Ric T. F. Bernard

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Patterns of reproduction in African bats can be compared in three taxon-based groups: fruit bats (Megachiroptera), freetailed bats (Microchiroptera: Molossidae) and the nonmolossid Microchiroptera. In the fruit bats and nonmolossid Microchiroptera there is a trend from either seasonal or aseasonal polyestry, with prolonged or continuous spermatogenesis in(More)
The Soricidae are generally considered to comprise two subfamilies--Crocidurinae and Soricinae--each of which has distinctive reproductive characteristics. Although Myosorex varius is classified as a crocidurine, the features of its reproductive system call that classification into question. Compared with three other shrew genera, Myosorex exhibited a(More)
In Schreibers' long-fingered bat from South Africa (approximately 33 degrees S) copulation, ovulation and fertilization occurred in April and May, implantation was delayed until August, and parturition occurred in December. Delayed implantation coincided with winter, during which the bats remained active, only entering prolonged periods of torpor during(More)
Spermatogenesis in Schreibers' long-fingered bat from approximately 33 degrees S in South Africa was seasonal, and occurred in the 3 months (February-April) preceding ovulation. The ultrastructure of the Leydig cells indicated a period of increased steroidogenesis at this time, and plasma testosterone concentrations were elevated from March to May (10.3(More)
Little is known about the role of photoperiod in the control of reproduction in mammals from the tropics in general and, in particular, from the Afrotropics. The present study examined the reproductive photosensitivity of the pouched mouse (Saccostomus campestris: Cricetidae), a small, seasonally breeding rodent that occurs from about 12 degrees S to 33(More)
The effects of physiological concentrations of melatonin on motility of spermatozoa from Wistar rats were assessed in vitro. Melatonin had dose-dependent negative effects on sperm forward progression, the quality of sperm motility and on a sperm motility index. Some, but not all of these effects were due to ethanol (0.5% final concentration) which was used(More)
We used published results from studies in Africa to test the hypothesis that the timing of parturition in the Chiroptera is constrained by rainfall. Comparison of year-round rainfall and insect data at various latitudes showed that insect abundance peaks approximately a month after peak rainfall. A similar comparison of parturition time to rainfall showed(More)
Thermal preference in a temperature gradient was investigated in Schreibers' long-fingered (Miniopterus schreibersii) and Cape horseshoe (Rhinolophus capensis) bats in relation to their roost temperatures. Both species selected a wide range of temperatures but R. capensis selected a narrower range and most frequently selected temperatures were 2-3 degrees C(More)
Reintroductions of large carnivores into enclosed reserves that confine movements may fail due to intensive intra-guild interspecific conflict. To assess conflict potential, in winter 2006 we used direct observations aided by radio-tracking to focally monitor continuously one female cheetah with cub (Acinonyx jubatus), a female leopard (Panthera pardus),(More)
This study was an examination of the effect of photoperiod on spermatogenesis and the accessory glands of the four-striped field mouse (Rhabdomys pumilio), a seasonally breeding rodent that occurs through Southern Africa. Adult scrotal males were exposed to either short day length (10L:14D), long day length (14L:10D), or natural photoperiod in(More)