White Rhinoceros Ceratotherium Simum Research Articles

Grazing in a megagrazer‐dominated savanna does not reduce soil carbon stocks, even at high intensities

Recent studies suggest that wild animals can promote ecosystem carbon sinks through their impacts on vegetation and soils. However, livestock studies show that intense levels of grazing reduce soil organic carbon (SOC), leading to concerns that rewilding with large grazers may compromise ecosystem carbon storage. Furthermore, wild grazers can both limit and promote woody plant recruitment and survival on savanna grasslands, with both positive and negative impacts on SOC, depending on the rainfall and soil texture contexts. We used grazing lawns in one of the few African protected savannas that are still dominated by megagrazers (> 1000 kg), namely white rhinoceros Ceratotherium simum, as a model to study the impact of prolonged and intense wild grazing on SOC stocks. We contrasted SOC stocks between patches of varying grazing intensity and woody plant encroachment in sites across different rhino habitat types. We found no differences in SOC stocks between the most‐ and least grazed plots in any of the habitats. Intermediately grazed plots, however, had higher SOC stocks in the top 5 cm compared to most and least grazed plots, but only in the closed‐canopy woodland habitat and not in the open habitats. Importantly, we found no evidence to support the hypothesis that wild grazing reduces SOC, even at high grazing intensities by the world's largest megagrazer. Compared to the non‐encroached reference plots, woody encroached plots had higher SOC stocks in soils with low clay content and lower SOC stocks in soils with high clay content, although only in the top 5 cm. Accordingly, our study highlights that wild grazers may influence SOC indirectly through their impact on tree‐grass ratios in grassy ecosystems. Our study thus provides important insights for future natural climate solutions that focus on wild grazer conservation and restoration.Keywords: fire, grazing impact, rewilding, soil carbon, white rhinoceros, woody encroachment

Simulated elephant-induced habitat changes can create dynamic landscapes of fear

Landscapes of fear have become widely studied in the northern hemisphere, but are still largely understudied in the more complex, diverse carnivore-prey communities of Africa. Habitat changes brought about by a megaherbivore, the African elephant (Loxodonta africana), can modify the perceived landscape of fear by predation vulnerable prey species (impala Aepyceros melampus and warthog Phacochoerus africanus) in contrast with non-prey species (white rhinoceros Ceratotherium simum). We hypothesized that by opening up woody vegetation, elephants may modify perceived risk at a landscape-scale, but also at a fine scale by depositing escape impediments in the form of coarse woody debris. We experimentally tested this in Hluhluwe-iMfolozi Park, South Africa, by simulating elephant-induced habitat changes on patch scale (opening up woody vegetation) and within-patch scale (deposition of coarse woody debris) and monitoring the herbivore visitation using camera traps. We compared visitation on the edge of grazing lawns (in proximity of dense vegetation) and the centre (open, highly visible patches), either with or without coarse woody debris and with or without fresh predator scat. We found that mesoherbivore prey species showed contrasting responses, with warthog avoiding plots close to dense vegetation and plots with coarse woody debris. Impala reduced their visitation to dense vegetation patches only during risky times, at night, especially in the presence of predator scat, but did not clearly avoid plots with coarse woody debris. Our study indicates that, in African savannas, the perceived landscape of fear is a highly dynamic phenomenon varying in both space and time and being species-specific. Elephant induced habitat changes may shape landscapes of fear in complex and contrasting ways.

A new species of Kiluluma Skrjabin, 1916 (Nematoda: Strongyloidea) from the white rhinoceros, Ceratotherium simum (Burchell) from South Africa.

A new species of Kiluluma Skrjabin, 1916, Kiluluma ornata n. sp., is described from the intestine of the white rhinoceros Ceratotherium simum (Burchell) from South Africa. The new species is virtually identical with a species described as Kiluluma sp., but not named due to a paucity of material then available. The new species most closely resembles K. solitaria Thapar, 1924 and K. ceratotherii Beveridge & Jabbar, 2013, in the possession of an undulating anterior margin of the buccal capsule but differs in the leaf crown elements which have bulbous, lip-like expansions, which are lacking in K. solitaria and K. ceratotherii.

