Thesis (Ph. D.)--University of Hawaii at Manoa, 1993. / Includes bibliographical references (leaves 126-136) / Microfiche. / xi, 136 leaves, bound ill. (some col.) 29 cm

Thesis (Ph.D.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 81-86)

Thesis (M.S.)--Villanova University, 2006. / Biology Dept. Includes bibliographical references.

No description available.

Bats are one of the most numerous and diverse orders of mammals. This diversity is reflected in the wide range of bat morphologies. The relationship between bat foraging behaviours, flight styles and wing shapes has been well studied. Little research, however, has focused on other features of bat morphology, such as ear and tail membrane size, and how variations in these affect a bat’s locomotion. Indeed, knowledge on this topic has at best been speculative. In this thesis, I provide insight into the trade-offs and relationships that exist between less studied aspects of bat morphology, and their foraging and locomotion, with focus on the group of bats referred to as gleaners. In this thesis I use a model bat in wind tunnel tests to demonstrate that the long ears of some bat species have profound implications for their aerodynamic performance, and their energetics. A trade-off, however, is likely to exist, since the long ears provide a foraging benefit, which may balance the additional flight cost of the large ears. Additionally, bats may be able to minimise the flight cost of their ears through appropriate ear positioning. Using data collected from museum specimens I also demonstrate that other features of bat morphology, particularly the tail membrane, are good indicators of foraging strategy. Gleaning bats are identified as the group with the largest ears, whilst commuting bats have the shortest tail membranes. The energetic implications of these variations in morphology were then investigated using a theoretical model. The theoretical model suggested that tail morphology, as well as ear morphology, was likely to have a profound effect on flight performance in bats In contrast to bird tails the aerodynamic function of bat tail membranes is not well understood. Accordingly, I investigated bat tail membrane aerodynamics empirically using a model suspended in a wind-tunnel and from this was able to present the first evidence that bat tail membranes fulfil an important flight control function. Although bats primarily fly, certain species, such as the gleaning bats, spend a significant proportion of their foraging time on or near the ground and vegetation, landing to capture prey. Several gleaning species are also documented as frequently jumping from the ground back into flight. Research, however, on bat jumping had previously concentrated on the unusual vampire bats. I, therefore, present further data on bat jump performance and show that no ecological trend is present, with body mass being the best indicator of performance. No correlation between foraging habit and take-off performance suggested that flight so dominates bat morphology and locomotor performance that other modes of locomotion tend to be derivative. The findings of the thesis presented here, provide important insights into the relationships that exist between gleaning bat morphology, locomotor performance and foraging strategy. Areas for future research are also identified.

Sonar is an important sensory modality for engineers as well as in nature. In engineering, sonar is the dominating modality for underwater sensing. In biology, it is likely to have been a central factor behind the unprecedented evolutionary success of bats, a highly diverse group that accounts for over 20% of all mammal species. However, it remains unclear to what extent engineered and biosonar follow similar design and operational principles. In the current work, the key sonar design characteristic of beamwidth is examined in technical and biosonar. To this end, beamwidth data has been obtained for 23 engineered sonar systems and from numerical beampattern predictions for 151 emission and reception elements (noseleaves and pinnae) from bat biosonar. Beamwidth data from these sources is compared to the beamwidth of a planar ellipsoidal transducer as a reference. The results show that engineered and biological both obey the basic physical limit on beamwidth as a function of the ratio of aperture size and wavelength. However, beyond that, the beamwidth data revealed very different behaviors between the engineered and the biological sonar systems. Whereas the beamwidths of the technical sonar systems were very close to the planar transducer limit, the biological samples showed a very wide scatter away from this limit. This scatter was as large – if not wider – than what was seen in a small reference data set obtained with random aluminum cones. A possible interpretation of these differences in the variability could be that whereas sonar engineers try to minimize beamwidth subject to constraints on device size, the evolutionary optimization of bat biosonar beampatterns has been directed at other factors that have left beamwidth as a byproduct. Alternatively, the biosonar systems may require beamwidth values that are larger than the physical limit and differ between species and their sensory ecological niches. / Master of Science

