Arid and semi-arid environments are characterized by extreme fluctuations in temperature and low rainfall, which present significant challenges to the animals inhabiting these areas. However, the presence of burrows may allow animals to avoid climatic extremes and predators and may act as valuable foraging sites. We assessed the microhabitat conditions (maximum and minimum temperature, relative humidity and seed abundance) of aardvark (Orycteropus afer) burrows in relation to paired non-burrow areas at three sites in South Africa. We also describe the extent to which they are used as resources by other vertebrates. Maximum temperatures were significantly lower and minimum temperatures and relative humidity values were significantly higher inside the burrows than outside. The concentration of seeds inside the burrows and at the paired non-burrow sites was similar. Twenty-seven vertebrate species (21 mammals, two birds, three reptiles and one amphibian) were recorded making use of the burrows and it is likely that these species accrue benefits (e.g. a buffered microclimate) from burrow use. However, our sampling was biased towards mammals and nocturnal species. Consequently, we recommend further work to establish the overall reliance of vertebrate taxa on aardvark burrows in arid and semi-arid environments.

We collected data on the demography of cheetahs by direct observation over nine years on Kwandwe Private Game Reserve and by questionnaire on seven fenced reserves in South Africa. Average age at independence was 17.5 months; females gave birth to their first litter of cubs at approximately 27.4 months and the average interbirth interval was 17.8 months. The average litter size at emergence was 4.2 and there was a significant difference between litter sizes at independence on reserves with lions (2.9 cubs) compared to those without (4.7 cubs). Age specific mortality was higher in the first four years of life (40–70%) than year five to nine (0%) and increased after year nine. Mortality of adult cheetahs was higher on reserves with lions compared to those without and there was a significant positive relationship (R2 = 0.56; P < 0.05) between cheetah mortality and the density of large predators on these reserves. We conclude that the reproductive rate of cheetahs that have been reintroduced to fenced reserves is high. Mortality of cubs and young adult cheetahs is elevated in the presence of lions and other carnivores. However, even under these conditions small reserves may serve as a source for cheetahs that can be used to re-stock other areas.

This is a magnificent book that deserves a place on the bookshelves of everyone with an interest, professional or amateur, in the biology of the fauna of Africa. While the focus of the authors might have been on biogeography and taxonomy, and this is emphasized in the title, the species descriptions include information on echolocation and feeding ecology, roosting sites and reproduction. This is far from a dry and difficult to read synthesis of the taxonomy of bats but rather an easy to read consolidation of much of what we know about the bats of southern and Central Africa. In many ways it is an atlas of adaptation and diversity within a single mammalian order. While diversity within the ungulates and carnivores of the region is widely appreciated (because of the size and activity patterns of members of these groups) the same cannot be said for the bats. Their nocturnal activity, small size and habit of roosting in hard to reach places means that they are easily overlooked and even when seen are little more than a blur in the night sky. Bats of Southern and Central Africa: A Biogeographic and Taxonomic Synthesis will go a long way towards rectifying this by providing an easily accessible synthesis of bat diversity.

African Journal of EcologyVolume 47, Issue 3 p. 454-456 Consumption of grass by black rhinoceroses in the Thicket Biome D. M. Parker, Corresponding Author D. M. Parker Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes University *E-mail: d.parker@ru.ac.zaSearch for more papers by this authorR. T. F. Bernard, R. T. F. Bernard Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes UniversitySearch for more papers by this authorB. Fike, B. Fike Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes University Eastern Cape Parks Board, Great Fish River Reserve, PO Box 433, Grahamstown 6140, South AfricaSearch for more papers by this author D. M. Parker, Corresponding Author D. M. Parker Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes University *E-mail: d.parker@ru.ac.zaSearch for more papers by this authorR. T. F. Bernard, R. T. F. Bernard Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes UniversitySearch for more papers by this authorB. Fike, B. Fike Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes University Eastern Cape Parks Board, Great Fish River Reserve, PO Box 433, Grahamstown 6140, South AfricaSearch for more papers by this author First published: 18 August 2009 https://doi.org/10.1111/j.1365-2028.2008.01012.xCitations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume47, Issue3September 2009Pages 454-456 RelatedInformation

