published_or_final_version / abstract / Microbiology / Master / Master of Philosophy

Urbanisation is a key driver in the loss, fragmentation and modification of natural habitats resulting in the global loss of biodiversity. As the human population, and consequently the rate of urbanisation, continues to increase exponentially it is important to understand how to sustain and enhance biodiversity within the built environment. Cities comprise a complex assortment of habitat types yet relatively little is known of how its composition and spatial configuration can influence species presence or foraging activities. It is therefore necessary to examine habitat use and biodiversity patterns at multiple spatial scales to fully understand how species are responding to the urban matrix. There are few other orders of animals that are as strongly associated with people as bats (Chiroptera); for some bat species human habitations provide roosts and adaptations of the environment provide food sources. However bat species richness generally declines with increasing urbanisation indicating that many species are not able to persist in highly urbanised areas. In this thesis, I show that the behaviour, habitat preferences, and distribution of bats are strongly influenced by the built environment at both a local and landscape scale. Although many animal species are known to exhibit sex differences in habitat use, adaptability to the urban landscape is commonly examined at the species level without consideration of potential intraspecific differences. I found that female Pipistrellus pygmaeus show greater selectivity in foraging locations within urban woodland in comparison to males at both a local and landscape scale. There was a lower probability of finding females within woodlands which were poorly connected, highly cluttered, with a high edge: interior ratio and fewer mature trees. The results have important implications for our understanding of how to manage areas for breeding females and highlight the need to supplement acoustic monitoring with trapping data to assess sex differences in habitat use. Determining how morphological or behavioural traits can influence species adaptability to the built environment may enable us to improve the effectiveness of conservation efforts. The morphological similarities between P. pygmaeus and P. pipistrellus suggest that both species should respond similarly to the urban matrix, however I found differential habitat use occurring within a variety of urban habitats (e.g. woodland and waterways) and at a landscape scale. In urban woodland there was a higher probability of P. pygmaeus activity relative to P. pipistrellus in woodlands with low clutter and understory cover which were surrounded by low levels of built environment. Many bat species are strongly associated with aquatic or adjacent riparian habitats yet we know little about the utilisation of urban waterways by bats. After surveying urban waterways throughout the UK, I was able to show that the built environment can negatively affect a variety of bat species from the riparian zone up to 3km from a waterway. This indicates that beneficial urban waterway rehabilitation schemes for bats require management at multiple spatial scales, from retaining a vegetated riparian zone at the local scale to highlighting the necessity for conservation funding to be spent on the implementation of landscape scale environmental improvement schemes that encompass the entire urban matrix. Undertaking surveys to confirm species presence or to estimate population sizes can be difficult, particularly for elusive species such as bats. I was able to demonstrate a variety of ways to increase surveying efficiency (e.g. the use of an acoustic lure to increase bat-capture rate) and a significant relationship between bat activity and the relative abundance of certain species of bat which can maximise the knowledge of diversity in an area whilst minimising wildlife disturbances. Urbanisation has also had strong negative effects on many insect groups, such as moths, which are important components of the diets of many bat species. I found that woodland vegetation characteristics were more important than the surrounding landscapes in determining the abundance, species richness, and species diversity of moth assemblages within urban woodland. This indicates that management at a local scale to ensure provision of good quality habitat may be more beneficial for moth populations than improving habitat connectivity across the urban matrix. The findings presented in this thesis have important implications for our understanding of the adaptability of species to the built environment and for the management and monitoring of bat populations. It also highlights that even common bat species are negatively affected by urbanisation and much greater attention should be paid to securing their future within the urban landscape.

