Modelling fur seal populations requires the accurate assessment of demographic parameters such as age-specific mortality. Owing to the highly variable mortality rates that pups are subject to, mortality of this age class is perhaps the most important factor determining the number of surviving individuals within each cohort. Early pup mortality,sex ratio and median pupping date were determined for sympatric populations of Subantarctic fur seals (Arctocephalus tropicalis) and Antarctic fur seals (A. gazella) at Marion Island, Southern Ocean. Mortality for this species was density dependent, varying from 0.8% at low density sites to 10.9% at high density sites. More accurate methods employed at low-density sites showed a substantially higher pup mortality at three weeks of 1.3–3.4% for Subantarctic fur seals. The same method yielded a mortality estimate at four weeks of age of 1.1–5.1% for Antarctic fur seals. Despite the underestimate inherent in island-wide counts for Subantarctic fur seals, these estimates are still useful for observing temporal and spatial patterns. Sex ratios were at parity for newborns of both species. The sex ratio of eight-week-old Subantarctic fur seal pups was also at parity, which is unusual for fur seal populations. The median pupping dates determined for Subantarctic fur seals and Antarctic fur seals did not differ substantially from previous estimates.

Echolocation call parameters of six species of rhinolophid and hipposiderid bat species occurring in Swaziland are presented. All calls were obtained with the frequency-division ANABAT bat detector, and mostly from hand-held individuals. There did not appear to be any differences in calls between hand-held and free-flying bats. However, there were significant inter-specific differences with respect to the constant frequency component of the call (equivalent to maximum frequency) and call duration. Minimum frequency was found to be highly variable, and considered not useful for species identification of free-flying individuals. Call parameters obtained in this study are very similar to those obtained with the time-expansion Pettersson detector, suggesting that for this group, choice of detector makes little difference. It is suggested that bat detectors provide an important method to inventory southern African bats, and supplement traditional, capture-based techniques, notably mist nets and harp traps.

The Cape horse mackerel Trachurus trachurus capensis is one of Namibia's most valuable fish stocks, and an important component to the diet of Cape fur seals, Arctocephalus pusillus pusillus, off northern Namibia. The level of overlap in the utilization of this resource between seals and the purse-seine fishery was investigated using two overlap indices. For high overlap measures, seals and the purse-seine fishery utilized age-2 horse mackerel. For low overlap measures, seals mainly consumed age-0 fish whereas the fishery caught age-2 fish. Both indices were adjusted by the proportion of horse mackerel in the seal diet, with the assumption that the proportion consumed by the seals reflects the abundance of horse mackerel in the coastal waters of Cape Cross, Namibia. Both unadjusted and adjusted overlap indices showed that overlap between seals and the fishery in their utilization of juvenile horse mackerel was high only at times when horse mackerel abundance was high, and low when abundance was small. Confidence intervals and significance testing were included. Overall, there was little overlap between seals and the purse-seine fishery. This study provides important information that should be taken into account in the management of the horse mackerel resource.

The small Cape mountain zebra population in Kammanassie Nature Reserve (KNR) is one of three relict Cape mountain zebra populations. Although the genetic diversity of this population is low, it is genetically distinct from the other two populations, the Gamka Mountain Nature Reserve and Mountain Zebra National Park populations, and thus vital for the conservation of this subspecies. The management of the Cape mountain zebra metapopulation requires the mixing of at least some animals from the three relict populations, but this process has been hampered by the relatively slow growth of the KNR population. We investigated the influence of habitat, fire and rainfall on mountain zebra population growth in KNR and used a diffusion model to perform a population viability analysis on the population. Mountain Fynbos covers more than 80% of the reserve but of this, only the Arid Restioid Fynbos and Waboomveld habitats were preferred by mountain zebra. The suitability of these habitats for mountain zebra is, however, highly variable and dependent on fire. The analysis also indicated that the population growth of mountain zebra is related to the incidence of fire and rainfall, but that the stochastic nature of these factors in space and time, limits the growth of the population. Although the population has a low probability of reaching quasi-extinction in the next 50 years (G = 0.123 × 10⁻⁴), we argue that the growth of this population will continue to be slow under the present ‘hands off’ management policy. A number of options to facilitate the growth of this population are considered;changing fire management in the habitat preferred by mountain zebra;acquiring adjacent land; and the translocation of mountain zebra onto adjacent land. Of these options, the latter two need to be implemented as part of a strategy to promote the management of the Cape mountain zebra metapopulation.

The purpose of this study is to analyse the economic impacts of hunting tourism in Namibia. The economic impacts of hunting that takes place in communal land conservancies and on private lands, respectively, are studied, as well as the distribution of these impacts between different sectors and groups in the country. The study is based on data from a survey of hunters who visited Namibia during a five-year period. The income generated by hunting tourism, and the distribution of this income, are analysed using a recently developed Social Accounting Matrix (SAM). In aggregate, an extra N$ in spending by survey respondents translates into approximately one extra N$ in national income, and an average survey respondent's spending raised overall national income by an amount corresponding to two to three years' income for an average Namibian. The additional income generated by hunting tourism and associated tourism benefits rural households and urban wage earners to a greater extent, and capital owners to a lesser extent, than the average income distribution in the economy.