Studies concerning the influence of African elephants (Loxodonta africana) on vegetation have produced contradictory results; some show minimal or no effect while others report significant elephant-induced effects. Elephants are generalist megaherbivores but will selectively feed from preferred plant species. We investigated the mortality of aloe plants (highly preferred food items for elephants) at five sites with elephants (treatment) and five paired sites without elephants (control) in the Eastern Cape Province of South Africa. A significantly higher proportion of aloes were dead at treatment sites and significantly more aloes that had lost their crown (headless) were found at treatment sites compared with controls. We conclude that although the proportions of dead aloes at treatment sites were significantly higher, it remains unclear whether there is a need to be concerned with the potential small-scale extinction of aloes from parts of the Eastern Cape Province. The observed mortality may merely be an artefact of the loss of large herbivores through disease (e.g. rinderpest) and hunting in the past.

The impact of elephants (Loxodonta africana) on woody plants is well known. Elephants can be regarded as drivers of ecosystem functioning by, for example, decreasing woody plant litter accumulation through defoliation. However, their influence within grassland landscapes is, by comparison, very poorly understood. We assessed the influence of elephants on grassland functionality at three separate sites (1, high elephant density, long occupation time; 2, low elephant density, short occupation time; 3, no elephants) in the Addo Elephant National Park, Eastern Cape Province, South Africa. Using landscape function analysis (LFA) we described the landscape organisation of each site, and, using visual surrogates, calculated indices of landscape stability, infiltration and nutrient cycling. The number of vegetation patches/10 m of transects surveyed was higher at sites where elephant density was high (3 elephants/km(2)) and where elephants had been present for a long time (>70 years). However, patch size was significantly smaller when elephant density/time of occupation increased, and the proportion of bare soil was higher where elephant density and occupation time were highest. In addition, stability, infiltration and nutrient cycling indices at a site scale were significantly lower where elephants were present at high densities and after a long occupation time. However, bare soil stability was not greatly affected by elephant grazing pressure, implying that a 'threshold of potential concern' has not yet arisen. We conclude that the functioning of this grassland landscape is significantly altered when elephants are present. These conclusions highlight the importance of management factors such as containment and the provision of artificial water points which may be compromising the functionality of these landscapes. We recommend ongoing assessments to inform future management decisions.

We studied space use and habitat selection by elephants in two enclosed reserves in the Eastern Cape Province (South Africa) that conserve components of the regionally important and poorly conserved Thicket Biome. Home ranges of bulls and herds occupied most of the reserves, and core areas were significantly smaller and centred on permanent water. There was no significant difference in home range size of bulls and herds and both were significantly smaller in winter than summer. Components of the Thicket Biome occurred in the home ranges and core areas of all elephants where it was either used according to its abundance or avoided. However, this should not be interpreted as indicating that elephants will not affect plants of the Thicket Biome since change will be cumulative and monitoring should be ongoing to ensure the conservation of this regionally important Biome.

Bushclumps are scattered islands of thicket-like vegetation within a matrix of more open vegetation. We investigated the role of bushclumps as refugia for small mammals, and examined the effect of a limited number of abiotic and biotic factors on their richness, diversity and abundance. Small mammals were surveyed using Sherman small mammal traps at two sites in the Eastern Cape Province, South Africa (Mountain Zebra National Park and Kwandwe Private Game Reserve). Soil hardness and seed abundance, inside and outside bushclumps, were determined. Trap success was significantly higher inside bushclumps than in areas outside, and species diversity and the abundance of small mammals were greater within bushclumps compared to outside. Bushclumps also had significantly softer soil and a higher concentration of seeds. We conclude that bushclumps provide a concentrated source of food and protection from predators for small mammals, and are thus used significantly more than adjacent open areas. The conservation of bushclumps is therefore important for the overall maintenance of ecosystem functioning.

