Rozprawy doktorskie: „Insectivorous bat”

1

Hourigan, Clare. "Insectivorous Bat Diversity and Habitat Use in a Subtropical Mosaic Urban Landscape". Thesis, Griffith University, 2011. http://hdl.handle.net/10072/366401.

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Bats are an important component of global biodiversity as they are species-rich taxon. Urbanisation is thought to have a negative impact on diversity because of the destruction of large areas of natural habitat, which many species are unable to survive. A small number of studies on the ecology of insectivorous bats in urban areas have revealed that urbanisation has had a negative impact on bat diversity, but these studies were largely confined to compact Old World cities in temperate regions of the northern hemisphere. Contemporary patterns of urbanisation often create a mosaic of novel habitats, which may enable many species to co-exist within the same landscape. Few studies have investigated the factors affecting bat diversity or habitat use at multiple scales within the same city, and patterns of bat diversity in sprawling cities are poorly known. This study investigated the insectivorous bat diversity of Brisbane, Australia, a subtropical city in which rapid recent growth has created a sprawling mosaic of different urban land cover types. Specifically, the major aims of this study were to determine how patterns of α diversity and species composition (β diversity) of Brisbane’s urban bat assemblage varied among four major habitat types within the city: high density residential, low density residential, parkland and native bushland remnants. Each of these habitat types differed in the nature and extent of both tree cover and built structures. This study also investigated how these components contributed to urban landscape (γ) diversity, and how environmental characteristics at both local and landscape scales influenced observed patterns of habitat use by insectivorous bats. To obtain adequate information to address this study’s aims, effective and cost-efficient survey techniques were required. Previous studies comparing the effectiveness of different bat survey techniques have been conducted in forested rather than urban landscapes. As urban landscapes are distinctly different, survey methods that were effective in forested landscapes may not be so in urban landscapes. Therefore this study also compared the effectiveness of two methods, bat detectors and harp traps, for surveying the richness and composition of the urban bat assemblage.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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2

Grobler, Colyn Stefan. "Surveillance for rabies-related lyssaviruses in South African insectivorous bat species". Diss., University of Pretoria, 2021. http://hdl.handle.net/2263/78261.

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Lyssaviruses are bullet shaped negative-sense RNA viruses that are all able to cause the fatal encephalitic disease known as rabies. The genus currently consists of 17 formally recognised viral species with one tentative species awaiting classification. The prototype virus for the Lyssavirus genus is the well-known rabies virus (RABV), while all other species in the genus are classified as rabies-related viruses. In South Africa specifically, RABV, Lagos bat virus (LBV), Duvenhage virus (DUVV), and Mokola virus (MOKV) are known to circulate, with RABV and DUVV associated with human fatalities. Active surveillance on rabies-related lyssaviruses in bats, specifically African insectivorous bat species, is either very sporadic or non-existing, providing an inaccurate overall representation of prevalence, diversity, and geographic distribution. Therefore, we conducted viral nucleic acid surveillance for lyssaviruses in different insectivorous bat species in South Africa. These samples were collected during routine field surveillance and included bats that were found dead, appeared to be displaying abnormal behavior or taken as vouchers specimens as part of bat taxonomic studies. A quantitative real-time reverse transcription polymerase chain reaction assay, capable of detecting the diversity of lyssaviruses were used to test extracted RNA. Three brain samples tested positive and were further characterized by conventional RT-PCR, DNA sequencing and phylogenetic analyses targeting the nucleoprotein gene. One of the positive brains was detected from a Common slit-faced bat (Nycteris thebaica) and the other two positive brains were detected from the Natal long-fingered bat (Miniopterus natalensis). Phylogenetic analysis of the nucleoprotein indicated one detection to be a Duvenhage lyssavirus with the other two detections showing a close relationship with the West Caucasian bat virus species, previously only detected in Eastern Europe. However, a more than 20 % nucleotide divergence indicated it to be a potentially new lyssavirus species, Matlo bat lyssavirus. The virus was successfully isolated using the mouse inoculation test followed by full genome next generation amplicon sequencing. The results of the full genome characterisation further supported the initial findings with concatenated coding regions nucleotide divergence ranging between 16% and 23.7% as well as consistent phylogenetic tree topology groupings identical to initial phylogenetic analyses using multiple evolutionary models. The identification of a putative new lyssavirus highlights the importance of routine lyssavirus surveillance to understand the diversity. Further investigation is required to determine the possible reservoir species since the Natal long-fingered bats are known to co-roost with different bat species in caves. The potential of spillover to humans and other animals is unknown but people often enter these bat roosts for traditional and recreational purposes and bats do come into contact with several animal species including humans during foraging.
Dissertation (MSc)--University of Pretoria, 2021.
CDC- 5 NU2GGH001874-02-00 NRF-78566
Medical Virology
MSc
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3

Fan, Xiaozhou. "Canonical Decomposition of Wing Kinematics for a Straight Flying Insectivorous Bat". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/91469.

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Bats are some of the most agile flyers in nature. Their wings are highly articulated which affords them very fine control over shape and form. This thesis investigates the flight of Hipposideros Pratti. The flight pattern studied is nominally level and straight. Measured wing kinematics are used to describe the wing motion. It is shown that Proper Orthogonal Decomposition (POD) can be used to effectively to filter the measured kinematics to eliminate outliers which usually manifest as low energy higher POD modes, but which can impact the stability of aerodynamic simulations. Through aerodynamic simulations it is established that the first two modes from the POD analysis recover 62% of the lift, and reflect a drag force instead of thrust, whereas the first three modes recover 77% of the thrust and even more lift than the native kinematics. This demonstrates that mode 2, which features a combination of spanwise twisting (pitching) and chordwise cambering, is critical for the generation of lift, and more so for thrust. Based on these inferences, it is concluded that the first 7 modes are sufficient to represent the full native kinematics. The aerodynamic simulations are conducted using the immersed boundary method on 128 processors. They utilize a grid of 31 million cells and the bat wing is represented by about 50000 surface elements. The movement of the immersed wing surface is defined by piecewise cubic splines that describe the time evolution of each control point on the wing. The major contribution of this work is the decomposition of the native kinematics into canonical flapping wing physical descriptors comprising of the flapping motion, stroke-plane deviation, pitching motion, chordwise, and spanwise cambering. It is shown that the pitching mode harvests a Leading Edge Vortex (LEV) during the upstroke to produce thrust. It also stabilizes the LEV during downstroke, as a result, larger lift and thrust production is observed. Chordwise cambering mode allows the LEV to glide over and cover a large portion of the wing thus contributing to more lift while the spanwise cambering mode mitigates the intensification of LEV during the upstroke by relative rotation of outer part of the wing ( hand wing ) with respect to the inner part of the wing ( arm wing). While this thesis concerns itself with near straight-level flight, the proposed decomposition can be applied to any complex flight maneuver and provide a basis for unified comparison not only over different bat flight regimes but also across other flying insects and birds.
MS

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Thomas, Alicia Jessica. "Factors affecting the emergence times of seven sympatric insectivorous bat species". Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/12672.

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Includes bibliographical references (leaves 68-84).
The onset of activity in animals restricted to being active for only part of the day, is one of the most fundamental aspects of their biology. Onset of activity is likely subject to several factors including presence/absence of predators and the vagaries of environmental conditions at the time of emergence. The aim of my study was to test several hypotheses accounting for differing emergence times amongst sympatric insectivorous bat species.

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Cravens, Zachary. "ILLUMINATING DIETARY AND PHYSIOLOGICAL CHANGE IN AN INSECTIVOROUS BAT COMMUNITY EXPOSED TO ARTIFICIAL LIGHT AT NIGHT". OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2347.

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Global light pollution is increasing worldwide, nearly doubling over the past 25 years, and the encroachment of artificial light into remaining dark areas threatens to disturb natural rhythms of wildlife species, such as bats. Artificial light impacts the behaviour of insectivorous bats in numerous ways, including changing foraging behaviour and altering prey selection. I conducted two manipulative field experiments to investigate effects of light pollution on prey selection in an insectivorous bat community. In the first experiment, I collected fecal samples from 6 species of insectivorous bats in naturally dark and artificially lit conditions and identified prey items using molecular methods. Proportional differences of identified prey were not consistent and appear to be species specific. Red bats, little brown bats, and gray bats exhibited expected increases in moths at lit sites. Beetle-specialist big brown bats had a sizeable increase in beetle consumption around lights, while tri-colored bats and evening bats showed little change in moth consumption between experimental conditions. Dietary overlap was high between experimental conditions within each species, and dietary breadth only changed significantly between experimental conditions in one species, the little brown bat. Our results, building on others, demonstrate that bat-insect interactions may be more nuanced than the common assertion that moth consumption increases around lights. Thus, no single policy is likely to be universally effective in minimizing effects of light pollution on foraging bats because of differences in bat and insect communities, and their interactions. Our work highlights the need for greater mechanistic understanding of bat-light interactions to predict which species will be most affected by light pollution, and to more effectively craft management strategies to minimize unnatural shifts in prey selection caused by artificial lights. In the second experiment, I again focused on changes in foraging due to light pollution by investigating expected knock-on physiological effects, which have not been studied. I measured plasma ß-hydroxybutyrate concentrations from six species of insectivorous bats in naturally dark and artificially lit conditions to investigate effects of light pollution on energy metabolism. We also recorded bat calls acoustically to measure differences in activity levels between experimental conditions. Blood metabolite level and acoustic activity data suggest species-specific changes in foraging around lights. In red bats (Lasiurus borealis), ß-hydroxybutyrate levels at lit sites were highest early in the night followed by a decrease. Acoustic data suggest pronounced peaks in activity at lit sites early in the night. In red bats on dark nights and in the other species in this community, which seem to avoid lights, ß-hydroxybutyrate remained constant, or possibly increased slightly throughout the night. Taken together, our results suggest red bats actively forage around lights and may gain some energetic benefit, while other species in the community avoid lit areas and thus gain no such benefit. Our results demonstrate that artificial light may have a bifurcating effect on bat communities, whereby a few species benefit through concentrated prey resources, yet most do not. Further, this may concentrate light-intolerant species into limited dark refugia, thereby increasing competition for depauperate insect communities, as insects are drawn to artificially lit spaces. It appears then that artificial lights change the environment in such a way as to benefit some species in insectivorous bat communities.

