diphylla ecaudata. Entre 2011 e 2014, dados sobre abrigos diurnos, composição dos agrupamentos, lesões corporais, diagnóstico de raiva e sorologia antirrábica de D. rotundus foram obtidos nos municípios de Jacareí, Paraibuna, Pindamonhangaba, Salesópolis, Santa Branca e São Luiz do Paraitinga no Vale do Paraíba, Sudeste do estado de São Paulo, Sudeste do Brasil. Foram estudados 14 abrigos diurnos de D. rotundus, dos quais 12 eram construções abandonadas na área rural. Desmodus rotundus partilhou abrigos diurnos com apenas cinco espécies de filostomídeos: Diphylla ecaudata, Chrotopterus auritus, Carollia perspicillata, Glossophaga soricina e Anoura caudifer. O tempo de recolonização desses abrigos diurnos por D. rotundus foi em média 12,5 meses, com uma variação entre três e 25 meses. O tamanho dos agrupamentos variou de dois a 79 indivíduos, com uma média de 15,6 morcegos/grupo. Fêmeas foram encontradas em 15 agrupamentos, com uma média de 13 fêmeas e uma variação entre uma e 55 fêmeas/grupo. Por outro lado, machos estiveram mais presentes nos agrupamentos, ocorrendo em quase todos (N=21), com uma média de 7,1 machos/grupo e uma variação de um a 24 machos. Sete agrupamentos foram considerados de machos solteiros. Onze dos 22 agrupamentos eram constituídos de colônia e grupo de machos solteiros. O dimorfismo sexual no comprimento do antebraço de D. rotundus do Vale do Paraíba foi estatisticamente significativo e sugere que as fêmeas são maiores 13 do que os machos. Lesões corporais, atribuídas às mordeduras provocadas por outros morcegos, foram encontradas em 76,7 por cento dos indivíduos de D. rotundus, tanto em machos como em fêmeas. A região mais atingida foram as membranas alares, com 68 por cento , porém lesões nas orelhas, face e membros foram menos frequentes (23,1 por cento nas fêmeas e 26,9 por cento nos machos). Acredita-se que as lesões nessas regiões sejam mais importantes nos mecanismos de transmissão de raiva. Apesar de ter analisado 310 amostras de encéfalos de D. rotundus do Vale do Paraíba, o resultado foi negativo em todas as amostras. A sorologia mostrou que todos os morcegos apresentaram positividade em diferentes graus. Contudo, se considerarmos o ponto de corte 0,5 UI/ml, o número de indivíduos positivos caiu para 30,1 por cento (N=90), sendo 30,9 por cento nas fêmeas e 28,8 por cento em machos. Apesar de nenhum indivíduo de D. rotundus positivo para a raiva ter sido encontrado no Vale do Paraíba durante a presente tese, a sorologia positiva de, pelo menos, 30 por cento mostra que há vírus da raiva circulando em sua população. Essa alta circulação viral pode ter sido favorecida pelas interações agonísticas, que causam lesões em mais de 75 por cento dos morcegos, a formação compacta (em penca) dos agrupamentos, o grooming social, a reciprocidade e partilha alimentar / Despite the hematophagous bats are very studied, many aspects of their biology and their role in the transmission of rabies are not yet known. The aim of this thesis was to study the diurnal shelters, groups and the agonistic behavior of the common hematophagous, Desmodus rotundus, and its relation to the cattle rabies in the Paraíba Valley. It was also possible to obtain information about the two other species of vampire bats, especially Diphylla ecaudata. Between 2011 and 2014, data on diurnal shelters, composition of groups, body injuries, diagnosis of rabies and rabies serology D. rotundus were gathered from the cities of Jacarei, Paraibuna, Pindamonhangaba, Salesópolis, Santa Branca and São Luiz do Paraitinga in the Valley Paraíba, Southeastern of São Paulo State, Southeastern Brazil. Fourteen diurnal shelters of D. rotundus were studied here and 12 were abandoned buildings in rural areas. Desmodus rotundus shared daytime shelters with only five species of phyllostomid bats: Diphylla ecaudata, Chrotopterus auritus, Carollia perspicillata, Glossophaga soricina and Anoura caudifer. The time of recolonization of these roosts by D. rotundus was on average 12.5 months, ranging from three to 25 months. The size of the groups ranged from two to 79 individuals, with a mean of 15.6 bats/group. Females were found in 15 groups with an average of 13 females/group and ranging between one and 55 females. Moreover, males were present in most groups from Paraíba Valley, occurring in almost all (N = 21), with an average of 7.1 males/group, and a variation of 24 males. Seven groups were considered to be single males groups. Eleven of the 22 groups were made up of colony and single male groups. Sexual dimorphism in the forearm length of D. rotundus from the Paraíba Valley was statistically significant and suggests that females are larger than males. Body Injuries, attributed to bites caused by other bats were found in 76.7 per cent of individuals of D. rotundus, in both males and females. The most affected region was the wing membranes, with 68 per cent , but lesions on the ears, face and limbs were less frequent (23.1 per cent in females and 26.9 per cent in males). It is believed that injuries in these regions are more important in the rabies transmission mechanism. Despite having analyzed 310 samples of brains of D. rotundus from the Paraíba Valley, the result was negative in all samples. Serology showed that all bats were positive in varying degrees. However, if we consider the cut off 0.5 IU/ml, the number of positive samples dropped to 30.1 per cent (N = 90) and 30.9 per cent in females and 28.8 per cent males. Although no individual of D. rotundus positive for rabies was found in the Paraíba Valley during this thesis, the positive serology at least 30 per cent shows that there is rabies virus circulating in this bat population. This high viral circulation may have been favored by agonistic interactions, that cause lesions in more than 75 per cent of the bats, the compact formation (in clusters) of groups, social grooming, reciprocity and food sharing.