Includes copies of author's previously published works / Guano deposits in caves form a rich food resource supporting diverse arthropod communities. Guano piles consist of distinct micro - habitats, fresh, moist, highly basic guano and older, dry, slightly acidic guano. Micro - habitat variation is strongly controlled by seasonal guano deposition that, in turn, effects the structure of arthropod communities. The maternity chamber of Bat Cave, Naracoorte, South Australia, contains extensive guano deposits supporting 38 species from three classes and 12 orders. This community was studied to determine spatial and temporal variation of arthropod communities, and biogeographic relationships between different regions in Australia. Species richness forms a positive linear relationship with pH, in situ moisture content and guano deposition. Many species show strong associations with fresh guano and hence are strongly seasonal, although some species are present throughout the year. Arthropod community structure in winter was found to be more closely related to prior summer arthropod structure than to subsequent seasons. Starlight Cave near Warrnambool, western Victoria, the only other maternity site for Miniopterus schreibersii bassanii, contained 43 species from 39 families and 14 orders. Seven species are common to both caves. The community structure of Starlight Cave was found to be more homogeneous than Bat Cave with samples clustering by season rather than sample year as was the case at Bat Cave. Different cave morphology was found to significantly alter the micro - habitat conditions and, hence, community structure in Starlight Cave compared with Bat Cave. Migration of guano associated arthropods at local, regional and continental scales was assessed using mtDNA and allozyme electrophoresis the pseudoscorpion genus Protochelifer as a model organism. Phylogenetic tree reconstruction revealed a wide geographic distribution of cavernicolous species across southern Australia. Cave colonisation is believed to have occurred only once, followed by dispersal to the Nullarbor Plain and other caves in south - eastern Australia. Dispersal was possibly phoretic on cave bats or occurred prior to aridification of surface environments that currently restricts migration. The distribution of guano - associated arthropods from arid, semi - arid and monsoonal karst areas in Australia are compared with temperate south - eastern Australia. Different climatic areas show large biogeographical differences in community structure, although similar families ( Urodinychidae, Reduviidae, Anobiidae, Carabidae and Tineidae ) are present in many Australian guano communities. Several potential mechanisms of dispersal are discussed including phoresy, colonisation from soil, terrestrial migration and interstitial cavities. Endemism to specific caves cannot be definitely assigned to any species, although 13 species show restricted distribution. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2006.

Thesis (M.S.)--Marshall University, 2002. / Title from document title page. Document formatted into pages; contains vi, 50 p. with illustrations and maps. Includes bibliographical references (p. 22-26).

The synanthropic molossid bat, Mops leucostigma (Allen 1918), is widely distributed across Madagascar and has recently been described from the Comoros. M. leucostigma individuals from eastern Malagasy populations are markedly larger than those from the west, and Mops leucostigma populations from Madagascar are morphologically distinct from populations of its putative sister species, Mops condylurus from mainland Africa (Ratrimomanarivo et al. in press, Genetic diversity was assessed by sequencing the mitochondrial cytochrome b (n = 56) and displacement loop (D-loop) (n = 64) regions of Mops leucostigma individuals from a broad range of locations across Madagascar, and Mohéli and Anjouan in the Comoros. Specimens of Mops condylurus (n =3), Mops midas (n =3) and Otomops martiensseni (n = 1) were included in the study for comparative purposes as outgroups. Phenetic and cladistic analysis of cytochrome b and D-loop sequences strongly supported the reciprocally-monophyletic status of Mops condylurus and M. leucostigma. Comorian (Mohéli and Anjouan) and Malagasy M. leucostigma samples formed a monophyletic Mops leucostigma group, within which Comorian samples formed a poorly-supported subclade in the cytochrome b analysis only. Cytochrome b genetic distances of 13.8 % separated M. midas from M. condylurus and M. leucostigma, which formed reciprocally-monophyletic sister groups separated by genetic distances of 2.5 % for cytochrome b and 13 % for the D-loop. 49 M. leucostigma cytochrome b sequences yielded seven haplotypes, two of which were exclusive to the Comoros. D-loop haplotype analysis did not support the distinctiveness of the Comorian samples. Genetic distances within M. leucostigma samples were low (0.22 % for cytochrome b and 1.91 % for the D-loop). Comorian samples were found to be genetically attributable to M. leucostigma. Clear phylogenetic separation between M. condylurus and M. leucostigma was found in all analyses, consistent with their status as phylogenetic species within the genus Mops. There was no clear correlation between haplotype distribution and aspect (east/west-facing slopes), elevation or gender. Low mtDNA variation (cytochrome b and D-loop) and lack of phylogeographic concordance indicates that the observed morphometric variation between eastern and western Mops leucostigma populations may possibly be explained in terms of adaptation to local environmental conditions. / Thesis (M.Sc.)-Univeristy of KwaZulu-Natal, 2008.

