The maintenance and restoration of tropical forest biodiversity is a global priority. Madagascar, a biodiversity 'hots pot', is unique, yet highly threatened due to ongoing deforestation. In this thesis I focus on the Madagascar flying fox (Pteropus rufus), the largest Malagasy fruit bat, and its role in forest regeneration and maintenance. I use ecological niche modelling to indicate the most suitable roosting habitat for the species and predict changes in distribution based on future climate change scenarios. Future predictions suggested that by 2080 there will be significant shifts in the distribution of P. rufus towards the central, more upland part of the island. To evaluate the role of these bats in forest regeneration, I compare germination rates of bat-processed and unprocessed seeds. Furthermore, I conduct high-resolution Global Positioning System (GPS) tracking of P. rufus to document their home ranges, movement, foraging patterns and habitat preferences. The results indicate that passage through the gut of bats increased the germination rate of defecated fig seeds and bats were able to disperse seeds over large areas and into areas cleared of trees. The bats were recorded to fly up to 66.5 km per night at a maximum speed of 17.04 m/s and the home range of all of the 15 tagged bats was over 58,000 ha. Additionally, the bats preferred feeding in forest remnants hence increasing the chances of seed deposition in such habitats, and ultimately their regeneration. Pteropus rufus bats have short gut retention times (GRTs) (estimated at 12 min) but are sometimes able to retain seeds for over 20 h. Through feeding observations in the wild, captive feeding trials and GPS tracking, seed shadow maps were created. The maps indicated that bats produced extensive seed shadow webs when feeding on figs within their large forging areas. Although P. rufus plays an important role in the early succession of tropical forest in Madagascar, it is threatened by hunting and by roost disturbance. This study provides new insights into the ecology and behaviour of the Madagascar flying fox.

This thesis describes the numerical modelling of bioacoustic structures, the focus being the outer ear or pinnae of the Rufous Horseshoe bat (Rhinolophus rouxii). There have been several novel developments derived from this work including: • A method of calculating directionality based on the sphere with a distribution of measuring points such that each lies in an equal area segment. • Performance estimation of the pinna by considering the directionality of an equivalent radiating aperture. • A simple synthetic geometry that appears to give similar performance to a bat pinna. The outcome of applying the methods have yielded results that agree with measurements, indeed, this work is the first time TLM has been applied to a structure of this kind. It paves the way towards a greater understanding of bioacoustics and ultimately towards generating synthetic structures that can perform as well as those found in the natural world.

No description available.

Rivers and their associated floodplains are natural wildlife corridors used by a wide range of animal species. Most British rivers in both rural and urban areas have been significantly affected as a result of drainage, flood defence structures, urban development and direct habitat loss. This has, in some cases, fragmented the river corridor and affected the structure and function of the riparian zone. As landscape-scale conservation schemes aim to restore the ecology of rivers, I consider what affect the quality of the riparian zone (an area where the river channel, bank and flood plain interact) has on the foraging and activity of important riparian users, British bats, and assess their relevance as bioindicators of ecosystem health. A matched pairs design was used to test the effect of 'undisturbed' (high quality) and 'disturbed' (lower quality) riparian zones based on riparian width, habitat complexity, connectivity, and surrounding land use, on bat activity. In general, wider and more complex riparian zones did not show sign ificantly more bat activity overall, though exhibited significantly greater foraging activity expressed by the number of feeding buzzes recorded. However, species-specific responses showed that Pipistrellus pygmaeus and Myotis spp. (probably mainly Myotis daubentonil) were influenced by the quality of the riparian zone more so than known habitat generalists, such as P. pipistrellus. Small differences in the complexity and width of the riparian zone positively affected the foraging and activity of P. pygmaeus, whereas the presence of wider stands of wet woodland positively affected the foraging and activity of Myotis spp. Broader landscape features and the availability of insect prey also affected the activity of two sympatric species, P. pipistrellus and P. pygmaeus. Both species were positively associated with the presence of urban habitat within a 2 km radius of survey sites and aquatic invertebrates, and showed niche differences related to known dietary preferences. The association with invertebrate abundance may make Pipistrellus bats potential bioindicators of riverine health. Pipistrellus bats select riverine habitats that are associated with urban areas, which may indicate a dependency on rivers in urbanised areas. The composition of the riparian zone and floodplain habitat affects the foraging and activity of riparian specialist British bats and should be considered when designing landscape-scale conservation schemes that include British rivers.