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Rhodes, Monika, i n/a. "The Ecology and Conservation of the White-Striped Freetail Bat (Tadarida australis) in Urban Environments". Griffith University. Australian School of Environmental Studies, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070314.114451.

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Of all anthropogenic pressures, urbanisation is one of the most damaging, and is expanding in its influence throughout the world. In Australia, 90% of the human population live in urban centres along the eastern seaboard. Before European settlement in the early 1800s, much of the Australia's East coast was dominated by forests. Many of the forest dependent fauna have had to adapt to forest fragmentation and habitat loss resulting from clearing for urbanisation. However, relatively few studies have investigated the impact of urbanisation on biodiversity. This is especially true for the remaining fauna in large metropolitan areas, such as Melbourne, Sydney and Brisbane. The physical and conceptual context of this thesis is the increasing impact of urbanisation and the potentially threatening factors to forest dependent fauna. Bats were selected because they comprise a third of Australia's mammal species, and therefore form a major component of Australia's biodiversity. Very little is known about the ecology and conservation biology of hollow-dependent bats in general, but particularly in urban environments. The study was conducted in Brisbane, south-east Queensland, one of Australia's most biodiverse regions. More than a third of Australia's bat species occur in this region. A large insectivorous bat, the white-striped freetail bat (Tadarida australis), was selected to study two key resources in this urban area - hollow availability and foraging habitat. This thesis also examined if artificial roost habitat could provide temporary roosts for white-striped freetail bats and other insectivorous bats and assessed whether these bat boxes can be used as a conservation tool in urban environments where natural hollow-availability is limited. The white-striped freetail bat is an obligate hollow-dweller and roosted largely in hollows of old or dead eucalypts throughout Brisbane's urban matrix. These roost trees harboured significantly more additional hollow-dependent species compared to control trees of similar age, height, and tree diameter. Roost cavities inside trees often exceeded 30 cm in diameter. Furthermore, maternity colonies used cavities of hollow trunks, which often extended into major branches, to roost in big numbers. Therefore artificial alternatives, such as small bat boxes, may provide temporary shelter for small roosting groups, but are unlikely to be suitable substitutes for habitat loss. Although five bat species used bat boxes during this study, the white-striped freetail bat was not attracted into bat boxes. Roost-switching behaviour was then used to quantify associations between individual white-striped freetail bats of a roosting group. Despite differences in gender and reproductive seasons, the bats exhibited the same behaviour throughout three radio-telemetry periods and over 500 bat-days of radio-tracking: each roosted in separate roosts, switched roosts very infrequently, and associated with other tagged bats only at a communal roost. Furthermore, the communal roost exhibited a hub of socialising between members of the roosting group especially at night, with vocalisation and swarming behaviour not found at any of the other roosts. Despite being spread over a large geographic area (up to 200 km2), each roost was connected to others by less than three links. One roost (the communal roost) defined the architecture of the network because it had the most links. That the network showed scale-free properties has profound implications for the management of the habitat trees of this roosting group. Scale-free networks provide high tolerance against stochastic events such as random roost removals, but are susceptible to the selective removal of hub nodes, such as the communal roost. The white-striped freetail bat flew at high speed and covered large distances in search for food. It foraged over all land-cover types found in Brisbane. However, its observed foraging behaviour was non-random with respect to both spatial location and the nature of the ground-level habitat. The main feeding areas were within three kilometers of the communal roost, predominantly over the Brisbane River flood plains. As the only mammal capable of flight, bats can forage above fragmented habitats. However, as this study showed, hollow-dependent insectivorous bats, including free-tailed bats, are specialised in their roosting requirements. The ongoing protection of hollow-bearing trees, and the ongoing recruitment of future hollow-bearing trees, is essential for the long-term conservation of these animals in highly fragmented landscapes. Furthermore, loss of foraging habitat is still poorly understood, and should be considered in the ongoing conservation of bats in urban environments.

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7

Rhodes, Monika. "The Ecology and Conservation of the White-Striped Freetail Bat (Tadarida australis) in Urban Environments". Thesis, Griffith University, 2006. http://hdl.handle.net/10072/367292.

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Of all anthropogenic pressures, urbanisation is one of the most damaging, and is expanding in its influence throughout the world. In Australia, 90% of the human population live in urban centres along the eastern seaboard. Before European settlement in the early 1800s, much of the Australia's East coast was dominated by forests. Many of the forest dependent fauna have had to adapt to forest fragmentation and habitat loss resulting from clearing for urbanisation. However, relatively few studies have investigated the impact of urbanisation on biodiversity. This is especially true for the remaining fauna in large metropolitan areas, such as Melbourne, Sydney and Brisbane. The physical and conceptual context of this thesis is the increasing impact of urbanisation and the potentially threatening factors to forest dependent fauna. Bats were selected because they comprise a third of Australia's mammal species, and therefore form a major component of Australia's biodiversity. Very little is known about the ecology and conservation biology of hollow-dependent bats in general, but particularly in urban environments. The study was conducted in Brisbane, south-east Queensland, one of Australia's most biodiverse regions. More than a third of Australia's bat species occur in this region. A large insectivorous bat, the white-striped freetail bat (Tadarida australis), was selected to study two key resources in this urban area - hollow availability and foraging habitat. This thesis also examined if artificial roost habitat could provide temporary roosts for white-striped freetail bats and other insectivorous bats and assessed whether these bat boxes can be used as a conservation tool in urban environments where natural hollow-availability is limited. The white-striped freetail bat is an obligate hollow-dweller and roosted largely in hollows of old or dead eucalypts throughout Brisbane's urban matrix. These roost trees harboured significantly more additional hollow-dependent species compared to control trees of similar age, height, and tree diameter. Roost cavities inside trees often exceeded 30 cm in diameter. Furthermore, maternity colonies used cavities of hollow trunks, which often extended into major branches, to roost in big numbers. Therefore artificial alternatives, such as small bat boxes, may provide temporary shelter for small roosting groups, but are unlikely to be suitable substitutes for habitat loss. Although five bat species used bat boxes during this study, the white-striped freetail bat was not attracted into bat boxes. Roost-switching behaviour was then used to quantify associations between individual white-striped freetail bats of a roosting group. Despite differences in gender and reproductive seasons, the bats exhibited the same behaviour throughout three radio-telemetry periods and over 500 bat-days of radio-tracking: each roosted in separate roosts, switched roosts very infrequently, and associated with other tagged bats only at a communal roost. Furthermore, the communal roost exhibited a hub of socialising between members of the roosting group especially at night, with vocalisation and swarming behaviour not found at any of the other roosts. Despite being spread over a large geographic area (up to 200 km2), each roost was connected to others by less than three links. One roost (the communal roost) defined the architecture of the network because it had the most links. That the network showed scale-free properties has profound implications for the management of the habitat trees of this roosting group. Scale-free networks provide high tolerance against stochastic events such as random roost removals, but are susceptible to the selective removal of hub nodes, such as the communal roost. The white-striped freetail bat flew at high speed and covered large distances in search for food. It foraged over all land-cover types found in Brisbane. However, its observed foraging behaviour was non-random with respect to both spatial location and the nature of the ground-level habitat. The main feeding areas were within three kilometers of the communal roost, predominantly over the Brisbane River flood plains. As the only mammal capable of flight, bats can forage above fragmented habitats. However, as this study showed, hollow-dependent insectivorous bats, including free-tailed bats, are specialised in their roosting requirements. The ongoing protection of hollow-bearing trees, and the ongoing recruitment of future hollow-bearing trees, is essential for the long-term conservation of these animals in highly fragmented landscapes. Furthermore, loss of foraging habitat is still poorly understood, and should be considered in the ongoing conservation of bats in urban environments.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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8

Wood, Simon. "Geographic distribution and composition of the parasite assemblage of the insectivorous bat, Miniopterus natalensis (Chiroptera: Miniopteridae), in South Africa". Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/11224.

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Includes bibliographical references.
All free-living animal species have their own unique parasite assemblages. These parasites can have a significant impact on the fitness and ecology of their hosts, and through them the ecological systems in which they occur. Gaining knowledge about these parasites offers important information on the biology, systematics and phylogenies of their hosts. During this study the following were collected: flea, fly, mite, tick and helminth species from 96 Natal Long-Fingered bat (Miniopterus natalensis Smith, 1834) individuals sampled from seven localities across South Africa. This study aimed to both identify the species forming part of this parasite assemblage, and attempted to explain the distribution of the parasites and the factors influencing it.

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Shiflet, Lindsey Ann. "Trophic patterns of an insectivorous bat community foraging over urban and pristine streams as revealed by stable isotope and fecal analyses". Greensboro, N.C. : University of North Carolina at Greensboro, 2007. http://libres.uncg.edu/edocs/etd/1503Shiflet/umi-uncg-1503.pdf.

