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Miller S.M.,Tshwane University of Technology | Miller S.M.,University of Pretoria | Harper C.K.,University of Pretoria | Bloomer P.,University of Pretoria | And 2 more authors.
PLoS ONE | Year: 2015

Population fragmentation is threatening biodiversity worldwide. Species that once roamed vast areas are increasingly being conserved in small, isolated areas. Modern management approaches must adapt to ensure the continued survival and conservation value of these populations. In South Africa, a managed metapopulation approach has been adopted for several large carnivore species, all protected in isolated, relatively small, reserves that are fenced. As far as possible these approaches are based on natural metapopulation structures. In this network, over the past 25 years, African lions (Panthera leo) were reintroduced into 44 fenced reserves with little attention given to maintaining genetic diversity. To examine the situation, we investigated the current genetic provenance and diversity of these lions. We found that overall genetic diversity was similar to that in a large national park, and included a mixture of four different southern African evolutionarily significant units (ESUs). This mixing of ESUs, while not ideal, provides a unique opportunity to study the impact of mixing ESUs over the long term. We propose a strategic managed metapopulation plan to ensure the maintenance of genetic diversity and improve the long-term conservation value of these lions. This managed metapopulation approach could be applied to other species under similar ecological constraints around the globe. © 2015 Miller et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Ferreira S.M.,Scientific Services | Hofmeyr M.,Veterinary Wildlife Services
South African Journal of Wildlife Research | Year: 2014

Large carnivores are key foci for conservationists, tour operators and hunters alike. They provide revenue-generating opportunities,but also canbekeystonespeciesinconservation areas, influencing the maintenance of biological diversity. They often degrade livelihoods of people when coming into conflict with livestock land-uses. We acknowledge these challenges specifically for cases where large carnivores are present in small areas and propose an alternative strategy to the traditional carrying capacity approaches, directed at managing theeffectsoflarge carnivores.Weadvocateanapproach where managersofsmall areas mimic natural socialdynamics suchascoalition tenure,density dependent changesin litter size,age at first birth and birth intervals,as well as subadult dispersal. This assists with achievement of population and evolutionary targets through a process-based approach mimicking drivers of variance in social groups. Such an applied conservation husbandry approach may have robust outcomes that do not compromise conservation values.

Miller S.M.,Tshwane University of Technology | Miller S.M.,University of Pretoria | Harper C.K.,University of Pretoria | Bloomer P.,University of Pretoria | And 2 more authors.
Journal of Heredity | Year: 2014

The South African lion (Panthera leo) population is highly fragmented. One-third of its wild lions occur in small (<1000 km2) reserves. These lions were reintroduced from other areas of the species' historical range. Management practices on these reserves have not prioritized genetic provenance or heterozygosity. These trends potentially constrain the conservation value of these lions. To ensure the best management and long-term survival of these subpopulations as a viable collective population, the provenance and current genetic diversity must be described. Concurrently, poaching of lions to supply a growing market for lion bones in Asia may become a serious conservation challenge in the future. Having a standardized, validated method for matching confiscated lion parts with carcasses will be a key tool in investigating these crimes. We evaluated 28 microsatellites in the African lion using samples from 18 small reserves and 1 captive facility in South Africa, two conservancies in Zimbabwe, and Kruger National and Kgalagadi Transfrontier Parks to determine the loci most suited for population management and forensic genetic applications. Twelve microsatellite loci with a match probability of 1.1×10-5 between siblings were identified for forensics. A further 10 could be added for population genetics studies. © 2014 The American Genetic Association. All rights reserved.

Hausler G.,Veterinary Wildlife Services | Slater K.,University of South Africa
Koedoe | Year: 2016

Mixed-species foraging flocks (MSFFs) of birds can be defined as aggregations of more than two species that actively initiate and continue their association while foraging, without being drawn to a single resource. MSFFs have been well documented for terrestrial habitats globally, but rarely in southern Africa. This study describes the composition of MSFFs in two habitat types (Acacia and Combretum) within the southern Kruger National Park, South Africa during the late dry season. Thirty-one MSFFs were recorded in each of the two habitat types, with 1251 individuals of 74 different species being observed. We found that compared to Combretum, (mean: 10.7 ± 5.2 s.d.) Acacia had significantly more individuals per MSFFs (mean: 21.5 ± 12.6 s.d.) and more species per MSFF (Acacia mean: 8.7 ± 3.5 s.d.; Combretum mean: 5.9 ± 1.7 s.d.). The mean number of individuals per species per 31 MSFFs was 9.3 (± 4.5 s.d.) and 7.6 (± 5.6 s.d.) in the Acacia and Combretum habitat types respectively. The most frequently occurring species in both habitat types was the Fork-tailed Drongo (Dicrurus adsimilis). There was a significant association between certain species pairs in both habitats. Future studies in this area could be done to investigate the reasons behind the differences in MSFF sizes and species numbers between habitats. The season during which this study was performed excluded all summer migrants and a similar investigation in the wet season may reveal a different MSFF composition. Conservation implications: Understanding the dynamics and compositions of MSFFs, could form a valuable component of avian biodiversity monitoring both in and outside of protected areas. Within a given area, changes in the composition and behaviour of MSFFs over time could potentially be used as early indicator of threats to biodiversity. © 2016. The Authors.

Miller M.,Stellenbosch University | Kruger M.,Veterinary Wildlife Services | Olea-Popelka F.,Colorado State University | Buss P.,Veterinary Wildlife Services
Journal of Wildlife Diseases | Year: 2016

Ninety-four subadult and adult white rhinoceroses (Ceratotherium simum) were captured between February and October, 2009–11, in Kruger National Park and placed in holding bomas prior to translocation to other locations within South Africa. A simple threecategory system was developed based on appetite, fecal consistency/volume, and behavior to assess adaptation to bomas. Individual animal and group daily median scores were used to determine trends and when rhinoceroses had successfully adapted to the boma. Seventeen rhinoceroses did not adapt to boma confinement, and 16 were released (1 mortality). No differences in boma scores were observed between rhinoceroses that adapted and those that did not, until day 8, when the first significant differences were observed (adapted score=13 versus nonadapted score=10). The time to reach a boma score determined as successful adaptation (median 19 d) matched subjective observations, which was approximately 3 wk for most rhinoceroses. Unsuccessful adaptation was indicated by an individual boma score of less than 15, typically during the first 2 wk, or a declining trend in scores within the first 7–14 d. This scoring system can be used for most locations and could also be easily adapted to other areas in which rhinoceroses are held in captivity. This tool also provides important information for assessing welfare in newly captured rhinoceroses. © Wildlife Disease Association 2016.

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