Mkuzi Game Reserve Research Articles

Human activity and vegetation change around Mkuze Game Reserve, South Africa

In the last century, the establishment of protected areas has become an important part of managing South Africa's wilderness and wildlife. The notion of untouched protected areas has become contested in a time when developing nations are seeking to improve quality of life for their citizens. With the promulgation of modern environmental legislation, resource sharing with local rural communities has become an important policy guideline for protected area management authorities. Census archives and remotely sensed data were used in order to investigate anthropogenic land-cover change around Mkuze Game Reserve between 1979 and 2008. Results showed that natural land cover decreased consistently as populations increased, despite variations in rainfall and population movement. Natural land cover inside Mkuze Game Reserve remained relatively stable. Bush was found to be increasingly degraded around more densely populated areas, while grassland was degrading in districts more concentrated with agricultural activity. A potential problem for future natural resource-dependent livelihoods in the area was the replacement of wetlands with sugarcane agriculture. If current trends continue, natural land-cover loss will continue. Evidence suggests that local socio-environmental systems are changing signifying important implications for the management of human activity and biodiversity around the borders of protected areas in South Africa.

‘The Mkuze River it has crossed the fence’ (1) – communities on the boundary of the Mkuze protected area

Abstract Restricting access to wilderness and wildlife resources is a contested topic in a time when developing nations are seeking to increase quality of life for their citizens. A case in point is the Mkuze Game Reserve which encompasses rich biodiversity and is surrounded by under-resourced rural communities. A history of exclusion from land and resources has left local residents feeling negative about western conservation ideals. Perceptions of protected areas and conservation objectives are important if management authorities are to affect a meaningful buy-in to conservation and sustainable resource use among local residents. In this paper, part of a larger mixed-methods study, we set out to explore the perceptions three rural communities have of 1) local land-cover and livelihood change and 2) the socio-economic benefits expected and derived from living adjacent to Mkuze Game Reserve, a publicly administered protected area in KwaZulu-Natal, South Africa. People living around the reserve felt they receive few benefits from living near to a protected area. Management countered that they are not well funded enough to provide much development support. In addition to this, the community sees a contrast between this lack of benefit sharing and the successful benefit sharing experienced by a neighbouring community which borders a private reserve. This has added to their negative view of the way Mkuze Game Reserve management has been engaging with communities. Effective engagement with communities and understanding their expectations will be important for strengthening conservation initiatives and community engagement objectives in the area.

Spatial fire modeling in Mkuze Game Reserve: A case study*

Controlled burning is a necessary and regular activity in Mkuze Game Reserve, South Africa. Predicting the rate and extent of fire spread in controlled burning operations is, therefore, an important management objective. In this paper we evaluate a cellular automaton model for fire spread in terms of this objective using empirical data for two case studies in Mkuze Game Reserve. Incorporating data relating to factors such as temperature reduction in the early evening, subsequent dew formation and increased fuel moisture content, the model was found to closely resemble the observed fire behaviour.

Limited mitochondrial DNA variation within South Africa's black rhino (Diceros bicornis minor) population and implications for management

AbstractThe taxonomy of African black rhinoceros (Diceros bicornis) remains unresolved. Maintaining levels of genetic diversity and species rescue by reintroduction and restocking requires its resolution. We compared the sequences of the mitochondrial DNA (mtDNA) control region for a total of 101 D. bicornis from three subspecies: D. b. minor, D. b. michaeli and D. b. bicornis. A single unique haplotype was found within the 65 D. b. minor samples from KwaZulu‐Natal (KZN) Province, South Africa, 55 of which came from Hluhluwe‐iMfolozi Game Park (HiP) and Mkuzi Game Reserve (MGR) source populations. However, six different haplotypes were represented in eleven D. b. minor samples from Zimbabwe. Similarly, published autosomal microsatellite data indicate low levels of diversity within the KZN D. b. minor populations. The low levels of mtDNA diversity within the KZN metapopulation point to the possible need for genetic supplementation. However, there is a need to determine whether the low levels of genetic variation within KZN D. b. minor are a result of the recent bottleneck or whether KZN historically always had low diversity.