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Thesis (M.S.)--University of North Carolina at Greensboro, 2007.
Title from PDF t.p. (viewed Mar. 10, 2008). Directed by Matina C. Kalcounis-Rüppell; submitted to the Dept. of Biology. Includes bibliographical references (p. 24-29).

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Maine, Josiah J. "TROPHIC ECOLOGY OF INSECTIVOROUS BATS IN AGROECOSYSTEMS". OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1599.

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Land-use change is a leading cause of biodiversity loss and ecosystem service degradation worldwide, but these changes do not affect all organisms equally. Understanding the factors that influence resistance to environmental change is vital for informed conservation. In particular, dietary generalists may withstand environmental change better than specialists due to their ability to exploit variable resources. Bats are voracious predators of insects, but vary widely in their degree of dietary specialization. In Chapter 1, I analyze the effect of land cover and morphology on dietary diversity and the two most common prey items (Lepidoptera and Coleoptera) of bats, selecting important independent variables using phylogenetic generalized least squares (PGLS) and model selection. Dietary diversity increased with increasing amount of cropland near the study area, consumption of Lepidoptera decreased with increasing habitat diversity, and consumption of Coleoptera decreased with increasing distance from the equator. Biodiversity (and hence, prey diversity) is expected to decrease with agricultural intensity, but the observed pattern suggests that dietary specialists may avoid agricultural habitats due to lack of preferred prey. Dietary specialists may thus be increasingly at risk as agricultural intensity increases around the world, and it is essential that we continue to document their ecological roles and the services they provide to society

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Lumsden, L. F. "The ecology and conservation of insectivorous bats in rural landscapes". Click here to access, 2004. http://tux.lib.deakin.edu.au/adt-VDU/public/adt-VDU20050825.143504.

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Gonsalves, Leroy. "Saltmarsh, mosquitoes and insectivorous bats: Seeking a balance". Thesis, Australian Catholic University, 2012. https://acuresearchbank.acu.edu.au/download/f5003bcf6a9de158d56fd2d2c6990af12cd28e5c9dd04058be552ea89bd266f4/3702292/64882_downloaded_stream_107.pdf.

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Coastal saltmarsh provides suitable breeding habitat for a number of estuarine mosquito species. The saltmarsh mosquito (Aedes vigilax Skuse) can be locally abundant throughout summer, representing a potentially important prey resource for insectivorous bat species. However, Ae. vigilax has been identified as an important vector of mosquito-borne viruses such as Ross River virus and Barmah Forest virus and is a known nuisance biting pest. Coastal residential areas adjacent to Empire Bay (e.g., Killcare, Pretty Beach and Hardys Bay) on the Central Coast of New South Wales, Australia are prone to nuisance biting from Ae. vigilax and other estuarine mosquito species, particularly in late summer each year. Residents have requested use of a broadscale mosquito spraying regime (using Bacillus thuringiensis israelensis, Bti) to control numbers of Ae. vigilax. While it has been suggested that Ae. vigilax may be an important dietary item for insectivorous bats foraging within saltmarsh, no study to date has specifically investigated the importance of the mosquito in the diet of these bats. In this thesis, I investigated the importance of Ae. vigilax to insectivorous bats on the NSW Central Coast by examining relationships between bat activity, habitat use by bats, bat diet and the availability of Ae. vigilax and non-mosquito prey in three major habitats (saltmarsh, urban and forest) within the area. In all, 15 bat species and two species groups were recorded, of which eight are listed as threatened under the NSW Threatened Species Conservation Act (1995). Bats were most active in forest habitat, however, proportional feeding activity was greatest in saltmarsh. Positive relationships between prey abundance and total bat activity were only detected in the less cluttered saltmarsh habitat.

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Lumsden, Linda F., i mikewood@deakin edu au. "The ecology and conservation of insectivorous bats in rural landscapes". Deakin University. School of Ecology and Environment, 2004. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050825.143504.

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Throughout the world, the increasing use of land for agriculture has been associated with extensive loss and fragmentation of natural habitats and, frequently, the degradation of remaining habitats. The effects of such habitat changes have been well studied for some faunal groups, but little is known of their consequences for bats. The aim of this study was to investigate the ecology and conservation of an assemblage of insectivorous bats in a rural landscape, with particular focus on their foraging and roosting requirements. This increased knowledge will, hopefully, assist the formulation of policy and management decisions to ensure the long-term survival of bats in these altered environments. The distribution and abundance of insectivorous bats in the Northern Plains of Victoria was investigated to determine the impacts of land-use change and to identify factors influencing the distribution of bats in rural landscapes. Thirteen species of insectivorous bats were recorded across the region by sampling at 184 sites. Two species were rare, but the remaining 11 species were widespread and occurred in all types of remnant wooded vegetation, ranging from large blocks (≥200 ha) to small isolated remnants (≤5 ha) and scattered trees in cleared farm paddocks. There was no significant difference between remnant types in the relative abundance of bat species, in species richness, or in the composition of bat assemblages at study sites. In a subsequent study, no difference in the activity levels of bats was found between remnants with different tree densities, ranging from densely-vegetated blocks to single paddock trees. However, sites in open paddocks devoid of trees differed significantly from all types of wooded remnants and had significantly lower levels of bat activity and a different species composition. In highly cleared and modified landscapes, all native vegetation has value to bats, even the smallest remnant, roadside and single paddock tree. Roost sites are a key habitat requirement for bats and may be a limiting resource in highly modified environments. Two species, the lesser long-eared bat Nyctophilus geoffroyi and Gould's wattled bat Chalinolobus gouldii, were investigated as a basis for understanding the capacity of bats to survive in agricultural landscapes. These species have different wing morphologies, which may be influential in how they use the landscape, and anecdotal evidence suggested differences in their roosting ecology. Roosting ecology was examined using radio-tracking to locate 376 roosts in two study areas with contrasting tree cover in northern Victoria. Both species were highly selective in the location of their roosts in the landscape, in roost-site selection and in roosting behaviour, and responded differently to differing levels of availability of roosts. The Barmah-Picola study area incorporated remnant vegetation in farmland and an adjacent extensive floodplain forest (Barmah forest). Male N. geojfroyi roosted predominantly within 3 km of their foraging areas in remnants in farmland. However, most female N. geoffroyi, and both sexes of C. gouldii, roosted in Barmah forest up to 12 km from their foraging areas in farmland remnants. These distances were greater than previously recorded for these species and further than predicted by wing morphology. In contrast, in the second study area (Naring) where only small remnants of wooded vegetation remain in farmland, individuals of both species moved significantly shorter distances between roost sites and foraging areas. There were marked inter- and intra-specific differences in the roosts selected. C. gouldii used similar types of roosts in both areas - predominantly dead spouts in large, live trees. N. geoffroyi used a broader range of roost types, especially in the farmland environment. Roosts were typically under bark and in fissures, with males in particular also using anthropogenic structures. A strong preference was shown by both sexes for roosts in dead trees, and entrance dimensions of roosts were consistently narrow (2.5 cm). In Barmah forest, maternity roosts used by N. geoffroyi were predominantly in narrow fissures in large-diameter, dead trees, while at Naring maternity roosts were also found under bark, in buildings, and in small-diameter, live and dead trees. The number of roost trees that are required for an individual or colony is influenced by the frequency with which bats move between roosts, the proportion of roosts that are re-used, the distance between consecutive roosts, and the size of roosting colonies. Both species roosted in small colonies and regularly shifted roost sites within a discrete roost area. These behavioural traits suggest that a high density of roost sites is required. There were marked differences in these aspects of behaviour between individuals roosting in Barmah forest and in the fragmented rural landscape. At Naring, N. geqffroyi remained in roosts for longer periods and moved greater distances between consecutive roosts than in Barmah forest. In contrast, C. gouldii used a smaller pool of roosts in the farmland environment by re-using roosts more frequently. Within Barmah forest, there is an extensive area of forest but the density of hollow-bearing trees is reduced due to timber harvesting and silvicultural practices. Individuals were selective in the location of their roosting areas, with both species selecting parts of the forest that contained higher densities of their preferred roost trees than was generally available in the forest. In contrast, in farmland at Naring, where there were small pockets of remnant vegetation with high densities of potential roost sites surrounded by cleared paddocks with few roosting opportunities, little selection was shown. This suggests that in Barmah forest the density of trees with potential roosts is lower than optimal, while in farmland roosting resources may be adequate in woodland remnants, but limiting at the landscape scale since more than 95% of the landscape now provides no roosting opportunities. Insectivorous bats appear to be less severely affected than some other faunal groups by habitat fragmentation and land-use change. A highly developed capacity for flight, the spatial scale at which they move and their ability to cross open areas means that they can regularly move among multiple landscape elements, rather than depend on single remnants for all their resources. In addition, bats forage and roost mainly at elevated levels in trees and so are less sensitive to degradation of wooded habitats at ground level. Although seemingly resilient to habitat fragmentation, insectivorous bats are fundamentally dependent on trees for roosting and foraging, and so are vulnerable to habitat loss and ongoing rural tree decline. Protection of the remaining large old trees and measures to ensure regeneration to provide ongoing replacement of hollow-bearing trees through time are critical to ensure the long-term conservation of bats in rural landscapes.

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Lim, Lee Sim. "Assemblage and genetic structure of insectivorous bats in Peninsular Malaysia". Thesis, Queen Mary, University of London, 2012. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8544.