The banana bat, Neoromicia nanus, is characterized by seasonal monoestrous breeding. This study examined the reproductive timing and strategies used by N. nanus in the Province of Mpumalanga, South Africa. Male and female bats were histologically examined to determine their reproductive condition throughout the year. Spermatogenesis in the banana bat began in late September and spermatozoa were released into the caudae epididymides from late April to late July. Spermatozoa remained present in the caudae epididymides throughout August. Mating was initiated in May and ovulation and fertilization occurred at the beginning of August. Implantations first occurred during early August and parturition followed from late October to the end of November. Lactating females were found until mid January. In contrast to the same species in Malawi, it appears that in Mpumalanga no sperm storage takes place in females and occurs for only a short period in males. Reproductive timing was approximately one month earlier in Mpumalanga than in Malawi.

Cape clawless otters, Aonyx capensis, are widely distributed in South Africa, as elsewhere on the continent. They occur in a wide variety of environments and most aquatic habitats, from freshwater lakes to the marine littoral,and even in episodic rivers in arid areas,provided freshwater sources are adequate and sufficient food is available. This animal is not much affected by turbid water as it locates prey by touch, and usually forages close to shores or banks. Evidence of presence in given localities and habitats, distributed over a large area of the Northern, Western, and Eastern Cape provinces, was deduced from signs (faecal deposits or distinctive tracks) on land. Accepting the inherent pitfalls of this approach we nevertheless feel using it is acceptable for a first approximation of habitat preferences over a large geographical area. Results point to areas with dense reed beds and a rocky substrate on banks being used most intensively, probably on account of a localized high food biomass.

Switching from cattle farming to game ranching has become commonplace in the Northern Cape Province. The need to assess the financial implication of such a switch arose from the question of whether game ranching is financially superior to cattle farming in this province. Comparative economics was used in this case study to analyse the profitability, as well as the financial feasibility of three scenarios to determine the financial implications of such a switch. Estimations were based primarily on hunting (biltong and trophy) and live game auctions, the two pillars of the game industry in this province. Results indicate that game ranching can be more profitable, i.e. generate a higher gross margin per hectare than cattle, although not in all cases. Despite this higher profitability, the results indicate further that it is not always financially viable to convert from cattle farming to game ranching, due to the high level of capital investment required. This may have tremendous cash flow implications for the first few years of operation.

Wild mammals in Africa mostly have high levels of innate resistance to haemoparasites and the tick vectors that transmit them. Occasionally though, biotic and abiotic factors combine to alter this relationship and tick-borne disease is diagnosed in wildlife. We postulate an inter-relationship between anthropogenic and natural factors that resulted in wildlife mortality, attributable to disease transmission associated with a gradual build-up of large numbers of ticks. Suppression of grassland fire for 27 years in a distinct ecological unit promoted a gradual expansion of areas covered by tall grass. Changes in composition of the pasture led to improved tick survival, which was further boosted by the availability of increasing numbers of a coarse-grazing species and preferred tick host, African buffalo. Alternating climatic cycles then appeared to precipitate an outbreak of tick-borne haemolytic disease by subjecting ticks and their herbivore hosts to ideal conditions (in wet years) followed by starvation and immune suppression (in dry years). Evidence supporting the hypothesis was gathered retrospectively in the present study through systematic sampling of tick density and correlating life stages of ticks to season, grass species and height of the grass sward. Tick host preference was noted by collection from immobilized wild animals and sympatric livestock. A long series of census data confirmed the changing composition of resident wild herbivores in the Ngorongoro Crater. To reduce the tick challenge, prescribed burning of the crater grassland was reintroduced; tick numbers fell rapidly and three years of subsequent monitoring confirmed the success of this strategy.

Bushbuck (Tragelaphus scriptus) are usually nocturnal, solitary, secretive and inhabit thick bush, making it difficult to estimate its density and abundance. The present study assessed simulated drive counts, distance sampling from sighting efforts, and mark-resighting as estimators of bushbuck population size in valley thicket and coastal bushveld–grassland habitat for management purposes. Sighting efforts using distance sampling during spring were found to be the most effective estimators of bushbuck density and abundance at Shongweni Dam and Game Reserve. Furthermore, the method had high repeatability and simplicity, and low costs. However, continued estimations are required over several years to determine whether these estimations are useful for monitoring population trends of bushbuck.

Spoor measurements of seven subadult black rhinoceroses (Diceros bicornis L.) (three males and four females) were measured during a structured release programme in Matusadona National Park, Zimbabwe. These measurements were then used to test for a relationship between spoor width and length, with the age and weight of the subadult rhinoceroses. In many areas where rhinoceroses occur it is not always possible to obtain visual records, and the ability to accurately assess the age of subadults from spoor will greatly assist management with determining recruitment rates into rhinoceros populations. The efficacy of the immobilization of rhinoceroses in the field would be greatly improved if the weights of subadults were known prior to darting. The results of this study found significant relationships between the spoor measurements and both age and weight, with spoor length being the best predictor variable. There is a need to determine the effect of soil substrate on these relationships. Although the spoor measurements were taken from the same area of ground, suggesting a similar soil substrate throughout, the measurements were taken from both dry and wet soil, depending on the season. It was also found that as the subadults reached maturity, variability in their spoor measurements increased. The results suggest that measuring spoor of subadults in the field could be a valuable management tool for determining recruitment and assessing drug dosages.

Seven emaciated carcasses of wattled starlings were presented to the Poultry Reference Centre, Faculty of Veterinary Science, University of Pretoria. Necropsy findings revealed several large nematode worms which were collected and deposited at the Helminthology Section of the Faculty. The worms were identified as Diplotriaena species. Other lesions were noticed, some of which were believed to be associated with this case of nematodiasis. More investigation and a field visit were made to the site of original collection,with more worms recovered from other dead birds of the same species. Although there have been reported cases of diplotriaeniasis in East, West and North Africa, this is the first time that the worm has been reported from southern Africa.