Determinants of inter-annual variation in the area burnt in a semiarid African savanna

Fire is a key driver of savannas. It was predicted that the area of a summer-rainfall savanna burnt per annum should depend on the amount of fuel, which depends on variable grass production resulting from variable rainfall, ‘carry-over’ from the preceding season and attrition of fuel by herbivores. Most fires occur during the dry season, thus the amount of green growth resulting from occasional winter rainfall could influence fuel combustibility and therefore the area burnt. These predictions were examined with a 37-year (1963–99) data set for Mkuzi Game Reserve, South Africa. Total area burnt was related to wet season rainfall separately for years with a ‘wet’ dry season or a ‘dry’ dry season. Against prediction, the amount of dry-season rainfall had no influence on the total area burnt. For years with a ‘dry’ dry season, rainfall of the preceding wet season had an additional influence. Herbivore density had no influence. A dry-season burn was twice as large as a wet-season burn, and the largest burns were the most intense. Monitoring of wet season rainfall is sufficient for planning burning programs. Intense, large fires can be achieved for control of bush encroachment following 2 or more successive years of high rainfall.

Determinants of spatial variation in fire return period in a semiarid African savanna

Fire pattern is predicted to vary across an African savanna in accordance with spatial variation in rainfall through its effects on fuel production, vegetation type (on account of differences in fuel load and in flammability), and distribution of herbivores (because of their effects on fuel load). These predictions were examined for the 23 651-ha Mkuzi Game Reserve, KwaZulu-Natal, based on a 37-year data set. Fire return period varied from no occurrence to a fire every 1.76 years. Approximately 75% of the reserve experienced a fire approximately every 5 years, 25% every 4.1–2.2 years and less than 1% every 2 years on average. Fire return period decreased in relation to an increase in mean annual rainfall. For terrestrial vegetation types, median fire return periods decreased with increasing herbaceous biomass, from forest that did not burn to grasslands that burnt every 2.64 years. Fire was absent from some permanent wetlands but seasonal wetlands burnt every 5.29 years. Grazer biomass above 0.5 animal units ha–1 had a limiting influence on the maximum fire frequency of fire-prone vegetation types. The primary determinant of long-term spatial fire patterns is thus fuel load as determined by mean rainfall, vegetation type, and the effects of grazing herbivores.

Landscape-level differences in fire regime between block and patch-mosaicburning strategies in Mkuzi Game Reserve, South Africa

Patch-mosaic burning (PMB) is commonly advocated to create a mosaic of fire regimes that is believed to be more beneficial for maintaining biodiversity than the relatively homogeneous environment produced by block burning. This premise was examined for the 23 651 ha Mkuzi Game Reserve, in which all fires have been mapped for a period of block burning (1966–1984) and for a period of PMB (1985–1999), using a geographic information system. Patch-mosaic burning met with the expectation of creating a more heterogeneous fire regime as evidenced by a four-fold increase in average fire frequency, a greater area of reserve burnt per annum, an increase in the perimeter-to-area ratio of individual burns, and a greater proportion of fires occurring throughout the dry season as opposed to being concentrated toward the end of the dry season. In contradiction of expectation, size of individual burns did not differ between strategies, both periods were characterised by intense fires, and natural barriers to fire did not increase in importance under PMB. There was a reduced importance of arson fires and a markedly increased proportion of prescribed burns under PMB. Patch-mosaic burning has met in part its objective of creating a more heterogeneous fire regime.

Molecular monitoring of African swine fever virus using surveys targeted at adult Ornithodoros ticks : a re-evaluation of Mkuze Game Reserve, South Africa

The Mkuze Game Reserve (MGR), in north-eastern KwaZulu-Natal Province, South Africa is an African swine fever virus (ASF) controlled area. In a survey conducted in 1978, ASF prevalence in warthogs and Ornithodoros ticks in MGR was determined to be 2% and 0.06%, respectively. These values, acknowledged as being unusually low compared to other East and southern African ASF-positive sylvatic-cycle host populations, have not been assessed since. The availability of a sensitive PCR-based virus detection method, developed specifically for the sylvatic tampan host, prompted a re-evaluation of ASF virus (ASFV) prevalence in MGR ticks. Of the 98 warthog burrows inspected for Ornithodoros presence, 59 (60.2%) were found to contain tampans and tick sampling was significantly male-biased. Whilst gender sampling-bias is not unusual, the 27% increase in infestation rate of warthog burrows since the 1978 survey is noteworthy as it anticipates a concomitant increase in ASFV prevalence, particularly in light of the high proportion (75%) of adult ticks sampled. However, despite DNA integrity being confirmed by internal control amplification of the host 16S gene, PCR screening failed to detect ASFV. These results suggest that ASFV has either disappeared from MGR or if present, is localized, occurring at exceptionally low levels. Further extensive surveys are required to establish the ASFV status of sylvatic hosts in this controlled area.