The long-term effects of large-scale changes in forestry, agriculture and other land use on habitats and the large-scale expansion of wind farming  affects bats foraging environments. In order to predict consequences of exploitations on local bat species and populations, good surveys are important. To get good background information for an Environmental Impact Assessment (EIA) it  is crucial to rapidly assess which areas are most important for bats. The aim of this work was to measure the importance of the two types of forest environment for bats foraging : forest areas located close to or far from the lakes. Bat activity and species diversity was measured with automatic ultrasound recorders in 211  nights of fieldwork at 155 locations in 23 areas in different parts of Sweden during June, July and the first two weeks of August 2011 and 2012. A total of 11 species were recorded in forest far from lakes and 8 species in forest close to lakes. Eptesicus nilssonii , Myotis sp. and Pipistrellus pygmaeus were the most common taxa in both habitat types. Activity levels were higher in the vicinity of lakes compared to forests far away from lakes. Species diversity calculated on base on Chao 2 was similar for both types of habitats . The results suggest that the forests close to lakes are the most important habitats to surveys for bats in Sweden and that inventory efforts should be primarily invested in them.

Good estimations of habitat preference and activity of bats in different habitats are of great importance when planning for conservation or assessing consequences of exploitation. The objective of this study was to compare two different methods for abundance estimation: line- transects (active taxation) and point taxation by autobox recordings (passive taxation), and correlation analyses were made between data from these methods. The species used was Eptesicus nilssonii, which is easy to identify and one of the most common bat species in Sweden. Differences in abundance between edge zones and non-edge zones were tested. The equations from the correlations would allow the use of passive taxation data for abundance estimates. Using the equations produced in the correlation analysis, and data collected in other projects at different sites in southern and central Sweden, an estimation of the total number of E. nilssonii in southern and central Sweden was made. This data was also used in order to test differences in abundance between habitats close to and further away from water. However, no differences in abundance between different habitats could be seen. Significant correlations were found between active and passive taxation data. The total number of E. nilssonii individuals in southern and central Sweden was estimated in two different ways: 1. by using the total number of passive taxation observations, to about 5 million individuals and, 2. by using the number of five minute period containing at least one observation, to 4 million individuals. How to increase the precision of these figures are discussed.

Thesis (M.S.)--Missouri State University, 2009. / "May 2009." Includes bibliographical references (leaves 41-47). Also available online.

The objective of this research is to analyze the relationship between environ-mental heat exchange and vascular response in the pallid bat wing during systemicheating and to develop a simplied model of heat transfer for theoretical analysis.During heating experiments, metabolic activity, body temperature and alterations invessel diameter and blood ow were monitored. This research is very signicant, asit will correlate thermoregulation and vascular response in a way that has not beenstudied before.The wing of the pallid bat is selected because the microvascular bed performssimilar functions as that of the human skin in terms of thermoregulation; understand-ing vascular response to heat or cold allows to analyze vascular function, or arterialhealth, a response that is altered at early stages of several diseases in humans. Athigh body temperatures, bats can dissipate heat through their wings; the bat wingserves as a thermal window where heat exchange is determined by local blood owand vascular response in the wing.For this study, a lumped mathematical model to calculate body and skin tem-perature alterations in response to changes in environmental conditions has beendeveloped. In order to formulate this model, experiments have been proposed wherethe pallid bat is subjected to dynamic systemic heating with and without the wingextended. By having the wing extended outside a metabolic chamber during heating,the bats were able to maintain an equilibrated body temperature; having the wing enclosed caused body temperature to increase rapidly. The experiments were designedto obtain correlations between systemic and vascular responses and therefore learnabout the thermoregulatory mechanisms of the pallid bat.Results from experiments following Animal Use Protocols 2006-253 and 2007-110indicate that vascular responses to environmental temperature changes (changes inTchamber) maintain or reduce body temperature to basal conditions. Vessel diameter,centerline velocity, blood ow and heat ux increase with Tchamber therefore deliveringa greater volume of blood to the bat wing and increasing heat exchange with theenvironment. The positive responses in the wing to Tchamber signify that the pallidbat is regulating its body temperature as had been expected.