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Drowning in data, thirsty for information and starved for understanding: A biodiversity information hub for cooperative environmental monitoring in South Africa

- MacFadyen, Sandra, Allsopp, Nicky, Altwegg, Res, Archibald, Sally, Botha, Judith, Bradshaw, Karen L, Carruthers, Jane, De Klerk, Helen, de Vos, Alta, Distiller, Greg, Foord, Stefan, Freitag-Ronaldson, Stefanie, Gibbs, Richard, Hamer, Michelle, Landi, Pietro, MacFayden, Duncan, Manuel, Jeffrey, Midgley, Guy, Moncrieff, Glenn, Munch, Zahn, Mutanga, Onisimo, Sershen, Nenguda, Rendani, Ngwenya, Mzabalazo, Parker, Daniel M, Peel, Mike, Power, John, Pretorius, Joachim, Ramdhani, Syd, Robertson, Mark P, Rushworth, Ian, Skowno, Andrew, Slingsby, Jasper, Turner, Andrew, Visser, Vernon, van Wageningen, Gerhard, Hui, Cang

Hybrid approaches to teaching: Re-imagining the teaching of a foundational science course during a global pandemic

- Parker, Daniel M, Vorster, Jo-Anne E, Quinn, Lynn, Blackie, Margaret A L

  • Authors: Parker, Daniel M , Vorster, Jo-Anne E , Quinn, Lynn , Blackie, Margaret A L
  • Date: 2022
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/426662 , vital:72377 , xlink:href="https://www.ajol.info/index.php/cristal/article/view/240803"
  • Description: Access to scientific knowledge, and teaching in the sciences, is believed to be about training because scientific knowledge is, generally, specialised. However, for students to gain full epistemological access in the sciences, they also need to be inducted as scientists and learners of science. We use Bernstein’s regulative and instructional discourse to engage with the notion of epistemological access and effectiveness of a foundational science course. We examine how the course can cultivate scientific identities amongst first year students at a recently established South African university. Our analysis assesses the impact of the forced shift from contact teaching to Emergency Remote Teaching due to the COVID-19 pandemic. We demonstrate that the course was able to begin to facilitate the cultivation of different kinds of knowers in science. However, several gaps remain. Thus, we argue that foundational science lecturers should focus on hybrid teaching approaches to promote enhanced learning amongst students.
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  • Date Issued: 2022

A leopard's favourite spots: habitat preference and population density of leopards in a semi-arid biodiversity hotspot

- Mann, Gareth K H, O'Riain, M Justin, Parker, Daniel M

  • Authors: Mann, Gareth K H , O'Riain, M Justin , Parker, Daniel M
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/148584 , vital:38752 , https://doi.org/10.1016/j.jaridenv.2020.104218
  • Description: Leopards (Panthera pardus) are the only free-ranging large predators to still occur naturally throughout much of Africa, but are vulnerable to habitat loss, ecosystem degradation and persecution. We used a systematic camera trap survey covering an area of ∼3100 km2 in the Little Karoo, a semi-arid biodiversity hotspot in South Africa, to assess the impacts of land use and habitat type on leopard density. Camera data were supplemented by opportunistic scat collection to produce a habitat suitability model. We used a habitat suitability model to inform spatially explicit capture-recapture models used to estimate population density. We recorded 152 independent photographs of 27 individually recognizable leopards at 54 camera stations and collected scats from a further 76 locations. Our habitat suitability model showed that primary productivity and vegetation type were the best predictors of leopard habitat suitability. Our best performing population density model allowed for detection and movement of individuals to vary according to sex, and estimated population density at 1.26 (SE ± 0.25) leopards/100 km2.
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  • Date Issued: 2020

Bat species richness and community composition along a mega-transect in the Okavango river basin:

- Weier, Sina M, Keith, Mark, Neef, Götz G, Parker, Daniel M, Taylor, Peter J

  • Authors: Weier, Sina M , Keith, Mark , Neef, Götz G , Parker, Daniel M , Taylor, Peter J
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149264 , vital:38820 , https://doi.org/10.3390/d12050188
  • Description: The Okavango River Basin is a hotspot of bat diversity that requires urgent and adequate protection. To advise future conservation strategies, we investigated the relative importance of a range of potential environmental drivers of bat species richness and functional community composition in the Okavango River Basin. During annual canoe transects along the major rivers, originating in the central Angolan highlands, we recorded more than 25,000 bat echolocation calls from 2015 to 2018. We corrected for possible biases in sampling design and effort.
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  • Date Issued: 2020