The presence of bats inside church buildings can result in negative impacts, requests for advice and disagreements about what management approaches are appropriate. Despite the suspected importance of churches for bats, there has been little research focusing on the ecology and behaviour of bats in church buildings, and current gaps in knowledge sometimes restricts the quality of advice that can be given. This study makes use of several approaches (examination of existing records, a regional field survey, temperature and acoustic monitoring and radio-tracking) to improve understanding of the ecology of bats roosting in churches, with a focus on Pipistrellus pygmaeus (which can cause some of the most severe problems) in eastern England. The study focused on this region because it had the highest number of requests for advice about bats from church representatives in England. Inside churches, roof or ceiling crevices in the south sides of churches were preferentially selected as roost sites, and were also warmer than equivalent crevices in the north sides of churches. Roost crevices were characterised by fluctuating temperatures which warmed dramatically during the day and cooled at night, whereas church interior temperatures were stable. Within the highly modified, fragmented arable landscapes of eastern England, a modelling approach showed that P. pygmaeus selects church roosts with more wetland habitat cover within typical commuting distance, and which are closer to broad-leaved woodland, than churches in general. Radio-tagged female P. pygmaeus typically select wetland and woodland habitats for foraging, with arable land consistently the least selected, but most available habitat. I found substantial differences among colonies in home range and commuting distances, with bats from one colony commuting up to 15.9 km to reach foraging resources. Mobility may be important for the persistence of P. pygmaeus in fragmented landscapes by allowing bats to exploit multiple distant and dispersed foraging patches. Radio-tracked P. pygmaeus bats from three colonies collectively made use of multiple alternative day roosts in a range of structures across large areas, but bats at two colonies mostly day roosted in their respective church roosts. Using automatic, continuous acoustic monitoring, I found that P. pygmaeus bats were present and active inside three medieval churches throughout the year, with activity peaking in July. P. pygmaeus activity inside churches was positively correlated with night-time temperatures and negatively correlated with wind speed. Recommendations for conservation management are made along with possible future directions for applied research.

The evolutionary history of echolocation in bats is poorly understood, as fossils provide little direct evidence, and most studies into echolocation have taken an ecological approach. Bats use a wide variety of echolocation call structures despite facing similar sensory challenges, and it is not clear how and why these echolocation call types evolved, or what impact they have on other aspects of the evolution of bats. Here, I use phylogenetic comparative methods and newly-collated echolocation call data from 410 species in 120 genera and all 19 families to investigate the origination and evolution of echolocation in bats (Chiroptera). I construct an updated phylogenetic supertree of the bats using source phylogenies from the literature between 1970 and 2009. I ask three main questions: (1) Are echolocation call structures really a product of present-day ecological conditions, or are they much more constrained by evolutionary history than is currently thought? (2) What did the first echolocation calls sound like? (3) Are echolocation calls ‘key innovations’ that promote diversification? I found that early divergences and subsequent constraints in evolutionary history have resulted in a greater variety of bat call structures than appear to be functionally necessary. The structure of the first echolocation calls was predicted to be short duration, multi-harmonic, and narrowband, suggesting that the proto-bat was a slow and manoeuvrable flier with an opportunistic and omnivorous diet, and may have used a perch-hunting foraging strategy. Finally, some echolocation call types were found to correlate with higher diversification rates such that they may be considered key innovations, but, unexpectedly, the most rapidly diversifying clades were those in which species either did not use echolocation at all (Pteropodidae), or where less sensory reliance was placed on echolocation (Stenodermatinae: Phyllostomidae).

