Current staff members of the MRI are listed below in alphabetical order. Please click on the "More details" button to view additional information for a particular staff member e.g. recent publications.
Dr. Fredrik Dalerum
Postdoctoral Research Fellow Causes and consequences of resource specialization in mammals
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Biodiversity effects of large carnivores fredrik.dalerum@zoology.up.ac.za +27-12-4204618
Research project summmary Causes and consequences of resource specialization in mammals Biodiversity effects of large carnivores Students currently under co-supervision MSc (research) Mr. Low de Vries Effects of resource abundance on the diet and home range size of the bat-eared fox (Otocyon megalotis ) Ms. Sonja Streicher Patterns of body temperature in free living Cryptomys damarensis
Non-departmental students under supervision BSc (Hons) Ms. Lisa Isaacs (Centre for Wildlife Management, University of Pretoria ) Ms. Cher Lawrence (Centre for Wildlife Management, University of Pretoria ) Ms. Meike Meijers (University of Utrecht ) Mr. Chrispijn Schilp (University of Utrecht ) MSc (research) Ms. Janelle Bashant (Centre for Wildlife Management, University of Pretoria ) PhD Mr. Lourens Swanepoel (Centre for Wildlife Management, University of Pretoria ) Recent Publications 2009 Dalerum, F., Kunkel, K., Angerbjorn, A., Shults, B. (2009) Patterns of d13C and d15N in wolverine (Gulo gulo) tissues from the Brooks Range, Alaska. Current Zoology. 55 :188-192Cameron, E.Z., Dalerum, F. (2009) Trivers-Willard effect in contemporary humans: male biased sex ratios among billionaires. PLoS One. 4(1) :-Dalerum, F., Kunkel, K., Angerbjorn, A., Shults, B. (2009) Diet of wolverines in the western Brooks Range, Alaska. Polar Research. 28 :246-253Dalerum, F., Cameron, E.Z., Somers, M.J., Kunkel, K. (2009) Continental patterns of carnivore guild depletions: Implications for prioritizing global carnivore conservation. Biology Letters. 5 :35-382008 Dalerum, F., Lange, H., Skarpe, C., Rooke, T., Inga, B., Bateman, P.W. (2008) Group size, antipredatory vigilance and foraging competition in two species of gregarious antelope. South African Journal of Wildlife Research. 38 :138-145Belton, L., Dalerum, F., van Rensburg, B.J. (2008) Factors associated with suni distribution in Tembe Elephant Park, South Africa: implications for management and conservation of a small antelope. African Journal of Ecology. 46 :631-636Dalerum, F., Somers, M.J., Cameron, E.Z., Kunkel, K. (2008) The potential for large carnivores to act as biodiversity surrogates southern Africa. Biodiversity and Conservation. 17 :2939-2949Dalerum, F., Shults, B., Kunkel, K. (2008) Estimating sustainable harvest in wolverine populations using logistic regression. Journal of Wildlife Management. 72 :1125-11322007 Dalerum, F., Boutin, S., Dunford, J. (2007) Wildfire effects on home range size and fidelity of boreal caribou in Alberta, Canada. Canadian Journal of Zoology. 85 :26-32Dalerum, F., Loxterman, J., Shults, B., Kunkel, K., Cook, L. (2007) Sex-specific dispersal patterns in wolverines; Insights from microsatellite markers`. Journal of Mammalogy. 88 :793-800Dalerum, F. (2007) Phylogenetic reconstruction of carnivore social organisations. Journal of Zoology. 273 :90-97Dalerum, F., Bennett, N.C., Clutton-Brock, T.H. (2007) Longitudinal differences in 15N between mothers and offspring during and after weaning in a small cooperative mammal, the meerkat (Suricata suricatta ). Rapid Communications in Mass Spectrometry. 21 :1889-18922006 Dunford, J.S., McLoughlin, P.D., Dalerum, F., Boutin, S. (2006) Lichen abundance in the peatlands of northern Alberta: implications for boreal caribou. Ecoscience. 13 :469-474Dalerum, F., Creel, S., Hall, S. (2006) Behavioral and endocrine correlates of reproductive failure in captive wolverines. Journal of Zoology. 