Do spotted hyaenas outcompete the big cats in a small, enclosed system in South Africa?:

- Comley, J, Joubert, C J, Mgqatsa, Nokubonga, Parker, Daniel M

  • Authors: Comley, J , Joubert, C J , Mgqatsa, Nokubonga , Parker, Daniel M
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/150099 , vital:38940 , doi:10.1111/jzo.12772
  • Description: Carnivores are adapted to kill, meaning sympatric carnivores can have particularly aggressive and harmful competitive interactions. The co‐existence of multiple carnivores in an ecosystem could be restricted by their similarity in ecological niches (e.g. dietary overlap); however, high prey abundances could facilitate their co‐existence. Although the development of small, enclosed reserves (over 400 km2) in South Africa has reduced human–carnivore conflict, these systems may increase the likelihood of carnivore intra‐guild competition due to the clumping of competing carnivores into these restricted spaces. Using carnivore scat and kill site analyses, we determined the dietary preferences and overlap of sympatric large carnivores in a small, enclosed reserve, Selati Game Reserve (Selati).
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  • Date Issued: 2020

Lions do not change rivers: complex African savannas preclude top-down forcing by large carnivores

- Comley, Jessica, Joubert, Christoffel J, Mgqatsa, Nokubonga, Parker, Daniel M

  • Authors: Comley, Jessica , Joubert, Christoffel J , Mgqatsa, Nokubonga , Parker, Daniel M
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149215 , vital:38816 , https://doi.org/10.1016/j.jnc.2020.125844
  • Description: Trophic cascade theories such as the ‘behaviourally-mediated trophic cascade hypothesis’ (BMTCH), have mainstreamed as ecological tools for conserving biodiversity and restoring ecosystems. The BMTCH relies on indirect negative effects of large carnivores through suppression of mesocarnivore activity and habitat use. Importantly, effects of top carnivores on mesocarnivores varies over time and space, is dependent on the species involved, and local context. In South Africa, there are very few free-ranging carnivores, as populations are often restricted to enclosed reserves. While predator-proof fences reduce human-wildlife conflict, they also influence space use within communities. We used an enclosed reserve with a relatively full complement of carnivores to test the generality of the BMTCH in the African context. Using single-species, multi-season occupancy models we investigated the spatial dynamics of multiple carnivores. We also investigated spatial partitioning by vegetation type and temporal partitioning.
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  • Date Issued: 2020

A novel technique for artificial pack formation in African wild dogs using odour familiarity:

- Marneweck, Courtney J, Marchal, Antoine F J, Marneweck, David G, Beverley, Grant, Davies-Mostert, Harriet T, Parker, Daniel M

  • Authors: Marneweck, Courtney J , Marchal, Antoine F J , Marneweck, David G , Beverley, Grant , Davies-Mostert, Harriet T , Parker, Daniel M
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/150060 , vital:38935 , https://doi.org/10.3957/056.049.0116
  • Description: Reintroductions are recognized tools for species recovery. However, operations are costly, difficult to implement, and failures are common and not always understood. Their success for group-living species depends on the mimicry of natural processes that promote social integration. Due to fragmented landscapes, human mediated (i.e. artificial) group formation is often required.
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  • Date Issued: 2019

Factors influencing the spatial patterns of vertebrate roadkill in South Africa: The Greater Mapungubwe Transfrontier Conservation Area as a case study

- Collinson, Wendy J, Parker, Daniel M, Bernard, Ric T F, Reilly, Brian K, Davies-Mostert, Harriet T