Habitat selection and feeding ecology of a reintroduced population of cheetahs Acinonyx jubatus were studied in a 16 000 ha game reserve in the Eastern Cape Province (South Africa). Seventy per cent of the reserve is characterized by very dense thicket vegetation (valley bushveld) and the remainder is open and savanna-like. The results illustrated a strong effect of sex and group size on the behaviour of cheetahs. The coalition (three adult males) killed significantly larger animals (55% of kills weighed more than 65 kg) than single female cheetahs (less than 2% of kills weighed more than 65 kg). Female cheetahs showed temporal and spatial avoidance of lions by hunting at dawn and dusk and positioning their home ranges [95% utilization distribution (UDs)] significantly farther from the pride of lions than did the coalition. The coalition hunted earlier and later than female cheetahs, and 46% of their kills were made in darkness. In addition, their home range overlapped that of the lions and they showed neither temporal nor spatial avoidance of the lions. The rates of kleptoparasitism were lower and the kill retention times were longer than those reported elsewhere in Africa, and it is suggested that this is a consequence of the cover provided by the thicket vegetation and prey size. The home ranges (95% UDs) of female cheetahs incorporated more thicket vegetation than that of the coalition, indicating that the coalition is less susceptible to predation than single females. These data suggest that cheetahs possess greater behavioural flexibility than previously reported, that they can hunt successfully in thicket vegetation, sometimes in darkness, that they are not restricted to killing small to medium-sized prey, and that they may not be savanna specialists.

There have been few studies on the morphology of spermatozoa of the Cetacea. Here we present a review of the existing published material and present new data for spermatozoa of Kogia breviceps, Kogia sima and Delphinus delphis. In contrast to the usual spiral arrangement of mitochondria in the midpiece of mammalian sperm, cetaceans exhibit a unique arrangement of spherical mitochondria arranged in tiers and columns along the midpiece, which is primitive in appearance. In addition, the midpiece of the cetacean spermatozoon is much shorter than that of other mammalian orders. Detailed knowledge of the morphology of the spermatozoa of cetaceans may help elucidate aspects of male reproduction and the fertilization process in this group.

The objectives of this study were to investigate the effects of prolonged storage of cauda epididymides at 4°C on spermatozoa, and to determine the practicality of utilising epididymal sperm, harvested from testes collected during routine culling of game animals, in assisted reproductive technologies. Testes from eland (Taurotragus oryx) were collected and epididymides removed and maintained at 4°C. Sperm motility, viability, morphology and membrane integrity were examined at 12h intervals for 108h. Sperm motility and viability were significantly lower at the end of the experiment than at the start (P < 0.05) and there was individual variation in the rate at which motility and viability declined. The total number of normal sperm decreased significantly with prolonged storage at 4°C. Midpiece defects were the most common and head and tail abnormalities were rare. A significant decrease in acrosomal and nuclear membrane integrity was observed with prolonged cold storage but there was no significant change in cell membrane integrity. However, about 30% of epididymal sperm survived for 3 days at 4°C and more than 10% survived for 4 days, and it should be possible to use sperm from culled animals in some assisted reproductive technologies.

The effects of winter food supplementation on reproduction in the seasonally breeding four-striped field mouse Rhabdomys pumilio were investigated at Mountain Zebra National Park in the Eastern Cape Province of South Africa. On both control and supplemented grids, reproductive activity in females was inhibited; no pregnant females were collected and juveniles were only present in the first winter month. The provision of additional food resulted in an increase in body mass and mass of the male and female reproductive organs. However, all males, from both grids, were spermatogenically active. Ovarian activity was not stimulated by the provision of additional food, but the development of the uterus was and the endometrium was thicker and more vascularised in mice from the supplemented grid than from the control grid. We conclude that seasonal reproduction in R. pumilio is controlled by the females, in which reproductive activity is inhibited in winter. However, the provision of supplementary food was not sufficient to override the reproductive inhibition.

The diet of Cape clawless otters was assessed at two sites along the Bloukrans River using faecal analysis. Spraints (n = 78) were collected during 2000 and 2001 and analysed using the relative frequency of occurrence and the reconstituted wet weight methods. Both methods found crab (Potamonautes perlatus)l/Ig to be the most important component (>50%) of the diet. Frog, lIgXenopusl/Ig and lIgRanal/ig spp., (11-42%) was the second most important component while fish (Micropteris salmoides)l/Ig was relatively unimportant (<14%). Although the diet of Cape clawless otters in the Eastern Cape Province was similar to that reported elsewhere, the fact that they were preying on an alien invasive fish and not the indigenous endemic Sandelia bainsiil/Ig is significant. The validity of faecal analysis methods is also discussed.