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Past climate change and recent human activity have had major impacts on the distribution of habitats as well as the community and population genetic structure of the species occupying these habitats. In temperate zones, glaciation forced many taxa into southern refugia. In contrast, little is understood about the extent to which tropical taxa and habitats were affected by colder periods. In Southeast Asia, some argue that the tropical forest was replaced by savannah at the Last Glacial Maximum (LGM), whereas others suggest that the forest persisted. Studying population genetic and community structure of forest-dependent species in this region may shed light on which of these scenarios is most likely, as well as provide crucial information on the effects of recent habitat loss. To address these issues, I studied the genetic and community structure of forest-dependent insectivorous bat species in Peninsular Malaysia. Data collected at 22 sites indicated that species richness declined with latitude, consistent with post-glacial expansion of forest. To test this further, I undertook mitochondrial DNA sequencing of a widespread species, Rhinolophus affinis, and found high haplotype diversity, little phylogeographic structure and no demographic growth. These all suggest a long population history in the region with no post-LGM range expansion. Subsequent microsatellite analyses of R. affinis and the congeneric R. lepidus showed that genetic distance followed an isolation-by-distance model, and that allelic diversity was unexpectedly higher in the northern populations. Taken together, my results from the community and genetic analyses disagree with each other. These conflicts are perhaps best explained if observed clines in species richness pre-date the LGM. I conclude that there is little evidence of forest contraction in the LGM. The fact that the highest species diversity was detected in the south, which is experiencing the most forest loss due to human activity, has important conservation consequences.

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Assis, Cecília Kruszynski de. "Diet and ecosystem services of insectivorous bats assessed with stable isotopes". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-07032019-103440/.

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Ecosystem services are natural environmental functions and ecological process that humans benefit from. In the present study, it was highlighted one of the services provided by bats: agricultural pest control. In Brazil, studies with insectivorous bats as potential pest suppressors are still scarce, despite the country being one of the biggest agricultural producers in the world and concentrating a high diversity of those animals. The use of heterogeneous landscapes, formed by native vegetation and crop fields, optimize the investment applied in this search. For that, it was described, for the first time, the bat assemblage in heterogeneous landscape in Piracicaba, at the campus \"Luiz de Queiroz\" that comprehends urbanized and agricultural areas, which provides many food resources for bats. Further, it was tested if there is difference in isotopic values (?13C and ?15N) between bat species related to diet, spatial foraging behavior, sex or taxonomic classification and which specie is a better pest suppressor. Bats were captured by mist nets and stable isotope analysis of carbon and nitrogen (?13C e ?15N, respectively) were used to access its food source. Through the analysis of ?13C and ?15N of insects, we determined the proportion of plants with photosynthetic cycles of C3 and C4 in bats\' diet and its trophic level. It was captured 90 bats of 11 species, three families and four dietary categories, corresponding to 66% of the total local richness estimated. From those, five are insectivorous species. Molossus molossus were the most abundant specie, followed by Artibeus lituratus and Glossophaga soricina. Carbon values showed that insectivores, frugivores and nectarivores consume insects, including pests, in different proportions per specie and diet group. Besides, ?15N values showed that bat trophic level were very similar, so bats are more generalist than usually assumed. This study points a need to quantify this important ecosystem service provided by bats that can reduce diseases and crop damages
Serviços ecossistêmicos são funções dos ambientes naturais e dos processos ecológicos dos quais humanos se beneficiam. Esses benefícios podem ser acessados por uma perspectiva econômica e ecológica. No presente estudo, nós destacamos um dos serviços ambientais fornecidos por morcegos: controle de pragas agrícolas. No Brasil, os estudos com morcegos insetívoros como potenciais supressores de pragas ainda são escassos, apesar de o país ser um dos maiores produtores agrícolas do mundo e abrigar uma alta diversidade desses animais. O uso de paisagens heterogêneas, formadas por vegetação nativa e lavouras agrícolas, otimiza o investimento aplicado nessa busca. Para tanto, descrevemos, pela primeira vez, a assembleia de morcegos em um ambiente heterogêneo de Piracicaba, o campus \"Luiz de Queiroz\", que possui desde áreas urbanizadas a agrícolas, disponibilizando diversos recursos alimentares para os morcegos. Ademais, testamos se há diferenças nos valores isotópicos (?13C e ?15N) entre as espécies de morcegos em relação à dieta, comportamento espacial de forrageamento, sexo ou classificação taxonômica para identificar quais grupos são os melhores supressores de pragas agrícolas. Utilizamos redes de neblina para a captura dos morcegos e análises de isótopos estáveis de carbono e nitrogênio (?13C e ?15N, respectivamente) para acessar sua fonte de dieta. Por meio das análises, determinamos a proporção de plantas com ciclos fotossintéticos do tipo C3 e C4 na dieta dos morcegos, bem como seu nível trófico. Capturamos 90 morcegos de 11 espécies, três famílias e quatro classes de dieta, correspondendo a 66% da riqueza estimada para o local. Destas, cinco são espécies classificadas insetívoras. Molossus molossus foi a espécie mais abundante, seguida por Artibeus lituratus e Glossophaga soricina. Valores de ?13C mostraram que insetívoros, frugívoros e nectarívoros consomem insetos, inclusive pragas, em diferentes proporções por espécie e grupo de dieta. O grupo mais efetivo no controle de pragas agrícolas foi M. molossus, seguido por A. planirostris. Os valores de ?15N mostraram que o nível trófico dos diferentes grupos alimentares de morcegos foi similar, de modo que eles são mais generalistas que previsto na literatura. Nosso estudo aponta a necessidade de quantificação desse importante serviço ecossistêmico promovido por morcegos, que podem reduzir doenças e prejuízos nas lavouras, além de combater vetores de doenças

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Estrada, Villegas Sergio. "Controlling factors of community structure: The case of neotropical aerial insectivorous bats". Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95176.

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In order to understand how communities are structured, it is necessary to determine which and how different factors control community properties across scales and how these community properties are related to one another. Working with neotropical insectivorous bat ensembles in Panama, we measured the effects of climate, habitat structure and insect resources at multiple scales on various community properties: composition, species richness abundance and feeding attempts. We then assessed how abundance, richness and biomass affected community evenness. We found that variation in species composition and richness are better explained by climate at larger scales and by habitat structure at smaller scales, respectively, but that total abundance is unrelated to climate. Evenness was directly and negatively correlated with species richness and biomass but indirectly and negatively correlated with abundance. Detecting how controlling factors affect community properties across scales and how community properties are interrelated can provide a better understanding of community structure.
Pour comprendre la façon dont les communautés sont structurées, nous devons déterminer l'effet des différents facteurs contrôlant les propriétés de communauté. Dans cette étude portant sur des ensembles néotropicaux de chauve-souris insectivores au Panama, nous avons mesuré les effets du climat, de la structure de l'habitat et des interactions entre espèces sur trois propriétés de communauté: la richesse, l'abondance et la biomasse des espèces. Puis, avons évalué comment ces facteurs affectent les mesures d'équitabilité. Nous avons trouvés que la variation dans la composition et la richesse en espèces est reliée au climat à grande échelle et à la structure de l'habitat à petite échelle, mais que l'abondance totale n'est pas reliée au climat. L'équitabilité corrèle de façon négative et directe avec la richesse et la biomasse en espèce et de façon négative et indirecte avec l'abondance. Nous concluons qu'il est important de déterminer l'échelle à laquelle les facteurs contrôlant opèrent et la façon dont les propriétés de communauté sont interreliées pour bien comprendre la structure des communautés.

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Roche, Niamh. "Aspects of the ecology of insectivorous bats (Chiroptera) in temperate deciduous woodlands". Thesis, University of Warwick, 1997. http://wrap.warwick.ac.uk/36308/.

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Ecological requirements of temperate bat species have been the subject of research in recent years. Remaining native woodlands are believed to be particularly important as foraging sites for bats in Britain. However, little work has been conducted on these habitats. This thesis examines spatial and temporal variations in bat activity in woodlands in relation to a number of factors including prey availability and diversity, weather variables and vegetation density. In this thesis, preference or avoidance of a woodland microhabitat was found to be related to vegetation density of the shrub and canopy. Optimal microhabitats balance the requirements for openness (related to a bat's morphology and echolocation capabilities) and a degree of shelter (necessary for predator avoidance). Nocturnal activity of Pipistrellus pipistrellus in woodlands was investigated and where the woodland was situated in close proximity to a roost, activity was unimodal during pregnancy, bimodal during lactation, and unimodal after weaning. However, in one woodland where no maternity roost was found close-by, nocturnal activity patterns differed. Seasonal bat activity within woodlands was examined in relation to insect availability and climatic factors. Activity was found to be mainly influenced by insect availability. The weather variables regulating insect abundance vary between woodlands and may largely be a function of site characteristics. The range and diversity of available prey taxa rarely affects activity of P. pipistrellus, the most commonly encountered bat in this study. Bat detectors have been used in many habitat and landscape studies (including this one) to estimate bat activity. Until now, no direct association has been made between the number of bat passes and the density of bats present. This issue was investigated using computer simulation models. A nonlinear relationship was found between bat passes and bat density, reducing to an almost linear relationship at the low bat pass numbers typically found in the field.

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Ades, Gary William John. "A comparative ecological study of insectivorous bats (Hipposideridae, Vespertilionidae and Rhinolophidae) in Hong Kong, with special reference to dietary seasonality /". [Hong Kong] : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B16121247.