  • Authors: Collinson, Wendy J , Parker, Daniel M , Bernard, Ric T F , Reilly, Brian K , Davies-Mostert, Harriet T
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/158320 , vital:40172 , https://0-doi.org.wam.seals.ac.za/10.1111/aje.12628
  • Description: Few studies have investigated the factors that influence roadkill occurrence in developing countries. In 2013, we monitored a 100‐km section of the road (comprising the R572 and R521 regional highways and the D2662) that pass through the Greater Mapungubwe Transfrontier Conservation Area in South Africa, to assess the possible factors influencing roadkill. Over a period of 120 days, and across the three ecological seasons, we recorded 981 roadkills (rate = 0.08 roadkill/km/day) from four vertebrate taxonomic groups. We generated predictive models of roadkill from one combined data set that considered eight variables identified from the literature as potential correlates of roadkill. The model that included the distance of the fence from the road, habitat type adjacent to the road, and the presence of a hill in the road (i.e., elevation) or a bank on the side of the road best explained roadkill occurrence.
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  • Date Issued: 2019

The elephant in the ‘room’: determinants of songbird assemblages in the Thicket Biome, South Africa

- Parker, Daniel M

  • Authors: Parker, Daniel M
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/105134 , vital:32468 , https://doi.org/10.1080/01584197.2018.1562847
  • Description: When vegetation structure is altered, songbird communities may be affected. Despite speculation that African Elephant (Loxodonta africana) browsing impacts bird communities, existing data are limited. I sampled the bird communities of the Albany Thicket Biome at 10 sites in the Eastern Cape, South Africa, half with elephants and half without. Songbird community parameters were best predicted by how long elephants had been present, elephant density and the percentage cover of thicket vegetation. The sites where elephants had been present for longer had more bird species and increased songbird density and diversity. However, bird density also increased with increasing thicket vegetation cover and this is a phenomenon unlikely to be compatible with long-term elephant presence. There was an almost equal split between the number of bird species that appeared to be negatively affected by changes in habitat structure (47%) and those which benefited (53%). Smaller birds were generally more abundant as vegetation structural integrity increased and larger birds were more abundant when vegetation structural integrity declined. The browsing of elephants could be viewed as facilitative for songbirds in the short term. However, this effect may not persist in the long term because all elephant populations (notorious tree-fellers) in the Eastern Cape are found in fenced areas where natural migration is not possible. More broadly, my data provide important insight into how avian communities respond to habitat transformation at the local and regional scales.
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  • Date Issued: 2019

Using camera traps to generate a species inventory for medium-sized and large mammals in South West Zimbabwe:

- Welch, Rebecca J, Grant, Tanith, Parker, Daniel M

  • Authors: Welch, Rebecca J , Grant, Tanith , Parker, Daniel M
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/150267 , vital:38955 , https://0-doi.org.wam.seals.ac.za/10.3957/056.049.0089
  • Description: We investigated the presence of medium-sized and large mammals utilizing by-catch data from a camera trapping survey in the Mangwe District in South West Zimbabwe, an unprotected commercial livestock farming area which is impacted by human encroachment, poaching and trophy hunting. The camera trapping survey was carried out from 23 October to 5 December 2009, covered an area of 200 km2 and was initially intended to estimate the population density of leopards (Panthera pardus). The study area was split into two contiguous subsections, with each section sampled for a total of 20 days using 20 cameras. Camera trap photographs were identified to species level, then compared to a list of species thought to occur in the area according to available literature, as well as sightings from professional hunters and local landowners.
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  • Date Issued: 2019

Extended and Continuous Decline in Effective Population Size Results in Low Genomic Diversity in the World’s Rarest Hyena Species, the Brown Hyena

- Westbury, Michael V, Hartmann, Stefanie, Barlow, Axel, Wiesel, Ingrid, Leo, Viyanna, Welch, Rebecca J, Parker, Daniel M, Sicks, Florian, Ludwig, Arne, Dalén, Love, Hofreiter, Michael