Polystomatidae (Monogenea) of African Anura: Polystoma dawiekoki n. sp. parasitic in Ptychadena anchietae (Bocage).

Polystoma dawiekoki n. sp. is described as a new species of the Polystomatidae parasitic in the urinary bladder of the plain grass frog Ptychadena anchietae. This parasite was collected at Mkuze town and Mkuze Game Reserve in northern Kwazulu-Natal Province, in the Kruger National Park in Mpumalanga Province, South Africa, and at Bulwa in Tanga Province, East Usambara Mountains, Tanzania. It is distinguished from other African Polystoma species by a combination of characters, including the body size, size and shape of marginal hooklets and the haptor length to body length ratio. The presence of adult, as well as subadult, parasites in the same individuals, as is known for Eupolystoma, represents a significant evolutionary departure from the pattern of transmission typical of Polystoma in most of the other anuran hosts.

An improved cellular automaton model for simulating fire in a spatially heterogeneous Savanna system

Developments in and around game reserves and ranches in South Africa have led to controlled burning becoming a necessary and regular activity. The management objectives of these fires are well-defined, and thus predicting the duration and extent of a burn is vitally important. Testing scenarios via computer simulation is desirable since this removes the potential risks associated with fire, whilst at the same time ensuring that management policies are attained. There are various approaches to developing a spatial simulation fire model. In this article we present a cellular automaton (CA) model that is capable of predicting fire spread in spatially heterogeneous Savanna systems. The physical basis of Rothermel's fire spread model (1972) was modified to a spatial context and used to improve the CA model introduced by Karafyllidis and Thanailakis (1997). The proposed fire model was verified using data for three human-induced fires in the Mkuze Game Reserve, South Africa, and was found to satisfactorily predict spatial fire behaviour.

Using models in the management of Black rhino populations

A study was undertaken, modeling Black rhino, Diceros bicornis, populations from Hluhluwe-Umfolozi Game Reserve and Mkuzi Game Reserve, Republic of South Africa. This study had two specific goals. Firstly, we tried to find a simple model to predict the population number in the following year and give insight in the number of animals that can be removed from the population. Secondly, the use of different models gave us the opportunity to evaluate the effect of small differences in model structure on the outcome of the models. Five different models were tested, mainly focusing on the structure of density dependence. The density dependent model, that incorporated stronger density dependence at high densities, fitted best to the observed census values. The study, furthermore, indicated that the population in Hluhluwe-Umfolozi is stabilizing. The situation in Mkuzi was not that clear. Based on these results, managers should therefore be more careful with removing animals from this population. Finally the results clearly showed that different model structures can result in very different model outcomes. Besides in the values of the model parameters, this was also shown by different values for the population number where the yearly increase is maximal. Based on these results it does not seem wise to base management decisions solely on the outcome of one model. Therefore, we strongly encourage managers to compare the outcome from different model structures, based on different biological assumptions.

Welfare Implications of the Night Shooting of Wild Impala(Aepyceros Melampus)

AbstractThe most common method of culling impala(Aepyceros melampus)and many other antelope species in Africa was evaluated from a welfare point of view. The culling of 856 impala from 401 herds was observed and recorded in the Mkuzi Game Reserve, South Africa. Ninety-three per cent of animals were killed instantaneously by the first shot. Results indicated that herd size and composition, distance of herd from hunting vehicle and shot number all have a bearing on the number of animals wounded and missed. It is concluded that the culling of free-ranging impala by night-hunting in the manner described is a satisfactory method on welfare grounds, although a number of recommendations are made which might render the culling process more humane. It is argued that economic and welfare considerations are not necessarily in conflict, and long-term efficiency is likely to be enhanced by addressing both simultaneously.