Hibernation occurs in a diverse range of animal species including amphibians, reptiles, insects, mammals and birds. The adaptations that hibernators have evolved to survive winter are of great interest to conservation ecologists. The discovery that hibernators frequently arouse during winter has instigated much research on physiology and behaviour. Hibernation also provides an opportunity to better understand biological rhythms and entrainment to environmental cues. Using an integrative biological approach this study explores some questions important for a better understanding of mammalian hibernation. My aim was to gain insight into how hibernators use torpor during winter in a location with a mild maritime climate and to better understand some of the behavioural adaptations that have evolved to exploit opportunities that arise during winter. The primary study site was Greywell Tunnel, a disused canal tunnel situated on the Basingstoke Canal in Hampshire, England. The tunnel is an important hibernation site for Natterer's bat Myotis nattereri, four other bat species have also been recorded. The bat population using Greywell Tunnel has been monitored since the tunnel's designation as a Site of Special Scientific Interest in 1985. Long-term surveillance of bats at hibernation sites is a useful technique for assessing population trends. Findings from winter surveillance surveys conducted at Greywell Tunnel showed that numbers of M nattereri counted appeared to dip then rise over the survey period, while numbers of M daubentonii, M mystacinus and M brandtii appear to have declined significantly at this site. In locations where winter foraging opportunities exist, two strategies (which may not be mutually exclusive) may enable bats to balance winter survival with the ability to exploit foraging or possible mating opportunities.

No description available.

Acoustic bat detectors are an extraordinarily valuable tool in bat research as they enable researchers to listen in on the otherwise secretive world of bats, providing the means to nqn-invasively survey and monitor bats in their natural habitats. Technological advances facilitate unprecedented data collection, considerably expanding the scope of field studies. However, the burden of manual analysis, and difficulty in identifying some species reliably from their calls, hampers the development of systematic survey and long- term monitoring methods. We developed a series of algorithms for the automated analysis of bat detector recordings, used to detect and extract calls from continuous recordings, and measure temporal and spectral call variables. By hand-labelling the .location of calls in field recordings, we were able to evaluate the accuracy of the automated method at detecting calls. Comparison on the same dataset with two conventional bioacoustic signal detectors revealed our algorithm was more accurate and robust. Using machine learning (ML) classification algorithms that learn to identify calls following training using a reference library, we developed a fully automated species identification system. Evaluation of the system was carried out by cross-validation of our reference call library, containing recordings of >5000 calls from known British species, comparing classifier predictions to ground- truth labels. The ML approach outperformed conventional statistical analysis using discriminant function analysis (DFA). We applied our novel system to two field studies that highlight its utility. Firstly, monitoring multi- species bat activity at a remote cave system over a period of three months, analysing >20,000 audio files to investigate temporal patterns in activity. Secondly, separating acoustically cryptic Myotis species from data collected in the Lake District National Park, to generate presence data for species distribution modelling, facilitatinq the creation of species-specific habitat suitability maps projected over the entire Park (ea, 3,300 km").

Bats are vital to Great British biodiversity; they are the primary consumers of nocturnal insects, disperse nutrients across landscapes, and are excellent bioindicators of an ecosystem’s health. The diversity of bat species in the UK is thought to be as a result of extensive resource partitioning. There are numerous methods used for studying bat diets, each with benefits and drawbacks. Past research has compared small numbers of species at a time, making inter-species comparisons difficult. Our large repository of bat guano samples, collected from around the UK, has allowed us to study the bat species under one methodological ‘umbrella’. This thesis is divided into 7 chapters. This first chapter gives a broad overview of the project, framing this research and provides an overview of the technologies available, and how their development has enabled environmental research on a scale, which, until recently, would have been unimaginable. The second chapter is a meta-analysis of the literature that pertains to bat diets. These data will be used to inform the design of primers in the barcoding stages of the project. Next is a shotgun metagenomic analysis of a selection of guano samples from across the range of the UK species. This method provides information, not only about diet species, but also about the bat, viral, and bacterial DNA. Analyses of this data show that there are several dietary forms seen between the species. The fourth chapter is a targeted amplicons metagenome study of the mitochondrial COI barcode region from the arthropod species identified in the literature review, and from metagenomic data-set. This provides a greater resolution picture of the diet species present. Analyses of these data use phylogenetic intersection analysis to ensure the robustness of the taxonomic assignments in the face of the patchy databases available. In the fifth chapter, I draw together the data gathered using the different approaches and presented in the previous chapters. I discuss the efficacy of the methods, and assess the role of resource partitioning in bat species co-existence. The sixth section will look at the appropriateness of using guano morphology as a diagnostic of species presence. Finally, in chapter seven, I summarise these data in the wider context of bat ecology, comment on the implications of the research for conservation, and discuss potential directions for the field in the light of this research.