A5054818215- Wildlife Ecology and Conservation
- Ecology and Vegetation Dynamics Studies
- Species Distribution and Climate Change
- Animal Behavior and Welfare Studies
- Rangeland Management and Livestock Ecology
- Wildlife-Road Interactions and Conservation
- Zoonotic diseases and public health
- Ecology and biodiversity studies
- Genetic and phenotypic traits in livestock
- Animal Disease Management and Epidemiology
- Animal Ecology and Behavior Studies
- Bat Biology and Ecology Studies
- Rangeland and Wildlife Management
- Conservation, Biodiversity, and Resource Management
- Genetic diversity and population structure
- Forest Management and Policy
- Isotope Analysis in Ecology
- Avian ecology and behavior
- Human-Animal Interaction Studies
- Data Analysis with R
- Primate Behavior and Ecology
- Fish Ecology and Management Studies
- Polar Research and Ecology
- Identification and Quantification in Food
- Animal Diversity and Health Studies
South African National Parks
2015-2024
Scientific Services
2015-2024
Cape Peninsula University of Technology
2021-2024
North-West University
2023-2024
University of Pretoria
1999-2017
University of KwaZulu-Natal
2013-2015
University of Auckland
2005-2007
Mammal Research Institute
1996
African elephants ( Loxodonta africana ) are imperiled by poaching and habitat loss. Despite global attention to the plight of elephants, their population sizes trends uncertain or unknown over much Africa. To conserve this iconic species, conservationists need timely, accurate data on elephant populations. Here, we report results Great Elephant Census (GEC), first continent-wide, standardized survey savannah elephants. We also provide quantitative model across estimated a 352,271 study...
Conflict between people and elephants in Africa is widespread yet many solutions target the symptoms, rather than underlying causes, of this conflict. To manage conflict better causes problem need to be examined. Here we examine factors spatial use by along Okavango Panhandle Ngamiland, northern Botswana, provide ways address people. We found that (1) elephant was a function season, (2) did not differ breeding herds bull groups, (3) only overlapped significantly at night, during dry (4) crop...
Context. Lion (Panthera leo Linnaeus, 1758) populations experience a range of ecological and human influences that affect their demography. Few lion have reliable estimates population size, trends in these, or demographic profiles. Threats such as those imposed by diseases are thus hard to evaluate respond to. Aims. To calibrate call-up stations define survey effort required achieve with known precision, extract age structures estimate survival rates, numbers, sex structure then the effect...
Population size and trends of large carnivores are difficult to determine, but often needed inform conservation actions. Direct counts maintained over long time periods extremely achieve. Indices population sizes can be used estimate carnivore abundances, case-, species- site-specific. Here, we test the general applicability track-based indices abundance. We surveyed 15 306.4 km roads associated with 339 transects across a wide geographical scale, range densities variable substrates for...
The onslaught on the World's rhinoceroses continues despite numerous initiatives aimed at curbing it. When losses due to poaching exceed birth rates, declining rhino populations result. We used previously published estimates and growth rates for black rhinos (2008) white (2010) together with known trends time predict population sizes in Kruger National Park, South Africa 2013. is a stronghold south-eastern southern rhino. Counting 878 blocks 3x3 km size using helicopters, estimating...
The onslaught on the World's wildlife continues despite numerous initiatives aimed at curbing it. We build a model that integrates rhino horn trade with population dynamics in order to evaluate impact of various management policies sustainability. In our model, an agent-based sub-model from poaching event up through purchase Asia impacts abundance. A data-validated, individual-based South Africa provides these abundance values. consist different combinations legal initiatives, demand...
Abstract The rehabilitation program conducted by Richards Bay Minerals (RBM) of areas exposed to opencast surface mining sand dunes north (28°43'S, 32°12'E) on the coast northern KwaZulu‐Natal Province commenced 16 years before this study and has resulted in development a series known‐aged stands vegetation. By assuming that these spatially separated develop along similar pathway over time, instantaneous sampling should reveal successional or other changes usually associated with aging...
Do communities return to their former state when we disturb them? The answer is "surely not always," since some disturbances may be so devastating that recovery will impossible. If do recover, then how fast recovery? different subsets of species at the same rate? Is rate a simple exponential recovery— meaning change toward original fastest community furthest away and it slows as converges? Or more dynamically complex process? These questions are theoretically interesting practically...
Abstract The influence of elephants on woody vegetation cover varies from place to place. In part this may be due the way utilize space across landscapes and within their home ranges in response availability distribution food. We used location data 18 cows at six study sites an east west rainfall gradient southern Africa test whether wet‐ dry‐season home‐range sizes, evenness use seasonal range overlap between seasons years, differed wet dry savannas. then tested quantity, stability...