Rhinoceros horns in trade on the Myanmar–China border

AbstractThe illegal trade in rhinoceros horn, driven largely by the demand from East and South-east Asia, is a major impediment to the conservation of rhinoceroses globally. We surveyed the town of Mong La, in eastern Myanmar on the border with China, for the presence of rhinoceros horn. No rhinoceros horn was observed in 2006 or 2009, and other African wildlife was rare or absent. During visits in 2014 and 2015 we observed two horns, presumed to be of the white rhinoceros Ceratotherium simum, and one horn tip, small discs from the horn core, horn powder and horn bangles. Shops selling rhinoceros horn all specialized in high-end and high-value wildlife, mostly for decorative purposes, including whole elephant tusks, carved elephant ivory, carved hippopotamus Hippopotamus amphibius canines, and tiger Panthera tigris skins. Organized criminal syndicates are involved in the wildlife trade between Myanmar and Africa, possibly via China. Mong La's geographical position on the border with China, limited control by the central Myanmar Government, and the presence of the Chinese entertainment industry provide ideal conditions for a global wildlife trade hub catering for the Chinese market. Solutions require more intense collaboration between the Myanmar and Chinese authorities to curb the trade in African rhinoceros horn in this part of Asia.

Analysis of the European captive Southern white rhinoceros Ceratotherium simum simum population using the International Studbook for the African White Rhinoceros (2001–2004) and integrating reproductive health findings

The goal of ex situ conservation is to maintain genetic diversity, avoid inbreeding and maximize equal representation of founder individuals. Analysis of a well‐maintained studbook yields important data concerning fertility and mortality that is invaluable to ex situ conservation. To evaluate the reproductive status of the European captive Southern white rhinoceros Ceratotherium simum simum population, basic demographics and population parameters were calculated using the International Studbook for the African White Rhinoceros Ceratotherium simum (2001–2004) data with the integration of recent scientific findings regarding reproductive health of individuals within the ‘reproductive age’. Kinship analysis of the 2001–2004 population was also performed to evaluate genetic diversity. Results indicated the population is declining 1·19 times faster than it is growing. To realize a 1% population increase at the 2001–2004 death rate, reproduction would have to increase by 214%. It is necessary to increase the genetically contributing subpopulation and to achieve a reproduction capacity that surpasses the rate currently possible with natural mating.

Same-site multiple releases of translocated white rhinoceroses Ceratotherium simum may increase the risk of unwanted dispersal

The Near Threatened white rhinoceros Ceratotherium simum went extinct in Botswana during the 20th century because of poaching. Several attempts have been made to reintroduce the species. From 2001 to 2003 four batches (a total of 32 individuals) of white rhinos were released in the Moremi Game Reserve. All were fitted with transmitters, ear notched and monitored on a regular basis. Rhinos released in the last batch moved significantly further from the release site compared to early batches. Six female rhinos from the last batch dispersed out of the Reserve. Activity area (95% minimum convex polygon; MCP) sizes decreased with years after release and increasing density of rhinos but only density had an effect on the core area (50% MCP) sizes. We conclude that the number of rhinos present in the area of release should be carefully considered before further individuals are released. When released in an area with rhinos that have established territories, the newly reintroduced individuals may be forced to disperse. If other areas of suitable habitat are available elsewhere in the same protected area, animals should be released at different sites to avoid unwanted long-term dispersal and to use the inverse density-dependent activity area sizes to maximize the rhino population in an area.

THE VOCAL REPERTOIRE IN NORTHERN WHITE RHINOCEROS CERATOTHERIUM SIMUM COTTONI AS RECORDED IN THE LAST SURVIVING HERD

ABSTRACT The Northern White Rhinoceros Ceratotherium simum cottoni is a subspecies of the White Rhino that is almost extinct in the wild. We studied the last reproducing herd kept in Zoo Dvur Kralove to describe its vocal repertoire. The calls produced by eight individuals were recorded and analysed as concerned both sound properties and behavioural contexts in which they were emitted. We distinguished 11 calls belonging to four categories: (1) tonal harmonic sounds, (2) puffing sounds, (3) growling sounds, and (4) repetitive sounds. We found an apparent similarity between acoustic parameters of homologous calls recorded in both white rhino subspecies. We further confirmed that the repertoire of white rhino calls is much larger than that reported in other rhino species. We tentatively interpret this finding as an adaptation to increased sociality. Four calls reach the infrasound range; nevertheless, they are probably not used for communication over distance. This is obvious in the case of the grouch call, which contains the highest infrasound component. There are, however, other candidates for such a communication function: the repetitive pant sound, which is not known in other rhino species. We hypothesise that the repetitions may enhance their audibility in the typical open habitats of white rhinos.