  • Authors: Westbury, Michael V , Hartmann, Stefanie , Barlow, Axel , Wiesel, Ingrid , Leo, Viyanna , Welch, Rebecca J , Parker, Daniel M , Sicks, Florian , Ludwig, Arne , Dalén, Love , Hofreiter, Michael
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124482 , vital:35616 , https://doi.org/10.1093/molbev/msy037
  • Description: Hyenas (family Hyaenidae), as the sister group to cats (family Felidae), represent a deeply diverging branch within the cat-like carnivores (Feliformia). With an estimated population size of < 10,000 individuals worldwide, the brown hyena (Parahyaena brunnea) represents the rarest of the four extant hyena species and has been listed as Near Threatened by the IUCN. Here, we report a high-coverage genome from a captive bred brown hyena and both mitochondrial and low coverage nuclear genomes of 14 wild-caught brown hyena individuals from across southern Africa.We find that brown hyena harbor extremely low genetic diversity on both the mitochondrial and nuclear level, most likely resulting from a continuous and ongoing decline in effective population size that started_1Ma and dramatically accelerated towards the end of the Pleistocene. Despite the strikingly low genetic diversity, we find no evidence of inbreeding within the captive bred individual and reveal phylogeographic structure, suggesting the existence of several potential subpopulations within the species.
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  • Date Issued: 2018

A record of cheetah (Acinonyx jubatus) diet in the Northern Tuli Game Reserve, Botswana

- Craig, Christie A, Brassine, Eleanor I, Parker, Daniel M

  • Authors: Craig, Christie A , Brassine, Eleanor I , Parker, Daniel M
  • Date: 2017
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/123004 , vital:35395 , https://doi.org/10.1111/aje.12374
  • Description: Cheetahs (Acinonyx jubatus) typically prey upon the most available small to medium-sized (23–56 kg) antelope (Hayward et al., 2006). In Botswana, impala (Aepyceros melampus) and springbok (Antidorcas marsupialis), followed by steenbok (Raphicerus campestris) and duiker (Sylvicapra grimmia), are the prey species most frequently killed by cheetahs (Klein, 2007). Juvenile eland (Tragelaphus oryx), gemsbok (Oryx gazella), hartebeest (Alcelaphus buselaphus) and kudu (Tragelaphus strepsiceros) are also taken (Klein, 2007). The Northern Tuli Game Reserve (NOTUGRE) in eastern Botswana is naturally delineated by the nonperennial Shashe and Limpopo rivers in the east and south and has relatively porous game fencing along portions of the western and southern boundaries (Fig. 1) (Jackson, McNutt & Apps, 2012). Neither the fences nor the rivers restrict the movement of large carnivores such as cheetahs, lions (Panthera leo), leopards (Panthera pardus), spotted hyaenas (Crocuta crocuta) and African wild dogs (Lycaon pictus) onto neighbouring pastoral land (Jackson, McNutt & Apps, 2012). It is thus possible that cheetahs are feeding on livestock outside of the park. However, the diet of the cheetahs in NOTUGRE has not been evaluated. Our study serves to describe the diet of the cheetahs in NOTUGRE using both scats and kill sightings.
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  • Date Issued: 2017

Depth and habitat determine assemblage structure of South Africa’s warm-temperate reef fish

- Heyns-Veale, Elodie R, Bernard, Anthony T F, Richoux, Nicole B, Parker, Daniel M, Langlois, T J, Harvey, E S, Götz, Albrecht

  • Authors: Heyns-Veale, Elodie R , Bernard, Anthony T F , Richoux, Nicole B , Parker, Daniel M , Langlois, T J , Harvey, E S , Götz, Albrecht
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/456035 , vital:75477 , xlink:href="https://doi.org/10.1007/s00227-016-2933-8"
  • Description: Depth and habitat are important predictors of fish assemblage structure, yet current no-take marine protected area (MPA) networks are generally limited to providing refuge for fish species that inhabit shallow waters and may exclude deep habitats essential to exploited populations. To ensure MPA efficacy at the design, uptake and management levels, baseline data on fish populations associated with deep nearshore reefs are needed. This study employed baited remote underwater stereo-video systems to investigate fish habitat associations at shallow (11–25 m) and deep (45–75 m) reef sites in the Tsitsikamma National Park MPA, South Africa. The compositions of fish assemblages at shallow and deep reef sites were significantly different. Specifically, rare species, juveniles and low trophic level species dominated the shallow reef, while deep reef assemblages were characterised by large, sexually mature and predatory fish. The body size of abundant species was also correlated with depth, with larger individuals being more abundant on deeper reefs. Habitat types were identified according to a habitat classification system established in a previous study, which resulted in four broad depth separated habitat types (defined by macrobenthos and environmental variables). Canonical analysis of principle coordinates (CAP) indicated that habitat type was a good categorical predictor of the observed fish assemblages. The CAP analysis determined that 86 % of the samples were correctly assigned to the habitat type from which they were collected, indicating that specific fish assemblages were associated with distinct habitat types. This study highlights the importance of protecting both shallow and deep reefs, not only to ensure the conservation of particular fish assemblages, but also to provide protection for all stages of the life cycle of fish species.
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  • Date Issued: 2016