269 :527-5372005 Dalerum, F., Angerbjorn, A. (2005) Resolving temporal variation in vertebrate diets using naturally occurring stable isotopes. Oecologia. 144 :647-658Dalerum, F., Shults, B., Kunkel, K. (2005) A serologic survey for antibodies to three canine viruses in wolverines (Gulo gulo) from the Brooks Range, Alaska. Journal of Wildlife Diseases. 41 :792-7952003 Olsson, G., Dalerum, F., Hornfeldt, B., Ahlm, C., Juto, P. (2003) Human hantavirus infections, Sweden. Emerging Infectious Diseases. 9 :1395-14012002 Dalerum, F., Tanerfeldt, M., Elmhagen, B., Becker, D., Angerbjorn, A. (2002) Distribution, morphology and use of arctic fox dens in Sweden. Wildlife Biology. 8 :187-194Russell, A.F., Clutton-Brock, T.H., Brotherton, P.N.M., Sharpe, L., McIlrath, G.M., Dalerum, F., Cameron, E.Z., Barnard, J. (2002) Factors affecting pup growth and survival in cooperatively breeding meerkats Suricata suricatta. . Journal of Animal Ecology. 71 :700-7092000 Dalerum, F., Angerbjorn, A. (2000) Diet of the arctic fox (Alopex lagopus) in Karupelv valley, North East Greenland, during a summer with low lemming density. Arctic. 53 :1-8Website Links of Importance Centre for Wildlife Management IBREAM
Dr. Simon Elwen
Marine mammal ecology Ecology of Heaviside's dolphins simon.elwen@gmail.com +27-12-4202067
Research project summmary Simon\\\'s post-doctoral work primarily involves the preparation for publication of his PhD work on the ecology of Heaviside\\\'s dolphins in the western Cape.
PhD work: The distribution, movements and abundance of Heaviside’s dolphins in the nearshore waters of the Western Cape, South Africa
Heaviside\\\'s dolphin (Cephalorhynchus heavisidii) is a poorly studied coastal delphinid with a limited inshore distribution off the west coast of southern Africa where it is sympatric with the similar sized dusky dolphin (Lagenorhynchus obscurus). It is exposed to an unknown level of bycatch particularly in near-shore set-net fisheries and is also potentially impacted by the growing boat-based whale watching industry in South Africa. In my thesis I describe the results of a study investigating the distribution, movements, behaviour and abundance of Heaviside\\\'s dolphins in the near-shore environment of the Western Cape of South Africa as a precursor to assessing its potential vulnerability to anthropogenic threats. Data were gathered using three different approaches in the field; diurnal shore based observations, boat based photo-ID surveys along ~390 km of coastline and satellite telemetry. Data were collected for dusky dolphins where feasible.
Students currently under co-supervision BSc (Hons) Lauren Snyman MSc (research) Ms. Edith Mertz Investigation of the diurnal movements, behaviour and habitat use of coastal cetaceans in Mossel Bay: top predator sympatry and anthropogenic impacts. Recent Publications 2009 Heinrich, S., Elwen, S.H., Brager, S. (2009) Patterns of Sympatry in Lagenorhynchus and Cephalorhynchus: Dolphins in Different Habitats. Elwen, S.H., Best, P.B., Reeb, D., Thornton, M. (2009) Diurnal movements and behaviour of Heaviside’s dolphins, Cephalorhynchus heavisidii , with some comparative data for dusky dolphins, Lagenorhynchus obscurus . South African Journal of Wildlife Research. 39(2) :100-102Elwen, S., Reeb, D., Thornton, M., Best, P.B. (2009) A population estimate of Heaviside’s dolphins, Cephalorhynchus heavisidii , at the southern end of their range. Marine Mammal Science. 25(1) :107-1242006 Elwen, S.H., Meyer, M.A.M., Best, P.B., Kotze, P.G.H., Thornton, M., Swanson, S. (2006) Range and movements of a nearshore delphinid, Heaviside's dolphin Cephalorhynchus heavisidii a determined from satellite telemetry. Journal of Mammalogy. 87(5) :866-8772004 Elwen, S.H., Best, P.B. (2004) Are there reproductive benefits to southern right whale females (Eubalaena australis) associated with their coastal distribution off South Africa? Marine Ecology Progress Series . 269 :289-295Elwen, S.H., Best, P.B. (2004) Environmental factors influencing the distribution of southern right whales (Eubalaena australis) on the south coast of South Africa I: Broad scale patterns. Marine Mammal Science . 20(3) :567-582Elwen, S.H., Best, P.B. (2004) Environmental factors influencing the distribution of southern right whales (Eubalaena australis) on the south coast of South Africa II: Within bay distribution. Marine Mammal Science . 20(3) :583-601Website Links of Importance simonelwen.net