Diets of savanna ungulates from stable carbon isotope composition of faeces

AbstractHypotheses to explain diversity among African ungulates focus largely on niche separation along a browser/grazer continuum. However, a number of studies advocate that the browser/grazer distinction insufficiently describes the full extent of dietary variation that occurs within and between taxa. Disparate classification schemes exist because of a lack of uniform and reliable data for many taxa, and failure to incorporate spatio‐temporal variations into broader assessments of diet. In this study, we tested predictions for diet and dietary niche separation of African savanna ungulates using stable carbon isotope evidence from faeces for proportions of C3 (browse) to C4 (grass) intake among 19 species from the Kruger National Park, South Africa. Dietary predictions from the literature are confirmed in the case of browsers (black rhinoceros Diceros bicornis, giraffe Giraffa camelopardalis, bushbuck Tragelaphus scriptus, kudu Tragelaphus strepsiceros), mixed‐feeders (impala Aepyceros melampus, nyala Tragelaphus angasii), and most grazers (white rhinoceros Ceratotherium simum, Burchell's zebra Equus burchellii, warthog Phacochoerus africanus, hippopotamus Hippopotamus amphibius, blue wildebeest Connochaetes taurinus, tsessebe Damaliscus lunatus, waterbuck Kobus ellipsiprymnus). In contrast, several species showed results differing from most expectations derived from the available literature, including eland Taurotragus oryx, steenbok Raphicerus campestris, grey duiker Sylvicapra grimmia, buffalo Syncerus caffer, roan antelope Hippotragus equinus and sable antelope Hippotragus niger. Many of these discrepancies can be accounted for by seasonal and/or regional dietary differences. Cluster analysis based on a data matrix that incorporates the extent of spatio‐temporal dietary variation among Kruger Park ungulates reveals several distinct categories of feeding preferences that extend beyond a two‐edged browser/grazer dichotomy, such as mixed‐feeders with a preference for either forage class, and spatial/seasonal shifts between uniform and mixed‐feeding styles among variable browsers (e.g. grey duiker) and variable grazers (e.g. buffalo). These results highlight the need for approaches that are sensitive to spatio‐temporal variations and the continuity of diet.

The effect of grassland shifts on the avifauna of a South African savanna

Two distinct grassland types occur within Hluhluwe-iMfolozi Park (HiP): short stoloniferous grazing lawns and tall, tussock-like 'bunch' grasslands. Grazing lawns are maintained by grazing mammals, among which White Rhinoceros Ceratotherium simum is of major importance. By contrast, tall bunch grasslands are promoted by frequent burning. The extent of each grassland type within the park is highly dynamic and can be altered by changes in mammal numbers and/or fire regimes. Such changes may have cascading consequences for other components of the ecosystem if they show specialisation towards one or other grassland state. This study compared avifaunal assemblages of grazing lawns and bunch grasslands to assess how bird species of the park might change with shifts in the grassland mosaic. Distinct bird communities were associated with each grassland type, including several specialists, and bird distribution was linked to vegetation structure rather than floristics. Post-fire bunch grasslands provided ephemeral habitats for short-grass specialists. Outside HiP, domestic livestock produced structurally-similar grasslands to grazing lawns and bunch grasslands, but heavy predation of birds by people reduced bird densities. Because HiP is surrounded by such communal grazing lands, the park is of key importance in conserving grassland birds on a regional scale, a factor that needs to be considered in managing the park's grassland mosaic.

A review of the reproductive physiology of rhinoceros species in captivity

Substantial progress in understanding the reproductive physiology of the four rhinoceros species in captivity, White rhinoceros Ceratotherium simum, Black rhinoceros Diceros bicornis, Indian or Greater one‐horned rhinoceros Rhinoceros unicornis and Suma‐tran rhinoceros Dicerorhinus sumatrensis, has been achieved over the last two decades largely owing to advances in endocrine and ultrasound techniques, and improved methods of semen collection. Primarily through the non‐invasive monitoring of hormone metabolites, scientists have studied the reproductive cycle, investigated the effects of season and potential stressors, and diagnosed pregnancy in each species. By employing the powerful tool of ultrasonography, more detailed and accurate information regarding reproductive function has been revealed. Important findings include anovula‐tory cycles, induced ovulation, reproductive tract pathologies, early pregnancy diagnosis and early embryonic loss. Interest in the reproductive physiology of c? rhinoceros has lagged behind that of ♀♀ but in recent years data on sperm and semen characteristics, reproductive glands and hormone production have been collected. While the reproductive physiology of each rhinoceros species is interesting in its own right, perhaps most fascinating is the significant inter‐specific variation in reproductive traits within this taxon.