Predicting species occurrence based upon landscape-scale characteristics is a fundamental goal of ecology and conservation biology. Accurately predicting the potential occurrence of a species is fundamental to management activities that involve large areas where sampling is difficult due to logistical or financial constraints. During the summers of 2001-2003 mist nets were used to capture bats in Whiskeytown National Recreation Area (WNRA), Lassen Volcanic National Park (LVNP), and Lassen National Forest (LNF) in northern California. I used logistic regression and Akaike's Information Criterion (AIQ to model species distributions. Models developed a priori were used to determine which variables best discriminated between capture sites and non-capture sites. Prediction models were mapped using Geographic Information Systems. In WNRA, for all bat species combined total edge was most parsimonious, whereas in LVNP elevation was best for all species. Elevation and tree size were important in predicting the occurrence of pallid bats (Antrozous pallidus), in LNF. Results of this study are important to wildlife managers within the study areas because the models can be used to minimize deleterious impacts on bats. Moreover, distribution maps are valuable to bat conservation efforts because they provide baseline data important for evaluating and predicting population responses to management activities. / Department of Biology

Thesis (M. Sc.)--York University, 2003. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 72-84). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ82961.

The increasing number of proposed wind farm developments in South Africa provides an immediate reason to assess bat activity and diversity, with the expectation of developing measures to mitigate for negative impacts. The overall aim of this thesis was contribute to an understanding of the drivers of bat activity, relevant to wind turbines, and to determine what factors (exogenous – environmental, or endogenous – intrinsic physiological processes) contributed to observed bat activity patterns, at the Metrowind Van Stadens Wind Farm in the Eastern Cape of South Africa. A combination of active (mist netting) and passive (acoustic) bat monitoring techniques were used to determine free-ranging bat activity patterns (Chapter 3). A total of 889 bat passes were recorded over 323 detector nights from the beginning of May 2012 to the end of December 2012. The Cape serotine bat (82 per cent) and the Egyptian free-tailed bat (97 per cent) made up the majority of all bat passes recorded on site. Large variations in bat activity per month and per hour were apparent, with bat activity peaking in May 2012 and during the first few hours after sunset (18:00-23:00). Patterns in nightly, free-ranging bat activity at the site were modelled against various environmental conditions. Month, temperature, wind speed and an interaction between month and rainfall were the most significant predictors of bat activity, explaining 80 per cent of the variation observed on free-ranging bat activity patterns. A total of eight Cape serotine bats (Table 4.1.) were caught in mist nets on site and changes in the resting metabolic rate (RMR) of torpid (n = 6), and normothermic (n = 2) bats, over a 24 hr period, were measured and used to predict free-ranging Cape serotine bat activity (Chapter 4). Cape serotine bats showed a high proclivity for torpor in the laboratory and peaks in RMR were observed at 18:00 (0.89 ± 0.95 VO2 mℓ.g-1.hr-1) and again from 20:00-21:00 (0.89 ± 0.91 VO2 mℓ.g-1.hr-1). Peaks in RMR of torpid individuals coincided with peaks in the average hourly free-ranging activity of the Cape serotine bat, and RMR explained 33 per cent of the variation and was a good predictor of free-ranging bat activity (R2 = 0.2914). This study showed that both exogenous (Chapter 3) and endogenous (Chapter 4) factors drive bat activity in the wild. Although this dissertation was not intended for wind turbine management, the information presented on the biology and activity of bats is important for managing interactions between bats and wind turbines. By determining what factors influence bat activity, we are able to predict when bats will be most active and thus can develop mitigation measures to reduce the potential impacts that wind turbines will have on the bat community. In order to conserve bats and reduce potential bat fatalities from occurring at the site, mitigation measures should be concentrated to those times when bats are most active (May and during the first few hours after sunset – 18:00 to 22:00).