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Andersson, Skog Nils. "Bats in Urban Sweden : A multiple regression analysis of bats’ relationship to urbanization". Thesis, Södertörns högskola, Miljövetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-45771.

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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.

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Ades, Gary William John. "A comparative ecological study of insectivorous bats (Hipposideridae, Vespertilionidae and Rhinolophidae) in Hong Kong, with specialreference to dietary seasonality". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31234033.

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Barreiro, Sílvia Pereira. "Saving trees for saving bats: tree-like features as key foraging habitats for insectivorous bats in intensively farmed agricultural lands". Master's thesis, Universidade de Évora, 2016. http://hdl.handle.net/10174/18418.

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The loss of natural vegetation remnants and homogenization of agricultural landscapes have detrimental effects on bat occurrence. As bats are efficient pest controllers, it is important to understand the mechanisms underlying their persistence in agricultural landscapes. By comparing structural features of increasing complexity (open fields, single trees, tree lines and woodlands), we investigated the patterns of bat species richness, flight and feeding activities; and the potential effect of prey availability on these patterns. Open fields were significantly less bat rich and had lower levels of flight and feeding activities than treed features, which were differently used by distinct bat guilds. These differences were not driven by prey availability, which was similar across structural feature complexity. We conclude that the occurrence of different structural elements within agricultural landscapes provide a variety of commuting and feeding habitats for bat species with different requirements, reinforcing the importance of landscape heterogeneity to bat occurrence and species richness in agricultural landscapes; PRESERVAR ÁRVORES PARA CONSERVAR MORCEGOS: ESTRUTURAS COM ÁRVORES COMO HABITATS DE ALIMENTAÇÃO CHAVE PARA MORCEGOS INSECTÍVOROS EM ÁREAS DE AGRICULTURA INTENSIVA. RESUMO: A perda de vegetação natural e a homogeneização das paisagens agrícolas tem efeitos negativos na ocorrência de morcegos. Devido ao importante serviço de controlo de pragas providenciado pelos morcegos, importa perceber os mecanismos subjacentes à sua persistência nestas paisagens. Neste estudo investigámos os padrões de riqueza específica e de actividade de voo e alimentação de morcegos em estruturas de complexidade crescente (campos abertos, árvores isoladas, linhas de árvores e bosques); assim como o potencial efeito da disponibilidade de alimento sobre esses mesmos padrões. Os campos abertos apresentaram menor riqueza específica e actividades de voo e alimentação em comparação com as restantes estruturas, que foram distintamente usadas por diferentes grupos funcionais. A ocorrência de morcegos não foi influenciada por diferenças de disponibilidade de alimento entre estruturas. Os resultados da nossa investigação sugerem que estruturas com distintos graus de complexidade providenciam uma variedade de habitats que facilitam a deslocação e oferecem oportunidades de alimentação para espécies com diferentes requisitos, corroborando a importância da heterogeneidade da paisagem para a ocorrência e riqueza de espécies de morcegos em paisagens agrícolas.

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Schoeman, M. Corrie. "The relative influence of competition and coevolution on the community structure of insectivorous bats in Southern Africa". Doctoral thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/6184.

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Includes bibliographical references (leaves 124-142).
Biotic filters rather than abiotic filters should influence the community structure of animals such as insectivorous bats with life histories characterized by low fecundity. low predation risk. long life expectancy, and stable populations. I investigated the relative influence of biotic filters on various parameters that define bat community structure, based on predictions from competition and coevolution hypotheses. Each of the competing hypotheses was considered from a number of different perspectives to provide multiple opportunities from which to uncover the mechanism that could result in non-random patterns of community structure. I used a battery of null model and multivariate analyses to test the deterministic or nondeterministic nature of phenotypic, trophic, and species composition patterns of insectivorous bat communities - which I called ensembles. I obtained data for these analyses by sampling the local and regional species richness of insecti vorous bats of southern Africa between 2001 and 2004. Rarefaction and species richness estimators indicated that species inventories of the fynbos, forest, and savanna ensembles, and the Cape Floristic Kingdom regional pool, were complete. As hypothesised, competition and coevolution filters strongly influenced parameters that define bat community structure. My results show that the phenotypic and trophic community structure of insectivorous bats at a local scale exhibit non-random patterns consistent with competition and coevolution hypotheses. Except for an even body size distribution, non-random patterns are not ubiquitous across ensembles. This is linked to multiple causations of competition and coevolution filters operating at a local scale. There was evidence that competition influenced body size distribution across ensembles, and echolocation and dietary patterns in ensembles with high species richness or abundance. At the same time, coevolution filters - mediated by prey defence - strongly influence dietary niche patterns. and to a lesser degree, echolocation patterns. Thus, the non-random phenotypic and trophic patterns of ensembles across southern Africa reflect competition and coevolution filters operating in tandem, or separately, at a local scale. Moreover, abiotic filters such as geographic distribution ranges of small and large-bodied species, extinction risk, and the physics offlight and sound probably also interacted at local and/or regional scales to influence the structure of coexisting bats at a local scale.

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Chaves, Luciana Botelho. "Produção de anticorpos monoclonais para caracterização de variantes antigênicas brasileiras de vírus da raiva". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/87/87131/tde-19082010-165840/.

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Anticorpos monoclonais (AcMo) contra proteínas do vírus da raiva (RABV) foram produzidos para adequar a caracterização antigênica dos isolados no Brasil. Foram selecionados dois isolados de morcegos insetívoros, sendo um de Nyctinomops laticaudatus e outro de Eptesicus furinalis que apresentaram perfis não compatíveis (NC) com os pré-estabelecidos. As suspensões virais foram adaptadas para crescimento em cultura de células N2A. Para o preparo de AcMo foram utilizadas como antígeno as ribonucleoproteínas dos isolados selecionados. Foram obtidos dois AcMo, o 3A7 e o 4E10. Analisando 57 isolados de RABV com esses AcMo, o 3A7 reagiu com 21 (36,84%) e o 4E10 com 25 (43,85%). Dos 13 isolados caracterizados como variante antigênica 3 (Desmodus rotundus) o 3A7 reagiu com 8 (61,53%) e o 4E10 com 11 (84,61%). Dos 9 isolados com perfil NC em morcegos o 3A7 reagiu com 5 (55,55%) e o 4E10 com 4 (44,44%). Os anticorpos produzidos poderão auxiliar na complementação do painel existente de caracterização antigênica o que poderá aprimorar a vigilância epidemiológica da doença.
Monoclonal antibodies (MAb) against the rabies virus (RABV) proteins were produced to improve the antigenic characterization of the isolates in Brazil. Two isolates from insectivorous bats were selected; one was from the species Nyctinomops laticaudatus and the other from Eptesicus furinalis, which showed non-compatible (NC) profiles from pre-established ones. The viral suspensions were adapted for growth in N2A cells. Ribonucleoproteins from selected isolates were used as antigen for the preparation of Mab. We obtained two Mab, the 3A7 and the 4E10. Of the 57 RABV isolates analyzed with these MAb, the 3A7 reacted with 21 (36.84%) and 4E10 with 25 (43.85%). Of the 13 isolates characterized as antigenic variant 3 (Desmodus rotundus), the 3A7 MAb reacted with 8 (61.53%) and 4E10 with 11 (84.61%). Of the nine isolates with the profile NC of bats the 3A7 reacted with 5 (55.55%) and the 4E10 with 4 (44.44%). The antibodies produced may help to complement the existing panel to antigenic characterization which could improve the disease epidemiological surveillance.

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Alem, Sylvain. "Du jeu des sélections chez une pyrale musicienne : étude de l'origine, de l'évolution et du maintien sélectif des comportements sexuels". Thesis, Tours, 2012. http://www.theses.fr/2012TOUR4042.

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Pour comprendre comment la sélection naturelle modèle les traits sexuels, l’emploi d’une approche intégrative des processus sélectifs en jeu semble aujourd’hui indispensable. Durant ma thèse je me suis ainsi intéressé aux influences simultanées des sélections de viabilité et sexuelle sur l’origine, l’évolution et le maintien des traits sexuels de la petite teigne de la ruche (Achroia grisella). Chez cette pyrale les mâles se regroupent en leks, produisent un chant d’appel ultrasonique intense et les femelles choisissent un partenaire sexuel en se basant sur des caractéristiques acoustiques spécifiques de ce chant. Cependant les signaux sexuels ultrasoniques des mâles peuvent également attirer des prédateurs : les chauves-souris insectivores. Ainsi, au sein des leks, les sélections sexuelle et de viabilité jouent et peuvent modeler (1) l’évolution du choix des femelles, (2) le maintien et l’évolution du lek, (3) l’origine de la communication acoustique sexuelle. Les travaux conduits durant cette thèse soulignent l’intérêt de l’étude du jeu des sélections sexuelle et de viabilité pour comprendre comment la sélection naturelle peut modeler l’origine, l’évolution et le maintien des traits sexuels. Les résultats indiquent en particulier le rôle crucial de la pression de prédation dans ces processus sélectifs
In order to achieve a better understanding of how natural selection shapes sexual traits it is essential to consider the interplay of the various selective processes at work. For my thesis I investigated the simultaneous influences of viability and sexual selections on the origin, the evolution and the maintenance of sexual traits in the lesser waxmoth Achroia grisella. Females of this pyralid moth choose their mate based on acoustic characters of the ultrasonic calling song broadcasted by males while competing at lek. However male ultrasonic displays are very conspicuous and may attract specific predators: insectivorous bats. Therefore at leks sexual and viability selection pressures act simultaneously and can shape (1) the evolution of female mate choice, (2) the maintenance and evolution of lekking, (3) the origin of sexual acoustic communication. Taken as a whole this work emphasises the relevance of the study of selective interplays between viability and sexual selections in order to improve our understanding of how natural selection may shape the origin, evolution and maintenance of sexual traits. In particular results indicate the crucial role played by predation pressure within these evolutionary processes

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"Spatial and Temporal Patterns in Insectivorous Bat Activity in River-Riparian Landscapes". Doctoral diss., 2010. http://hdl.handle.net/2286/R.I.8668.