Rhinoceros behaviour: implications for captive management and conservation

All species of rhinoceros are, to varying degrees, threatened with extinction because of poaching, habitat loss, human‐rhinoceros conflict, hunting and civil unrest. Clearly the threats facing the five remaining species (Black rhinoceros Diceros bicornis, White rhinoceros Ceratotherium simum, Greater one‐horned rhinoceros Rhinoceros unicornis, Javan rhinoceros Rhinoceros sondaicus and Sumatran rhinoceros Dicerorhinus sumatrensis) are anthropogenic. Although many disciplines are important for conservation, understanding the behaviour characteristics of a species should be considered a key component when developing wildlife‐management and conservation strategies. A general overview of the behaviour of rhinoceros is presented, addressing ecology and social organization, activity and habitat use, feeding strategies, courtship and reproduction, and anti‐predator behaviour. The implications of behavioural studies for successful management and husbandry of rhinoceros in captivity are discussed in sections on group size and composition, enclosure design and enrichment programmes, activity patterns, introductions, reproduction, hand‐rearing, and health and stress. Finally, there is some discussion about the implications of this knowledge for in situ conservation in relation to designing protected areas, further aspects of animal health and stress, and reintroduction and translocation. A detailed understanding of rhinoceros behaviour is important for survival both in range‐country protected areas and captivity, and such knowledge should be used to provide the most appropriate animal care and environments for these species.

Population management of rhinoceros in captivity

Captive‐breeding programmes are important components of conservation strategies for rhinoceros. Rhinoceros in zoos can serve as (1) genetic and demographic reservoirs to reinforce wild populations as the need and opportunity occur, and (2) ambassadors to increase public awareness and support, especially financial, for conservation of wild populations. However, for these functions, rhinoceros in captivity must be managed scientifically and co‐operatively to produce viable populations. Population‐management programmes for Black rhinoceros Diceros bicornis, White rhinoceros Ceratotherium simum and Indian rhinoceros Rhinoceros unicornis are operating in various regions of the zoo world, especially North America [Species Survival Plans (SSP)] and Europe [European Endangered Species Programmes (EEP)]. Analyses indicate that rhinoceros populations in captivity are achieving variable levels of viability. In SSP and EEP populations Black rhinoceros and White rhinoceros are genetically but not demographically satisfactory, while Indian rhinoceros is healthy demographically but limited genetically. Improvement is needed and could be achieved through better management.

Evaluating population persistence of censused and unmanaged herbivore populations from the Kruger National Park, South Africa

The application of the Dennis et al. ( Ecol. Monogr., 61, 1991) model to data from 12 herbivore populations from the Kruger National Park, South Africa, introduces ‘risk assessment’ procedures into the conservation management of free-ranging species. The model enables one to predict the probability of reaching an arbitrarily defined threshold population size using census figures from censused and unmanaged populations. It also provides an objective evaluation of population persistence based on past performance. Of the 12 species investigated, five (impala Aepyceros melampus, blue wildebeest Connochaetes taurinus, zebra Equus burchelli, white rhinoceros Ceratotherium simum, giraffe Giraffa camelopardalis) appear to be secure, four (kudu Tragelaphus strepsiceros, waterbuck Kobus ellipsiprymnus, warthog Phacochoerus aethiopicus, sable antelope Hippotragus niger) are vulnerable and three species (tsessebe Damaliscus lunatus, eland Taurotragus oryx, roan antelope Hippotragus equinus) are at risk of declining by an order of magnitude within 100 years. Therefore, within data limitations, the KNP appears not to offer sufficient suitable habitat for a number of herbivore species despite its considerable size, and a metapopulation approach may be required for the effective conservation of some species. The model also allows the principle of ‘complementarity’ to be extended beyond that of species composition. Objective evaluations of population persistence, of censused and unmanaged populations, as demonstrated here, mean that the principle of ‘population viability’ can help the design of efficient regional reserve networks.

Population characteristics and management of black rhinoceros Diceros bicornis minor and white rhinoceros Ceratotherium simum simum in Ndumu Game Reserve, South Africa

The population sizes, sex and age structures, home range sizes and overlap were determined for black rhinoceros Diceros bicornis minor and white rhinoceros Ceratotherium simum simum in Ndumu Game Reserve by repeated sightings of known individuals and groups. The black rhino population in June 1986 was estimated to be 42, of which 10% were juveniles and with an adult sex ratio not differing significantly from parity. Their home range varied between 4·3 km 2 for a mixed group of animals and 13·8 km 2 for an adult female with calf. Home range overlap varied from 12 to 80%. The white rhinoceros population in June 1986 was estimated to consist of 57 animals of which 14% were juveniles. Adult sex ratio did not differ significantly from parity. Home range size varied from 2·5 to 22·9 km 2 and overlapped extensively for both sexes. Both populations of rhino in Ndumu are below the proposed minimum effective population size of 50. Consequently, for both species we recommend that in conjunction with the sustained removal of animals from the population, individuals from the parent populations should be periodically introduced into the reserve to increase the effective population size.