Rhinoceros populations in Africa are under severe threat as a result of surging poaching rates and risk-mitigation strategies are continuously adapted in an attempt to ensure the survival of the species. This study compares faecal glucocorticoid metabolite (fGCM) levels of two age classes of limited free-ranging female white rhinos with fGCM levels of adult free-ranging female white rhinos. Subsequently, fGCM alterations in the limited free-ranging animals were monitored following routine dehorning as a measure of the animals' short-term physiological stress response.Baseline fGCM levels differed significantly between tested groups, with both freeranging and limited free-ranging adult animals showing significantly higher fGCM levels compared to limited-free ranging juvenile females. In contrast, baseline fGCM levels did not differ significantly between limited free-ranging and free-ranging adult individuals. Routine dehorning procedures resulted in a short-term stress response expressed by a significant increase in fGCM levels 48 h post-dehorning, with stress steroid levels returning to pre-dehorning concentrations 72 h after the procedure.

The population of free-roaming white rhinoceroses (Ceratotherium simum) is under serious threat. Captive breeding of this species is therefore becoming more important, but this is challenging and often not successful. Obtaining reproductive reference values is a crucial aspect of improving these breeding results. In this study performed between 2008 and 2016, reproductive performance was analysed in 1,354 animals kept in a 8000 hectares game-ranched environment. Descriptive statistics of this captive population showed an average annual herd growth (%) of 7 .0±0.1 (min -9 –max 15). Average calving rates were calculated as an annual calving rate of 20% and biennial calving rate of 37% adult females calving per year. Females had a median age of 83.2 months at first calving (IQR 72.9–110.7) and inter-calving intervals of 29.2 (IQR 24.6–34.8) months. Furthermore, translocations of animals did not interfere with reproductive success in terms of inter-calving periods or age at first calving. Multivariate models showed a clear seasonal calving pattern with a significant increase of the number of calvings during December–April when compared to April–December. Our results did not show any significant skewed progeny sex ratios. Weather observations showed no significant influence of rain or season on sex ratios of the calves.

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The southern white rhinoceros (SWR) Ceratotherium simum simum, like all extant rhinoceros' species, is under global threat of extinction, due to their dwindling wild population numbers in protected areas and state-owned parks as a result of poaching. The Kruger National Park (KNP), the renowned state-owned stronghold for SWR, has suffered an estimated decline of over 75.0% of its population since 2011, with the highest annual poaching rates over the past decade and a remaining population estimated at only 2,607 animals by the end of 2020, which is an average annual population decline of -10.2% from 2008 to 2020, and 2,458 animals left by the end of June 2022. On the contrary, SWR under private custodianship and management on rewilded agro-sustainable biodiversity game ranches in South Africa (estimated currently at >8,000 animals, some of which are registered Captive Breeding Operations [CBO]; assessed CBOs contained 2,882 rhinos at the time of this study (Sep 2021), have increased in population numbers and survival rates, sustaining average annual population growth performances of 9.0%. This increase has been attributed to effective security, provision of additional habitat, dispersal, and frequent genetic exchange of rhinos between breeding subpopulations by the private sector. The conservation success of the private sector has largely been overlooked and disregarded by world conservation bodies and organizations, mostly due to misguided and prejudiced media publicity and the lack of scientific analytical assessment. Private rhino custodians and their biological/conservation breeding practices, with private agro-sustainable biodiversity wildlife management and/or captive breeding, generally being perceived and branded as either "canned" or equated to "captive zoological-gardens". Since the commencement of the International Convention on Biodiversity, global controversy exists whereby most of mankind today perceive bio-conservation of a species to be assigned in principle solely to protected areas and state-owned parks. The unique and advantageous roles of rewilded bio-conservation and sustainable-use conservation CBOs, being a key to green-economy and natural capital in a post-Covid-19 struggle, are mostly ignored. This study serves to assess and quantify the impact of private wildlife ranching in South Africa with specific focus on its potential contribution to rhino conservation specifically for that of the SWR C.s. simum.