Optimising the offtake of large herbivores from a multi-species community

The Natal Parks Board annually sells hunting licences for the Controlled Hunting Area (CHA) adjacent to the Mkuzi Game Reserve. A management objective is to maximise the revenue obtained from these hunting activities while ensuring that the population of each species is kept above some minimum level. This management problem is formulated as a linear programming problem and solved for the fourteen different species in the CHA. The LP problem is formulated in such a way as to utilise the same data that is the basis for present management decision-making. The objective function takes into account that animals are hunted for both meat and trophies. Only a fraction of each population is suitable for trophy hunting and higher prices are usual for such animals. The model considers fourteen species divided according to their food preferences into four groups. There is a carrying capacity constraint which limits the weighted sum of the populations in each of these groups. Further constraints relate to the specific growth rates of each species. The optimal equilibrium population levels were calculated to serve as goals or targets. However, droughts and other natural phenomena which affect population numbers are frequently encountered at Mkuze. A number of experiments were therefore performed where the populations were set to reduced levels. The optimal control problem which steers the populations towards the target levels in an optimal way was formulated. Some illustrative solutions are presented.

Who is Responsible for Fission in a Free‐ranging Troop of Baboons?

AbstractThe study troop of chacma baboons (Papio cynocephalus ursinus) at Mkuzi Game Reserve, Zululand, South‐Africa, comprised of about 76 members that split into two new troops. The events leading to this troop fission will be described and its possible causes will be discussed.Troop fission among baboons is generally attributed to the withdrawal of low‐ranking females from the main group, as a result of the cost of food competition and its effect on their reproductive success. At Mkuzi, no evidence for food competition among females was recorded in terms of rank‐related time spent feeding or other time—budget components, feeding‐bout length, diet composition or context of female aggression. Moreover, no evidence for rank‐related differential reproductive success was found in terms of inter‐birth intervals or infant survival. Female mortality was, however, related to dominance rank, with circumstantial evidence suggesting that cause of mortality was predation by leopards. Rate of female disappearances, aggression levels among females, and the percentage of time they spent in proximity to other adult troop members increased after fission.Relatively short inter‐birth intervals and extremely low infant mortality rate at Mkuzi resulted in a small number of receptive females at any one time, and therefore in high costs of male sexual competition as expressed in the high levels of male aggression and woundings, both reduced after fission.It is suggested that this troop fission may have been initiated by the resident males, triggered by the high cost of sexual competition, and forced on the females, who were, consequently, subjected to higher risk of predation. The troop fission was preceded by a long process of increasing tendency for sub‐trooping. It was initiated by the four resident males who kept a large distance apart from each other, herded oestrous female associates away from others and were followed by other females. The females generally tended to stay close to associates, males and females. These parties were followed by the peripheral and immigrant males who had no female associates, and eventually two distinct daughter troops were formed.

Do Female Chacma Baboons Compete for a Safe Spatial Position in a Southern Woodland Habitat?

AbstractIn this study troop of chacma baboons (Papio cynocephalus ursinus) at Mkuzi Game Reserve, Zululand, South-Africa, it is suggested that risk of predation and competition over safe spatial position had more importance and effect on female behaviour than did competition for food. Only 6.4% of all agonistic events were over food patches and no significant correlation was found between a female's dominance rank and proportion of time spent feeding, feeding bout length or diet composition. Parameters of reproductive success, such as inter-birth intervals and infant mortality were not correlated with female dominance rank. Female mortality, however, was related to dominance rank and all of the five females who disappeared during the study were low-ranking. Four of the five females disappeared after troop fission. There is circumstantial evidence supporting the suggestion that predation by leopards is the main cause of mortality of females at Mkuzi. High levels of female aggression were recorded, with almost no occurrences of support coalitions. Most of the aggression took place among similar ranking females, or was directed by the top ranking toward the lowest ranking females. Most of the female-to-female agonistic encounters were in a social context, and more than half were over a spatial position next to other adult troop members. Aggression among females increased after troop fission. It is suggested that the higher-ranking females may be better protected from predation, through access to more central spatial positions in the troop. Indeed, a positive correlation was found between a female's dominance rank and the time spent next to other adult troop members. It may be that avoiding food competition by keeping larger distances from others, while foraging, was translated in lower ranking females to a cost of higher predation risk.