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abstract: River and riparian areas are important foraging habitat for insectivorous bats. Numerous studies have shown that aquatic insects provide an important trophic resource to terrestrial consumers, including bats, and are key in regulating population size and species interactions in terrestrial food webs. Yet these studies have generally ignored how structural characteristics of the riverine landscape influence trophic resource availability or how terrestrial consumers respond to ensuing spatial and temporal patterns of trophic resources. Moreover, few studies have examined linkages between a stream's hydrologic regime and the timing and magnitude of aquatic insect availability. The main objective of my dissertation is to understand the causes of bat distributions in space and time. Specifically, I examine how trophic resource availability, structural components of riverine landscapes (channel confinement and riparian vegetation structure), and hydrologic regimes (flow permanence and timing of floods) mediate spatial and temporal patterns in bat activity. First, I show that river channel confinement determines bat activity along a river's longitudinal axis (directly above the river), while trophic resources appear to have stronger effects across a river's lateral (with distance from the river) axis. Second, I show that flow intermittency affects bat foraging activity indirectly via its effects on trophic resource availability. Seasonal river drying appears to have complex effects on bat foraging activity, initially causing imperfect tracking by consumers of localized concentrations of resources but later resulting in disappearance of both insects and bats after complete river drying. Third, I show that resource tracking by bats varies among streams with contrasting patterns of trophic resource availability and this variation appears to be in response to differences in the timing of aquatic insect emergence, duration and magnitude of emergence, and adult body size of emergent aquatic insects. Finally, I show that aquatic insects directly influence bat activity along a desert stream and that riparian vegetation composition affects bat activity, but only indirectly, via effects on aquatic insect availability. Overall, my results show river channel confinement, riparian vegetation structure, flow permanence, and the timing of floods influence spatial and temporal patterns in bat distributions; but these effects are indirect by influencing the ability of bats to track trophic resources in space and time.
Dissertation/Thesis
Ph.D. Biology 2010

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Grant, John D. A. "Aspects of the foraging strategy of an insectivorous bat, Nyctophilus gouldi Tomes, 1858 (Microchiroptera: Vespertilionidae)". Phd thesis, 1988. http://hdl.handle.net/1885/142327.

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Moonsamy, Shivani. "The relative influence of local and landscape processes on the structure of insectivorous bat ensembles in urban nature reserves". Thesis, 2012. http://hdl.handle.net/10413/9796.

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Urbanization is arguably the most damaging and rapidly expanding threat to biodiversity. The process of urbanization results in the fragmentation of natural habitat into patches that are disjunct and isolated from one another. Biogeography theory predicts that landscape processes, including fragment size and isolation, should predominate in species assembly. However, these predictions have not been tested on African bats in urban landscapes. Bats are important models for urban studies because they comprise more than a fifth of all mammals, and play vital roles as primary, secondary and tertiary consumers that support human-dominated ecosystems. Furthermore, there is evidence that local, biotic processes specifically competition and prey defences are important determinants of species composition patterns. In this study, I investigated the relative influence of local and landscape processes on the species composition patterns of insectivorous bat ensembles in Durban. Using active capture methods and passive monitoring, I sampled the insectivorous bat ensembles of eight nature reserves in Durban between 2008 and 2010. I used multivariate analyses to test predictions from biogeographic and climate hypotheses, and I used null model analyses to test predictions from competition and nestedness hypotheses to determine whether the bat richness patterns were significantly different from patterns expected by chance. Species richness estimators indicated that species inventories for ensembles were fairly complete (i.e. estimated species richness was not much larger than observed species richness). Multiple regression analyses showed that there was a significant parabolic relationship between species evenness and daily maximum temperature, and there was a significant negative relationship between relative activity and reserve shape. However, I found no evidence that competition influenced species composition patterns. Conversely, I found support for the nestedness hypothesis: species in species-poor ensembles were subsets of species in species-rich ensembles. Spearman rank correlation indicated that the degree of nestedness was significantly correlated with maximum temperature. My results suggest that in urban landscapes, abiotic processes operating at the landscape scale may be more important determinants of composition patterns of insectivorous bat species than biotic factors operating at a local scale. Furthermore, bat species that forage in cluttered habitats may not be able to persist in urban landscapes.
Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2012.

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Lai, Ching-Chang, i 賴慶昌. "Wing morphology of insectivorous bats in Taiwan". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/73140689774663279296.

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碩士
東海大學
生物學系
88
The wing morphology of bats is related to flying speed and habitat utilization. The purpose of this research was to study the relationships between wing morphology and flying speed of Taiwan''s insectivorous bats. In this study, by measuring the morphological characters to estimate wing loading and aspect ratio and to track 18 species of bat flights in the laboratory by videorecorder to calculate initial and free flying speed. The values of aspect ratio and wing loading were related to initial speed (r2=0.27, P<0.05; r2=0.85, P<0.01, respectively). When wing loading greater than 11N/m2, the mean value of free flying speeds will great than 5m/s. Of the 18 species of bats whose flying speed have been measured in this study: the free-tail bat, Tadarida sp. is the fastest one (7.06 m/s) and the slowest is the Formosan tailless leaf-nose bat, Coelops frithi formonsanus (2.98 m/s). Based on principle component analysis on 15 factors of bat wing morphology, and showed seven different wing forms in a digram of first and second principal components of wing morphology (identified as measures of wing loading and aspect ratio). By analysis wing loading and aspect ratio, the 22 species of bats showed four types of flight pattern. Bats will display faster flying speed when wing loading, and aspect ratio are large, as in free-tail bat, Formosan leaf-nose bat, Hipposideros terasensis; Bats will display migration when wing loading is smalll and aspect ratio is large, such as Japanese long-winged bat, Miniopterus schreibersii. From field observations, these fast flying species also appeared in open spaces. Bats have small wing loading and aspect ratio, will display slower flying speed, such as the Formosan lesser horseshoe bat, Rhinolophus monoceros, and Formosan tailless leaf-nose bat, Coelops frithi formonsanus will fly in cluttered habitats such as forests. Bats will display faster flying speed in cluttered habitats when wing loading is large and aspect ratio is small, such as Rhinolophus formosae.

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Marais, Werner Christiaan. "The potential of using insectivorous bats (Microchiroptera) as a means of insect pest control in agricultural areas". Thesis, 2010. http://hdl.handle.net/10210/3294.

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M.Sc.
Members of the Suborder Microchiroptera consume large numbers of insects. When large enough numbers of these bats are present in agricultural areas, the need for insecticides can be reduced significantly. The ZZ2 Tomato Farms in Mooketsi and the Secrabje Farm in Waterpoort, in the Limpopo Province were chosen as study sites. Although ZZ2 focuses on the production of tomatoes, both farms produce a variety of vegetables and fruit. These farms were chosen because the management of both have shown a commitment to conservation and attempt to minimise their impact on the environment. Bat species indigenous to the study areas were captured by means of mist nets for identification purposes. Basic morphological data of captured specimens were collected and recorded. Their roosting behaviour and preferences were studied by visiting diurnal roosts in the two study sites. Microclimatic measurements were taken in roosts occupied by Chaerephon pumilus, Mops condylurus and Taedarida aegyptiaca. Microclimatic measurements were also done in bat houses designed for the housing of bats in agricultural areas. Results suggest that other factors, additional to temperature and relative humidity, contribute to the success and probability of bat house occupancy by bats. Existing roosts in man-made structures such as roofs, can successfully be enhanced to stimulate increase in colony size. Bat activities were determined in agricultural areas and adjacent natural habitats by means of recordings of the echolocation calls of the different bat Families. These were compared to the occurrence of nocturnal flying insect orders that were captured in light traps at the same localities. Of the bat species studied, a positive correlation between increased bat activity and higher number of insects, including pest species, was found. It seems as if the Molossidae has the greatest potential to be utilised in the control of insect pests of agricultural areas in the Limpopo of the bat species studied. A holistic approach favouring insectivorous bats on farms is recommended. This can be done i.a. through the conservation of abundant areas of natural vegetation adjacent to the agricultural areas which would provide foraging for bats during winter, periods of drought or when the lands lie fallow. The excessive and injudicious use of insecticides, which has a negative effect on bats, counteracts the beneficial and cheap alternative of natural insect pest control provided by insectivorous bats.

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Turmelle, Amy S. "Ecological and Evolutionary Factors Affecting Rabies Virus Infection in Colonial Insectivorous Bats". 2009. http://trace.tennessee.edu/utk_graddiss/65.

