M.Sc. (Biodiversity and Conservation) / The relative activity levels of the Egyptian free-tailed bat (Tadarida aegyptiaca) and Cape serotine bat (Neoromicia capensis) were monitored in eight study areas spanning across the Eastern Cape, Western Cape and Northern Cape of South Africa. The detected activity levels were then used to study the habitat use and temporal distribution (across the night and months of monitoring period) of both species. The effect of weather conditions (namely temperature, relative humidity, wind speed, precipitation and barometric pressure), moon phase and moonlight on activity was also examined. The understanding of these aspects of the ecology of N. capensis and T. aegyptiaca were then used as guidelines to conserve these species with regards to wind farm development in South Africa. Bat activity was monitored by means of a total of seventeen passive monitoring systems consisting of SM2BAT+ bat detectors. The monitoring systems were deployed on the study areas to detect and record bat echolocation calls on a continuous basis throughout the night. Activity was recorded for a variable length of time, between 3 and 12 months, for each study area. The bat detectors were powered by solar energy systems. Habitat use by these species was analysed by comparing the activity amongst the different study areas. Both species showed considerable activity in most study areas depicting them to mostly be generalists inhabiting many habitats across the country. Bat activity amongst the different land use types, vegetation types and climate regions was studied. N. capensis showed significantly higher activity in a fruit farming area and T. aegyptiaca was significantly less abundant in dry and arid conditions than cooler humid environments. The preference for habitat based on altitude and height above the ground was assessed. The highest activity occurred in coastal regions of 0 – 500 m altitude. N. capensis was found to prefer activity at canopy height, and T. aegyptiaca is more of an opportunistic species making use of the most profitable vertical airspace at any one time Analysis of the hourly and monthly distribution of bat activity showed that it can be highly variable across a range of temporal scales from all study areas. On a broad scale, N. capensis was found to limit nightly activity within the first four hours of sunset, mostly peaking within the second hour. T. aegyptiaca tends towards peak activity within the first three hours of the evening, thereafter sustaining more or less constant activity until the ninth hour after sunset. For both N. capensis and T. aegyptiaca, activity in the Eastern Cape is greater over the months of September to March. Western Cape activity shows a general increase into the warm months of September – December followed by a decrease over the hot months of January and February. From the limited data set, activity in the Northern Cape seems to be highest over the months of November, December and April...

As human population grows and develops, more urban areas are expanding. Urbanisation has many impacts on the natural environment and one understudied pollutant is artificial light at night. The aims of this thesis were to examine the impacts of street lighting on bats and investigate the exposure of British bat species to artificial light at night and explored the mitigation option of part-night lighting. The current exposure of British bat species to artificial lighting was assessed using roost locations and population sizes from a long-term dataset (1997-2012) from the Bat Conservation Trust’s National Bat Monitoring Programme on seven bat species (Eptesicus serotinus, Myotis nattereri, Pipistrellus pipistrellus, P. pygmaeus, Plecotus auritus, Rhinolophus hipposideros and R. ferrumequinum). These data were combined with satellite imagery in roost sustenance zones and home ranges. Bat roosts were found in areas with brighter light levels than random locations for P. pipistrellus, P. pygmaeus and Plecotus auritus. Species that forage around streetlights (P. pipistrellus and P. pygmaeus) had significantly higher light levels in the landscape around their roosts than species which avoid street lit areas (R. hipposideros, M. nattereri and P. auritus). Colony size was negatively correlated with light levels. This study highlights that different species have different requirements in the landscapes around their roosts. To investigate landscapes effects of artificial light at night on the understudied light avoiding species R. ferrumequinum, eight maternity roosts were surveyed to explore the interaction between habitat features and street lighting. At each maternity roost, bat detectors were deployed at 25 paired street lit and dark locations. Street lighting had a significant negative effect on bat activity. Locations closest to the maternity roost had higher bat activity than those further away and road type had a significant effect on bat activity, with the highest bat activity recorded at minor roads compared with A and B roads. These results highlight the large negative impact street lighting can have on bat activity patterns and the need for mitigation. Several mitigation strategies have been suggested to combat the effects of artificial light at night but few have been tested. One of these suggestions is to restrict the hours of lighting through the night, often called part-night lighting. Part-night lighting has been implemented by many local authorities, often switching the lights off after midnight and switching them back on before dusk. To explore the effects of part night lighting on bats, the hourly patterns of activity for R. ferrumequinum were studied. Bat activity was bimodal, with a peak in the first few hours after sunset followed by a smaller peak before sunrise. To capture more than 50% of bat activity during the dark period of the night, street lights would be required to switch off before 11pm. To explore this further, a before-and-after study of part-night lighting was conducted at towns across Devon. Following the conversion from full-night lighting to part-night lighting, switching street lights off at 2 am, there was a significant reduction in P. pipistrellus and a significant increase for P. pygmaeus and Nyctalus noctule activity. Although part-night lighting is not often operational during peak activity periods for bat species, reducing the duration of lighting at night has impacts on activity patterns for several species. This thesis shows that artificial light at night has impacts on bats across the landscapes around their roosts. Artificial lighting has impacts for species in different ways, depending on whether they forage around street lights or avoid street lit areas. For species that avoid street lit areas such as R. ferrumequinum, street lighting can have very significant negative impacts on the availability of areas around their roosts. This highlights the need for conservation measures to reduce impacts of artificial lighting. Although mitigation schemes such as part-night lighting may help to minimize impacts of nighttime lighting, more tailored schemes for bats should devised to achieve greater conservation impacts.