Managers of African lions (Panthera leo) on reserves where they have been reintroduced increasingly face challenges associated with ecological regulation,genetic degradation and increased susceptibility to catastrophic events. The Lion Management Forum (LiMF) was formed in 2010 define these explore possible solutions the view developing appropriate management guidelines. LiMF bases its recommendations ecologically sound premise that managers should, as far possible, mimic natural processes...
The considerable threats of invasive rodents to island biodiversity are likely be compounded by climate change. Forecasts for such interactions have been most pronounced the Southern Ocean islands where ameliorating conditions expected decrease thermal and resource restrictions on rodents. Firm evidence changing rodent populations in response change, demonstrations associated impacts terrestrial environment, nonetheless entirely absent region. Using data collected over three decades...
Unrelenting poaching to feed the illegal trafficking of rhinoceros (rhino) horn remains principle threat persistence south-central black and southern white rhino that live in Kruger National Park (Kruger), South Africa. Other global environmental change drivers, such as unpredictable climatic conditions, impose additional uncertainties on management these species. The drought experienced over 2015/2016 rainy season may have affected population growth thus added an pressure already occurring....
Abstract Background Fine-scale data on animal position are increasingly enabling us to understand the details of movement ecology and dead-reckoning, a technique integrating motion sensor-derived information heading speed, can be used reconstruct fine-scale paths at sub-second resolution, irrespective environment. On its own however, dead-reckoning process is prone cumulative errors, so that estimates quickly become uncoupled from true location. Periodic ground-truthing with aligned location...
Abstract Top predators such as crocodiles often reflect ecosystem degradation. The recent spate of close to 200 Nile crocodile deaths may the state Olifants–Letaba River system in Kruger National Park. This paper investigates whether were indeed consequence a rare and perhaps acute event given variability annual population growth rates crocodilians. Spotlight‐ helicopter‐based surveys designed correct for availability detectability bias used estimate sizes from 2008 2010 around Olifants...
White rhinoceros (rhinos) is a keystone conservation species and also provides revenue for protection agencies. Restoring or mimicking the outcomes of impeded ecological processes allows reconciliation biodiversity financial objectives. We evaluate consequences white rhino management removal, in recent times, poaching, on population persistence, regional opportunities generation. In Kruger National Park, rhinos increased from 1998 to 2008. Since then may vary non-directionally. 2010, we...
Wildlife trafficking, a focus of organized transnational crime syndicates, is threat to biodiversity. Such networks span beyond protected areas holding strongholds species interest such as African rhinos. extend over several countries and hence the jurisdiction any one law enforcement authority. We show how federated database can overcome disjoint information kept in different databases. also social network analyses provide enforcers with targeted responses that maximally disrupt criminal...
The Kruger National Park is a stronghold for African wild dog Lycaon pictus and cheetah Acinonyx jubatus conservation in South Africa. Tourist photographic surveys have been used to evaluate the minimum number of dogs cheetahs alive over last two decades. Photographic-based capture-recapture techniques open populations were on data collected during survey done 2008/9. Models run park as whole per region (northern, central, southern). A total 412 (329–495; SE 41.95) 151 (144–157; 3.21) occur...
Droughts are predicted to increase in frequency and intensity for large parts of Africa. It is unclear how this may impact native grazers protected areas, these outcomes differ under contrasting management approaches. Reducing artificial water sources increasing the size areas have been proposed as responses that could possibly system resilience buffer herbivores against large-scale mortality during droughts. Long-term spatially explicit buffalo, elephant hippo census data from Kruger...
Abstract Understanding the population dynamics of savanna elephants depends on estimating parameters such as age at first reproduction, calving interval and age‐specific survival rates. The generation these parameters, however, relies ability to accurately determine individuals, but a reliable estimation technique for free‐ranging is presently not available. Shoulder heights were measured in 10 populations five countries across southern eastern Africa. Data included shoulder height...
Small population sizes provide several challenges to conservation managers seeking ensure species persistence and illustrating success. Black rhinoceros, Diceros bicornis minor, epitomizes these challenges. During October 2008 we used block surveys, estimates of availability observer bias calculate landscape-specific black rhino abundances in the southern parts Kruger National Park, South Africa. We assigned age sex individuals, extracted an distribution, estimated survival fecundity given...
The concept of thresholds potential concern (TPCs) as implemented for the last decade in strategic adaptive management South African National Parks (SANParks), has proved workable practice a number instances, but others appears beset by conceptual and practical limitations or barriers. Three common challenges relate to (1) situations where there is uncertainty about whether real exist, (2) how preferences other social constructs, opposed what were seen objective biophysical variables only,...