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An introductory section provides a review for the role of bats as reservoirs of infectious diseases, and highlights the rationale for investigations of host life history, ecology, and evolution in regard to bat epizootiology. Chapter 1 presents field investigations of life history, ecology, body condition, and rabies virus neutralizing antibody seroprevalence in six natural colonies of Brazilian free-tailed bats from caves and bridge roosts in Texas. Chapter 2 presents a replicate field investigation of life history, ecology, body condition, and rabies virus neutralizing antibody seroprevalence in six natural colonies of Brazilian free tailed bats from bridges and bat house roosts in Florida and Georgia. Chapter 3 evaluates the relative influence of local and landscape factors on life history, ecology, body condition and rabies virus neutralizing antibody seroprevalence in Brazilian free-tailed bats in the southern United States. Chapter 4 describes the role of host population genetic structure in big brown bat rabies virus epizootiology, and describes comparative pathogenicity of two big brown bat rabies virus isolates across several captive experimental infection studies. The information presented has been used in the development of individual, population, and metapopulation models of rabies virus epizootiology in bats.

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Davidai, Noa. "Variation in the abundance of foraging insectivorous bats across an agricultural landscape". 2009. http://etd.utk.edu/2009/May2009Theses/DavidaiNoa.pdf.

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Jia-HueiChen i 陳佳惠. "Comparative food habits of two closely-related insectivorous bats and their eco-morphological correlates". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/67575391702948899310.

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碩士
國立成功大學
生命科學系
102
Ecological morphology presents constraints and opportunities to how animals explore resources by different mechanisms, and in turn may affect the resource use patterns of animals. Closely-related species with similar eco-morphological traits are presumably subjected to similar limitations, and thus are expected to explore similar resources. On the other hand, closely-related species may still display substantially different resource use, because slight differences in key eco-morphological traits may influence their performance and efficiency in exploring environments and resources. For microchiropterans, wing-shape parameters and echolocation structure often limit the type of habitats they are capable of exploring, which will affect the type of prey encountered. Body size, skull size, and tooth structure may further constrain size or hardness of prey consumed by bats. This study tested the hypothesis that small differences in crucial eco-morphological traits between congeneric species may contribute to different food habits. I conducted dietary analyses on fecal samples of two closely-related insectivorous bats, Hipposideros terasensis Kishida, 1924 and H. turpis Bangs, 1901, which were collected in their summer habitats. These two species differ in body size, skull size, and echolocation call frequency. I also measured related wing parameters, including span, area, and loading of wing, aspect ratio, tip length and area ratios of wing, and wingtip shape index, for these two species to compare their wing morphology. The diet of H. terasensis comprised of 9 insect orders, and that of H. turpis additionally included Araneae, Odonata, and Trichoptera and contained a total of 12 orders of arthropods. Both species fed primarily on Coleoptera that accounted for more than 20% in frequency of occurrence and about 40% in volume percentage, while the rest prey orders accounted for different proportions in their respective diets. Hemiptera and Hymenoptera accounted for 53.8% of the total frequency of occurrence and contributed to 50.8% of the volume in the diets of H. terasensis. In contrast, Orthoptera, Hemiptera, and Blattodea were more prevalent in the diet of H. turpis, but Orthoptera and Lepidoptera were more abundant in volumes. Below the level of order, I found 21 and 13 prey taxon, mostly families, in the diets of H. terasensis and H. turpis, respectively. Within hemipterans, H. terasensis consumed higher proportions of cicadas than H. turpis. Overall, H. terasensis displayed a more even and thus a more heterogeneous diet than that of H. turpis, with a medium dietary overlap between the two species at 0.67, based on Horn’s index of similarity. Most wing parameters measured were higher in H. terasensis than those of H. turpis. A higher wing loading and aspect ratio indicate a faster but less maneuverable flight for H. terasensis. In contrast, the flight of H. turpis is expected to be more maneuverable and adapted to near vegetation and the ground. In addition, H. turpis with higher call frequency would be more tolerant to cluttered environments. Incorporating the general flight potentials of insects, dietary results showed that H. terasensis, with higher wing loading and aspect ratio, consumed a higher proportion of faster-flying insects, such as Hymenoptera. The larger body and skull size of H. terasensis suggest a more powerful bite force, and the estimated hardness index of prey eaten by H. terasensis (3.75) was slightly higher than that of H. turpis (3.67). The food habits differed between H. terasensis and H. turpis in several aspects, and various factors might have contributed to these differences. The dietary results were consistent with the predictions from eco-morphological traits, including body size, wing parameters, and echolocation. Since H. terasensis ate more evenly among each insect order, it ate less number of insect orders but had a more heterogeneity diet. This study did not measure food availability on site, thus can’t rule out the possibility of dietary differences affected by prey availability. The dietary compositions of H. terasensis among sites across Taiwan, however, indicate little dietary variation in space and substantiate our conclusions. Eco-morphological traits constrain animals to explore resources and to a certain extent that have contributed to the different patterns of resource use, thus eco-morphological traits can be a good indicator for resource use patterns of animals with caution.

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Braun, de Torrez Elizabeth Claire. "Bats, insects and pecans: habitat use and ecosystem services of insectivorous bats in a pecan agroecosystem in central Texas". Thesis, 2014. https://hdl.handle.net/2144/15143.

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Comprehensive wildlife conservation strategies must include consideration of the agricultural matrix and its integration into the greater landscape. Bats are postulated to provide critical pest suppression services, but the effects of agricultural intensification on insectivorous bats are not clear. Few studies have thoroughly investigated the ecosystem services provided by bats due, in part, to limited understanding of species-specific habitat use in agricultural landscapes, difficulties in prey identification, and the challenge of quantifying the impact of bats on pest populations and crops. My dissertation integrates these components to describe ecological relationships between the insects and bats associated with a pecan agroecosystem in central Texas. Specifically, I focus on the predator-prey relationship between bats and the pecan nut casebearer moth (PNC), a devastating pest of pecans. I begin with a literature review of the ecosystem services of insectivorous bats and the data necessary to thoroughly evaluate these services. I then assess the potential factors influencing species composition and spatio-temporal distributions of bats within the pecan agroecosystem. My results demonstrate higher activity and diversity of bats within the pecan agroecosystem than in the surrounding landscape likely due to roosting opportunities, but species-specific and seasonal differences exist in the effects of management intensity. Next, I investigate direct interactions between bats and PNC by measuring prey consumption patterns. I found that five species of bats prey upon PNC moths during all three critical population peaks prior to insecticide application, but there is variability in consumption among species. Finally, I assess indirect interactions between bats and pecans, by evaluating the effect of bat predation risk on pecan damage by PNC larvae. A negative relationship between foraging activity by bats and both PNC moths and PNC larval damage to pecans provides evidence that bat predation has quantitative downstream effects. My results highlight the conservation value of the agricultural matrix for bats and the complexities of accurately documenting ecosystem services provided by free-ranging mobile organisms.

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López-Baucells, Adrià. "Assessment of the effects of forest fragmentation on aerial insectivorous bats in the Amazonian rainforest". Doctoral thesis, 2019. http://hdl.handle.net/10451/42288.

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Land use change and habitat fragmentation are among the most severe threats to biodiversity, especially in the tropics. In the Amazon, the abandonment of formerly deforested areas allowed the expansion of secondary regrowth, a type of habitat where bats are known to provide important ecosystem services. Amongst them, aerial insectivorous bats have been neglected in most Neotropical studies and remain poorly studied. However, the current upsurge in acoustic technology makes them easy targets to be monitored using ultrasound detectors. The aim of this thesis was to reveal the diversity of aerial insectivorous bats and quantify the effects of forest fragmentation on this ensemble within the Biological Dynamics Forest Fragments Project, a whole ecosystem experiment in the Amazon, currently composed of a mosaic of unflooded rainforest with continuous forest, and forest fragments embedded in a matrix of secondary regrowth. As part of this thesis, the first “Field Guide to the Bats of the Amazon” was published. A custom-built classifier was developed which was able to identify a large proportion of files to sonotype level (with > 90% accuracy), leaving the rest (<25%) to be manually classified. I also tested 20 different recording schemes and provided guidelines to optimize protocols for acoustic studies. In forest fragments and their adjoining secondary forests, taxonomic, phylogenetic and functional α diversity became gradually poorer with decreasing fragment size. In terms of β diversity, bat assemblage composition in secondary forests after ~30 years of recovery was still significantly different from that in continuous forest. However, forest edges harboured highly diverse bat assemblages due to the opening of cluttered areas, and the increase of less-sensitive species. Responses towards fragmentation were species-specific and strongly related to their functional traits. The results of this thesis highlight the irreplaceable value of tropical primary forests due to the long time required to recover fragmented ecosystems.
Fundação de Amparo à Pesquisa do Estado do Amazonas [FAPEAM 062.01173 / 2015] (Paulo ED Bobrowiec)
Bolsa de estudos do CNPq [160049 / 2013-0] (Paulo ED Bobrowiec)

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Pavón, Ana Daniela Sansur. "Exposure Assessment of Metals in Cave Dwelling Bats". Master's thesis, 2018. http://hdl.handle.net/10316/86210.

