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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Reproductive biology of the Egyptian free-tailed bat, Tadarida Aegyptiaca

Tsita, Johannes Ngoako January 1994 (has links)
The reproductive biology of Tadarida aegyptiaca was studied using specimens collected in the Cape Province of South Africa. The morphology of the reproductive tract of the species was generally similar to that of other molossids, however, the absence of Cowpers glands was unusual. Spermatogenesis began in February and spermatozoa were released to the cauda epididymis during August and September. Follicular development started in March and culminated with the appearance of Graafian follicles in July. Ovulation probably occurred in August and specimens were pregnant by September. Gestation length was estimated to be four to five months and a single young was born in December. The data suggest that T. aegyptiaca is monotocous and monoestrous.
2

The habitat use, temporal distribution and preferred weather conditions of Tadarida aegyptiaca and Neoromicia capensis, and its application to wind farm development in South Africa

Moir, Monika Ilka 08 October 2014 (has links)
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...

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