The life history of the springhare (Pedetes capensis, Forster, 1778) at 33 degrees S, in the Eastern Cape Province of South Africa, was characterized by continuous, aseasonal and asynchronous reproduction. Females were monotocous and consecutive pregnancies were separated by a non pregnant period (30-50 days) similar in length to the period of lactation. Young were relatively large at birth (8% of adult bodyweight) but were altricial and only emerged from the burrow at weaning. Towards the end of lactation, many females mated again (20% of all females were both lactating and in early pregnancy) and annual fecundity was probably two but never more than three. For a rodent, albeit a large one, this is a very slow rate of reproduction and we propose that the ricochetal locomotion (jumping on the hind legs) and semi-fossorial life style of the springhare will have resulted in decreased juvenile and adult mortality, and increased longevity, and that these factors have shaped the evolution of the life history of the springhare.

With an increase in the popularity of wildlife ranching in Southern Africa has come the introduction of non-native (extralimital) mammalian herbivores. Financial gain has arguably been at the forefront of these introductions, with little or no assessment of the ecological consequences. The diet of three populations of introduced giraffe Giraffa camelopardalis was assessed by direct observation in the Eastern Cape Province, South Africa between January 2002 and October 2003, as the first step towards understanding the ecological role played by giraffe in the region. Similar to the diet of giraffe within their native range, a deciduous Species from the genus Acacia (Acacia karroo) was the most important species in the diet. Giraffe in the Eastern Cape Province, however, consumed more evergreen species than those within their native range. The relative lack of deciduous species in the Eastern Cape Province provides a probable explanation for such a result. Seasonal variation in the consumption of the most important species in the diet was evident with members of the genus Rhus being more important in the winter months. This was attributed to the deciduous nature of A. karroo. The potential for giraffe to have a detrimental effect oil the indigenous vegetation is discussed. We Conclude that the Study provides a much-needed list of plant species threatened by giraffe browsing in a region where the vegetation is thought to have evolved in the absence of Such a browser.

Giraffe are extralimital in the Eastern Cape Province, South Africa where recent local introductions have persisted despite limited research into their impact on the indigenous flora. The diet of 15 giraffe at the Shamwari Game Reserve was recorded by direct observation during summer (March/April) and winter (July/August) 2001, quantifying diet by frequency of occurrence (individual records scored and expressed as a percentage of the total). Preference indices were also calculated. Habitat use was measured by the number of hours giraffe fed in different habitats. The diet comprised of 14 plant species, the most important species being Rhus longispina (47.9%), Acacia karroo (25.7%) and Euclea undulata (17.6%). Importance of R. longispina, A. karroo and Tarchonanthus camphoratus fluctuated seasonally. Rhus longispina was more important in winter with a corresponding decrease in feeding on A. karroo. Tarchonanthus camphoratus was only consumed during summer. Acacia karroo thickets (previously disturbed areas) were utilized most (summer 12 h; winter 9 h), with alternative habitats utilized more often in winter than in summer. We suggest that the seasonal fluctuation in the importance of R. longispina & A. karroo reflects the deciduous nature of A. karroo.

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 as a solvent for melatonin. Addition of ethanol to the incubation medium altered the pH, and increased pH had a significant negative effect on all aspects of sperm motility. Finally, the overlay of oil, which is a routine part of many sperm culture systems, had an ameliorating effect that was probably because of the lipophilic nature of melatonin.

Eidolon helvum (Megachiroptera) is a large frugivorous bat found in equatorial and tropical Africa. The reproductive cycle is characterized by a three-month period of delayed implantation and the total length of pregnancy may be as much as 10 months. A histochemical study of the gonadotrophs and mammotrophs of the anterior pituitary, in conjunction with assays of LH-like, progesterone-like and prolactin-like immunoreactivity in the plasma suggest that during delayed implantation the gonadotrophs were inactive while the mammotrophs were active and plasma PRL-like immunoreactivity high. We interpret this as indicating that, in the straw-coloured fruit bat, implantation was inhibited by high levels of prolactin and, as such, the endocrine control of delayed implantation may be quite different from that described for other mammals.