Seed structure and germination of Dichrostachys cinerea

Dichrostachys cinerea (L.) Wight et Arn. (Legume: Mimosoideae) is a major contributor to the bush encroachment problem in Mkuzi Game Reserve. Seed characteristics were examined so that ecological and managerial concepts could be evaluated. Dormancy is imposed by the smooth, hard and impermeable testa. Scarification or cracks in the testa allow imbibition through the lens, which is followed by germination. The percentage germination of Dichrostachys cinerea is higher in light than in dark and there is a loss of temperature sensitivity with time. The behaviour of Dichrostachys cinerea seeds is not as that typically reported for mimosoid seeds, since germination improved with storage, and light enhanced germination of scarified seeds. This has important ecological implications, since seeds would germinate easier where the canopy has been removed or the soil has been disturbed. Dichrostachys cinerea (L.) Wight et Arn. (Legume: Mimosoideae) is ‘n belangrike bydraer tot die bos- indringerprobleem in die Mkuzi Wildreservaat. Saadkaraktertrekke is bestudeer sodat ekologiese en bestuurskonsepte geëvalueer kon word. Saadrus word veroorsaak deur die gladde, harde en waterdigte testa. Skarifikasie en barste in die testa laat imbibisie deur die lens toe sodat ontkieming kan plaasvind. Die persentasie ontkieming van Dichrostachys cinerea is hoër in die lig as in die donker en daar is ‘n verlies van temperatuursensitiwiteit met tyd. Dichrostachys cinerea sade reageer nie soos verwag word van mimosoidsade nie, aangesien ontkieming met opberging verbeter het, en lig die ontkieming van geskarifiseerde sade verhoog het. Hierdie aspek het belangrik ekologiese implikasies omdat sade beter sal ontkiem waar die plantegroei verwyder of die grond versteur is.

Gastro‐intestinal helminth parasites of the chacma baboon, Papio cynocephalus ursinus, from the coastal lowlands of Zululand, South Africa

SummaryAn examination of 191 faecal samples from Papio cynocephalus ursinus from Mkuzi Game Reserve, Natal, South Africa, has revealed low prevalence rates for a high diversity of gastro‐intestinal helminths. This high diversity, including the first evidence for an acanthocephalan infection in South African baboons, is compared to that from montane baboons studied previously.

Maternal care of a single offspring in the dung beetleKheper nigroaeneus: the consequences of extreme parental investment

The nesting biology of Kheper nigroaeneus, a large diurnal ball-rolling dung beetle, was studied in Mkuzi Game Reserve, South Africa. On each nesting occasion a female reared a single offspring from egg to adult in an underground nest. During the first two weeks of nesting the female fed on the outside of the brood ball, reducing its volume by 60%. The larva required only 17% of the ball for development. Female K. nigroaeneus remained physiologically prepared to develop a second egg and hence initiate a new nest, if the first was unsuccessful, for about three weeks after oviposition. Thereafter they resorbed the second and any subsequent oocytes. Offspring survival was between 58% and 84% for egg to adult. The sexual strategies of both sexes are discussed, with particular consideration given to the question of why the male deserts the nest before oviposition.

Field ecology of a brood-caring dung beetleKheper nigroaeneus-habitat predictability and life history strategy

The life history strategy of the dung beetleKheper nigroaeneus was studied in Mkuzi Game Reserve, South Africa.K. nigroaeneus, a large ball-rolling dung beetle, brood-cares a single offspring per nesting occasion. Adults emerged from the ground following the first spring rain (≥17 mm) in October or November, occasionally September, and trap catches were at a maximum 1-2 weeks later. Females outnumbered males by 3:1 at the time of maximum catches, but thereafter declined steadily, as the numbers of females involved in brood-care increased. Brood-care lasted 12 weeks, and parental females then (a) entered a second brood-care period, or (b) remained underground in diapause, or (c) emerged to feed. Reproductive activity stopped after February, ensuring that the entire population reached the adult stage by winter. Females active above ground after February, in reproductive diapause, had low fat levels and resorbed oocytes. Females buried underground, in reproductive diapause prior to and during winter, had high fat levels, resorbed oocytes, a reduced metabolic rate and empty guts. The Mkuzi habitat is predictable forK. nigroaeneus in spring, since only one good fall of rain is sufficient to drive population events for the next three months. In the latter half of the season the life history ofK. nigroaeneus is more flexible, and hence less constrained by climate.