Dr. Sarita Maree
1. The conservation of golden moles (Afrosoricida; Chrysochloridae) in South Africa smaree@zoology.up.ac.za +27-12-4203871
Research project summmary My main research interests reside in the fields of molecular systematics, phylogeography conservation and population genetics. Current research primarily focuses on golden moles (Chrysochloridae), an ancient group that resorts under Africa’s most threatened small mammals, and one of only two families of subterranean mammals endemic to the continent. Two thirds of all currently recognized golden mole species are listed in the IUCN Species Survival Commission’s Afrotheria Specialist Group assessment 2007. Golden moles tend to be restricted-range taxa, which make them vulnerable to habitat degradation and local extinction, and most of the recognized species, are only known from scattered, isolated populations. Nonetheless, the habitat of many threatened species such as Juliana’s golden mole, are being ruthlessly destroyed by human activity (urbanization, agriculture and mining). The future of golden moles is largely dependent on the concerted efforts of conservationists, developers, farmers and the public to nurture the unique habitats suitable for their survival. Superficially, many of the 21 recognised species appear identical, but it is possible that several “hidden” (cryptic) species may still be described from within the current species pool. Given that a sound taxonomic classification and an adequate understanding of the population genetics at both a regional and localized scale is fundamental for making informed management decisions relevant to the conservation of taxa,
Recent Publications 2009 Bastos, A.D.S., Arnot, L.F., Jacquier, M.D., Maree, S. (2009) A host species-informative internal control for molecular assessment of African swine fever virus infection rates in the African sylvatic cycle Ornithodoros vector. Medical and Veterinary Entomology. 23 (4) :399-409Taylor, P.J., Maree, S., van Sandwyk, J., Kerbis Peterhans, J.C., Stanley, W.T., Verheyen, E., Kaliba, P., Verheyen, W., Kaleme, P., Bennett, N.C. (2009) Speciation mirrors geomorphology and palaecclimatic history in African laminate-toothed rats (Muridae; Otomyini) of the Otomys denti and O. lacustris species-complexes in the. Biological Journal of the Linnean Society. 96 :913-941
Dr. Tadamichi Morisaka Dr. M Oosthuizen
Factors influencing neurogenesis and memory in three mole-rat species exhibiting a wide spectrum of social organisation. moosthuizen@zoology.up.ac.za +27-12-4202539
Research project summmary Both solitary and social mole-rat species will be evaluated for circadian rhythmicity. The results will be used to assess whether circadian rhythmicity has an effect on memory. Individuals that show robust locomotor activity rhythms may be more prone to explore than ‘lazy’ animals that display a low level of activity.
Mole-rats will be used in a memory activity experiment assessing performance of animals in a maze. This experiment will enable us to determine whether sociality has an impact on memory. Solitary species typically have very simple burrow structures, while social species dig very complicated burrow systems. Also in social species, a number of individuals work simultaneously at extending the tunnel systems, hence it would require the colony members to memorize new tunnels rapidly for easy movement in the tunnel system. Thus it is hypothesised that social species would have a better success rate in a maze than solitary species.