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Dissertação de Mestrado em Ecologia apresentada à Faculdade de Ciências e Tecnologia
Populações de morcegos estão em declínio pelo mundo. As principais razões desse declínio foram atribuídas à influência antrópica, incluindo alterações climáticas, urbanização, atividades agrícolas e industriais. As atividades humanas causam o deslocamento das colónias de morcegos de cavernas e outras de outros abrigos naturais para minas abandonadas. Devido a isso, as minas tornaram-se áreas de interesse para a conservação de morcegos cavernícolas em todo o mundo. As bem documentadas propriedades persistentes dos metais em todos os compartimentos ambientais (bióticos e abióticos) podem comprometer as espécies que vivem nas minas, mesmo após o término das operações de extração. Assim, o objetivo deste estudo é entender se morcegos que habitam em minas abandonadas estão expostos a metais. Amostras não invasivas de pelo, membrana alar e guano de 140 indivíduos de quatro espécies de morcegos insetívoros e cavernícolas (R. ferrumequinum, R. euryale, R. hipposideros e M. schreibersii) foram coletadas em quatro minas abandonadas de extração de metais na região Norte e Centro de Portugal. Estas minas são utilizadas como locais de hibernação para as espécies de morcegos estudadas. Adicionalmente, amostras de solo, rocha e água foram também coletadas de cada mina para avaliar as possíveis vias de exposição. As amostras foram avaliadas em termos das concentrações de 13 metais essenciais e não essenciais (As, Ag, Cd, Co, Cr, Cu, Mn, Ni, Pb, Se, Zn, Sn e W) usando ICP-MS. Elevadas concentrações de metais foram encontradas nas quatro espécies de morcegos, tanto na membrana alar como no pelo, confirmando sua exposição aos metais. Concentrações mais altas foram encontradas na membrana alar do que no pelo. Foram encontradas diferenças entre M. schreibersii e as restantes espécies estudadas, com esta espécie a apresentar as maiores concentrações de metais. As diferenças entre as espécies podem ser explicadas pelas diferenças no comportamento de alimentar e no uso do habitat, ligadas às áreas urbanas e ao conteúdo de metais encontrados no solo. No entanto, os resultados não permitiram identificar as vias de exposições de forma conclusiva. Em comparação com outros estudos, as concentrações encontradas em morcegos cavernícolas foram maiores do que nas espécies de morcegos com outras preferências em termos de locais de hibernação e reprodução. Os resultados reforçam a importância da monitorização de metais em espécies cavernícolas que utilizam minas como abrigo, uma vez que exposição a metais constitui um risco potencial para estas espécies de morcegos.
Bat populations seem to be decreasing all over the world. The main reasons for the decline have been attributed to anthropogenic influence, including climate change, urbanization, agricultural and industrial activities. Human activities cause the displacement of colonies from caves and other natural roosting areas into abandoned mines. Due to this, mines have become areas of interest for the conservation of cave-dwelling bats worldwide. The well documented persistent properties of metals in all environmental compartments (both biotic and abiotic), might compromise the biota living in mines even after operations have ceased. Thus, the aim of this study is to understand if cave-dwelling bats roosting in abandoned mines are being expose to metals. Non-invasive samples of fur, wing, and guano, of 140 individuals of four species of insectivorous cave-dwelling bats (R. ferrumequinum, R. euryale, R. hipposideros, and M. schreibersii) were collected on four abandoned metal mines in the north and center of Portugal, used as hibernation roosting sites for the species. Samples of soil, rock, and water were also collected from each mine to understand the origin of the exposure. The samples were evaluated in terms of the concentration of 13 essential and non-essential metals (As, Ag, Cd, Co, Cr, Cu, Mn, Ni, Pb, Se, Zn, Sn and W) using ICP-MS spectrophotometer. Metal concentrations were found in the four bat species in both wing and fur, confirming their exposure to the metals, with general higher concentrations found in wing membrane. Differences were found between M. schreibersii and the other bat species studied, with this species presenting the biggest metal concentrations. The differences between species might be explained by differences in foraging behavior and habitat use, linked to anthropogenic activities and metal content found in the environmental compartments. However, was not possible to identify clearly the routes of exposures present. In comparison with other studies, the concentrations found in cave-dwelling bats were higher than in bat species that have other behaviors and preference in terms of roosting sites. The results reinforce the importance of monitoring metals in species roosting in mines, since exposure to metals might constitute a potential risk for cave-dwelling bats.
Outro - O projecto de mestrado foi financiado pela Comissão Europeia através do programa Erasmus Mundus, referente ao curso "Mestrado Internacional de Ecologia Aplicada" (EMMC‐IMAE) (FPA 2023‐0224 / 532524-1-FR-2012-1-ERA MUNDUS-EMMC).

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Milne, Damian John. "Habitat relationships, activity patterns and feeding ecology of insectivorous bats of the Top End of Australia". Thesis, 2006. https://researchonline.jcu.edu.au/2019/1/01front.pdf.

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The wet-dry tropics of the Northern Territory (the Top End) has a diverse microbat fauna. It supports 28 of Australia’s 65 species, including one endemic species (Taphozous kapalgensis), both of Australia’s monotypic genera (Rhinonicteris and Macroderma) and two species considered to be rare or endangered (Saccolaimus saccolaimus and Hipposideros diadema). However, most aspects of the ecology of this fauna are poorly known. The aim of this study was to investigate the composition of microbat assemblages; describe the habitat relationships of the microbat fauna at both the community and species levels; assess microbat activity patterns at several temporal scales; and to conduct a dietary analysis of the microbats of the Top End. Robust methods for sampling bats are still being developed and tested. Based on recordings derived from the Anabat II detector, I compared the results of surveys where I changed the orientation of the detector, the type of recording media, and static versus active hand-held recording. Detector orientation did not significantly affect any survey results, more call passes were identified from digital recordings and more species were detected using hand-held recordings. I also derived species-accumulation curves for the Top End microbats and provide guidelines for minimum sampling effort in future studies. Patterns in the composition of assemblages of microbat species sampled during the late dry season (the ‘build-up’) in the Top End were assessed against a range of environmental factors as well as four a priori defined habitat types (riparian, escarpments, coastal and woodlands). In general, species assemblages were not clearly defined and the number of significant environmental associations was relatively few. The most distinct species assemblages were strongly associated with topographic and climatic variables. There were also limited associations with vegetation structure, fire and local roost potential but no associations with insects or water availability. Total species diversity at sample sites was associated with distance to rivers and rainfall. Generalised linear modelling (GLM) was used to develop habitat models for 25 of the 28 microbat species of the Top End. Based on these models, a geographic information system (GIS) was used to derive probability of occurrence maps for each species. Almost all of the models identified a unique combination of environmental variables, and the resulting probability of occurrence maps revealed a variety of patterns of predicted distribution. Annual rainfall and habitat complexity were identified as significant variables in the majority of the models. All of the spatial models were combined to derive a probability map of species richness of microchiropteran bats in the Top End. This map shows greatest species richness in the north-west and north-central parts of the study area. Temporal patterns of microbat activity and species richness were assessed at four scales: hourly, nightly, monthly and yearly, in relation to biotic (insect availability) and abiotic features in the environment. At the hourly scale, bat activity was highest in the first hour after dusk and declined throughout the night. Hourly bat activity was most closely associated with temperature. At the nightly scale there were significant associations between bat activity, moon light and temperature as well as a complex association with both moon phase and time of night. At the monthly scale bat activity increased dramatically in October which was possibly triggered by a combination of changing climatic factors that occur at this time of year in the Top End. At the yearly scale there was no overall difference in bat activity between years (n = 4) and no associations with climatic variables. The dietary composition for 23 of the 28 Top End microbat species was described by identifying the prey remains collected from stomachs and faecal pellets to the lowest possible taxonomic level (usually order or lower). Dietary analysis revealed that most species consumed a variety of orders indicating that Top End microbats have generalist dietary requirements and/or opportunistic foraging habits. However, the dietary compositions for H. diadema, H. stenotis, Mormopterus loriae, Nyctophilus geoffroyi, N. bifax and T. kapalgensis contained only one or two insect orders suggesting these species may have more specialised diets. Microbats in the ‘Uncluttered’ foraging guild consumed proportionally more insects belonging to the orders Orthoptera and Coleoptera whereas the ‘Background clutter’ and ‘Highly cluttered’ foraging guilds consumed proportionally more Lepidoptera. This study has greatly increased our understanding of some aspects of the ecology of microbats in the Australian wet-dry tropics. I make a number of recommendations for the conservation management and future research of Top End microbat fauna, most notably to investigate the association between microbat diversity and riparian areas, conduct further microbat surveys throughout the region to redress the still meagre number of records, and initiate targeted monitoring programs for microbats.

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Lin, Yu-Shyang, i 林渝翔. "Survey of Cryptosporidium oocysts in insectivorous bats in Taiwan and the influence of compost heaps treatment on Cryptosporidium oocysts". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/62804515977886088606.

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碩士
國立中興大學
獸醫學系
91
Cryptosporidium spp., the zoonotic infective parasitic protozoa in the digestive dust of vertebrates, is responsible for the clinical symptom of diarrhea. This study aims at a series of examination of parasites in insectivorous bats and Cryptosporidium oocysts were examined in the fecal samples from 24 bat habitats. After long observation of daily feces of the wild caged bats, discovered the existence of Cryptosporidium spp, which indicates these bats were infected. During the survey, the oocysts of Cryptosporidium spp observeed in the feces of 3 deer farms near a nocturnal bat habitat in Taichung county were presented positive for Cryptosporidium infection. The sample from a traditional compost heap in the deer farm was also examined as positive. Compared with the result of those from 12 modem compost heaps, the temperature of traditional compost heap is too low to destroy the Cryptosporidium oocysts. To survey for infection of deer by Cryptosporidium, the feces of deer from 17 daily farms was examined in central Taiwan. Among the 76 deer examined, 66 (86.8%) are observed to be positive for Cryptosporidium infection respectly. The cause may be mixture of fodder with feces. Since the feces of farm animals in central Taiwan have been stocked confidentially, those compost heap containing cryptosporidium oocysts may be carried by the wild filth flies, dung beetles and other insects which will be eaten by insectivorous animals and digested. Therefore, Cryptosporidium oocysts may in this way spread infection.

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Maas, Bea. "Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield". Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0022-5E77-5.

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