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Many bat species in Europe have undergone severe population declines during the last century and one of the driving causes is believed to be the loss of roosting and foraging habitat through agricultural expansion and intensification. Modern agricultural practices have also had strong negative effects on many insect groups, such as moths, which are important components of the diets of many bat species. Agri-environment schemes (AES) have been introduced in many countries as an attempt to counteract the negative effects of intensive agriculture on biodiversity by providing financial incentives for farmers to adopt environmentally-sensitive agricultural practices. AES are potentially beneficial to bats and nocturnal insects, but the response of these taxa to their implementation had not been assessed prior to this study. Here, the potential benefits (or otherwise) that bats and their insect prey species gain from the implementation of certain AES management prescriptions was assessed using ultrasonic detectors (to assess bat activity levels) and heath light traps (to quantify nocturnal insect abundance) at 18 pairs of AES and conventionally-managed farms. In addition, the influence of the surrounding landscape on bats and insects was quantified to evaluate the relevance of a landscape-scale management approach for the conservation of these taxa. Some of the AES prescriptions assessed in this study benefited moths (and are potentially beneficial for moth-eating bats), but not Pipistrelle bats nor their insect prey. The most important factors associated with bat activity on farmland were metrics related to woodland configuration in the surrounding landscape, which suggests that conservation efforts for bats should focus on the creation and management of this habitat. Currently, some AES prescriptions aim to increase the amount and quality of woodland on agricultural land, but little is known about how woodland character relates to bat abundance and insect prey availability; therefore, recommendations for woodland creation and management rarely consider the requirements of foraging bats. Here, the influence of woodland character (e.g. vegetation structure and patch configuration) on bats and nocturnal insects was assessed. Vegetation surveys were conducted and Geographic Information Systems (GIS) were used to quantify the vegetation character and spatial configuration of 34 woodland patches within farmland. Two complementary methods (acoustic monitoring and bat trapping assisted by an acoustic lure) were used to assess the influence of woodland vegetation character, patch configuration and the surrounding landscape on bat populations. Nocturnal insect abundance at each site was assessed using heath light traps. Data presented here demonstrate that bats show species-specific associations with woodland vegetation structure and patch configuration; patterns of higher bat abundance and activity at small and isolated woodland patches suggest that bats utilize this habitat more intensively in landscapes where woodland is scarce. This thesis also shows that moths are strongly influenced by woodland character; in general, large woodland patches of compact shapes, composed of a large number of native tree species and a dense understory cover, and located close to other woodlands were associated with high moth abundance and species richness (and are potentially valuable for moth-eating bats). Other nocturnal insects (mainly Diptera) were not influenced by woodland character. This study also shows that bats and nocturnal insects are influenced by the landscape context; moths are mainly influenced by the extent of semi-natural environment (such as rough grassland and scrub) within small spatial scales (within 250 m; although effects of woodland extent were detected at larger spatial scales for woodland specialists moths). Bats are mainly influenced by woodland-related landscape metrics. Some bat species are influenced by the surrounding landscape at large spatial scales (within 3 km) and would benefit from woodland creation and management at a wide-landscape-scale. The findings presented in this thesis have important management implications for the design of agri-environment schemes. A list of management recommendations to optimize the benefits that bats and nocturnal insects gain from these schemes is presented in the final section.