On completion of behavioural experiments, animals will be sacrificed to stain immunohistochemically for neurogenesis in the brain. This will elucidate whether there is a relationship between social status and neurogenesis. It is well known that gonadal hormones promotes neurogenesis and enhances new cell survival in adults, thus it would be interesting to compare physiologically suppressed, subordinate females and the dominant Damaraland females with the behaviourally suppressed subordinate Natal mole-rat females and their dominants where gonadal inhibition does not occur. Theoretically, in animals where gonadal steroid hormone levels are suppressed, neurogenesis should also be suppressed.
Also the size of the hippocampus of solitary and social species will be measured to determine whether there are any differences between the different species. Given that social species have a higher demand to memorise more complex tunnel systems, it is hypothesised that their hippocampuses should be larger than the solitary species’ with less complex tunnel systems.
Recent Publications 2010 Young, A.J., Oosthuizen, M.K., Lutermann, H., Bennett, N.C. (2010) Physiological suppression eases in Damaraland mole-rat societies when ecological constraints on dispersal are relaxed. Hormones and Behavior. 57 :177-1832008 de Vries, L., Oosthuizen, M.K., Sichilima, A.M., Bennett, N.C. (2008) Circadian rhythms of locomotor activity in Ansell's mole-rat: are mole-rat's clocks ticking? Journal of Zoology. 276 :343-349Oosthuizen, M.K., Bennett, N.C., Coen, C.W. (2008) An immunohistochemical study of the gonadotrophin-releasing hormone 1 system in solitary Cape mole-rats, Georychus capensis, and social Natal mole-rats, Cryptomys hottentotus natalensis. Neuroscience. 157 :164-173Oosthuizen, M.K., Bennett, N.C., Lutermann, H., Coen, C.W. (2008) Reproductive suppression and the seasonality of reproduction in the social Natal mole-rat (Cryptomys hottentotus natalensis ). General and Comparative Endocrinology. 159 :236-240Download my complete publication record
Dr. Mai Sakai Dr. Alfred Sichilima
The burrow structure, colony composition and reproductive biology of the Fukomys anselli from the Lusaka province of Zambia. asichilima@zoology.up.ac.za +27-12-4204618
Research project summmary African mole-rats (Bathyergidae) provide an excellent model system with which to test theories relating to the evolution and maintenance of sociality in underground mammals. The range of habitats they occupy is variable and mainly dependent on the availability of the food resource in the form of geophytes. The Aridity Food Distribution Hypotheis has been put forward in attempt to explain why some mole-rats are strictly solitary and others exhibiting extreme sociality. In this scenario, sociality is adaptive as cooperative foraging spreads the energetic costs of burrowing and increases the chance of finding food items, which because of the clumped nature of the resource is sufficient once found to support larger groups of mole-rats. To quantify the burrow metrics in relation to seasonal energetic cost of foraging, cooperative foraging, colony size formation and the seasonal variation of quantities of food in burrows, fractal dimension analysis is undertaken on excavated burrow systems. However, to date, the above detailed studies have only been carried out on Giant mole-rat Fukomys mechowii .My current research focuses upon the burrow structure, colony composition and the reproductive biology of Ansell’s mole-rat Fukomys anselli (Bathyergidae) from the Lusaka Province of Zambia.
Recent Publications 2008 de Vries, L., Oosthuizen, M.K., Sichilima, A.M., Bennett, N.C. (2008) Circadian rhythms of locomotor activity in Ansell's mole-rat: are mole-rat's clocks ticking? Journal of Zoology. 276 :343-349Sichilima, A.M., Bennett, N.C., Faulkes, C.G., Le Comber, S.C. (2008) Evolution of African mole-rats sociality: burrow architecture, rainfall and foraging in colonies of the cooperatively breeding Fukomys mechowii . Journal of Zoology. 275 :276-282Download my complete publication record
Recent Presentations Here are my most recent presentations. Please feel free to download them. Should you have trouble opening any of them please contact me for assistance.
The burrow structure, colony composition and reproductive biology of the giant mole-rat (Fukomys mechowii) Peters 1881 from the Copperbelt of Zambia Curriculum Vitae Here is my
Curriculum Vitae . Please feel free to download it. Should you have trouble opening it please contact me for assistance.
Download my Curriculum Vitae
Dr. Victoria Tornero