The influence of photoperiod on the reproductive physiology of the greater red musk shrew: Crocidura flavescens

- Hoole, C, McKechnie, Andrew E, Parker, Daniel M, Bennett, Nigel C

  • Authors: Hoole, C , McKechnie, Andrew E , Parker, Daniel M , Bennett, Nigel C
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/70136 , vital:29624 , https://doi.org/10.1139/cjz-2015-0128
  • Description: Photoperiodism involves the use of both absolute measures of day length and the direction in which day length is changing as a cue for regulating seasonal changes in physiology and behaviour so that birth and lactation coincide with optimal resource availability, increasing offspring survival. Induced ovulation and opportunistic breeding is often found in species that are predominantly solitary and territorial. In this study, the photoperiodic reproductive responses of male greater red musk shrews (Crocidura flavescens (I. Geoffroy Saint-Hilaire, 1827)) were investigated in the laboratory. The presence of spermatozoa regardless of the light cycle, suggest that although the shrews are photoresponsive, they may be capable of breeding throughout the year. Significantly greater testicular volume and eminiferous tubule diameter following exposure to a short day-light cycle suggests that these animals may have breeding peaks that correspond to short days. The presence of epidermal spines on the penis indicates that the shrew is likely also an induced ovulator. Flexible breeding patterns combined with induced ovulation affords this solitary species the greatest chance of reproductive success.
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  • Date Issued: 2016

The influence of photoperiod on the reproductive physiology of the greater red musk shrew: Crocidura flavescens

- Hoole, C, McKechnie, Andrew E, Parker, Daniel M, Bennett, Nigel C

  • Authors: Hoole, C , McKechnie, Andrew E , Parker, Daniel M , Bennett, Nigel C
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/70157 , vital:29626 , https://doi.org/10.1139/cjz-2015-0128
  • Description: Photoperiodism involves the use of both absolute measures of day length and the direction in which day length is changing as a cue for regulating seasonal changes in physiology and behaviour so that birth and lactation coincide with optimal resource availability, increasing offspring survival. Induced ovulation and opportunistic breeding is often found in species that are predominantly solitary and territorial. In this study, the photoperiodic reproductive responses of male greater red musk shrews (Crocidura flavescens (I. Geoffroy Saint-Hilaire, 1827)) were investigated in the laboratory. The presence of spermatozoa regardless of the light cycle, suggest that although the shrews are photoresponsive, they may be capable of breeding throughout the year. Significantly greater testicular volume and eminiferous tubule diameter following exposure to a short day-light cycle suggests that these animals may have breeding peaks that correspond to short days. The presence of epidermal spines on the penis indicates that the shrew is likely also an induced ovulator. Flexible breeding patterns combined with induced ovulation affords this solitary species the greatest chance of reproductive success.
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  • Date Issued: 2016

Aspects of the biology and life history of largespot pompano, Trachinotus botla, in South Africa

- Parker, Daniel M, Booth, Anthony J

  • Authors: Parker, Daniel M , Booth, Anthony J
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/123798 , vital:35499 , https://doi.10.1071/MF14029
  • Description: Trachinotus botla is an important recreational surf zone-dependent fish species distributed in the Indo-west Pacific from South Africa to Australia. In South Africa it is restricted to the northern KwaZulu-Natal coast. Biological investigations revealed that it is a fast growing species that attains a maximum age of, 7 years. Males and females sexually matured in their third year. It has a protracted summer spawning season with evidence of serial spawning behaviour. T. botla is an opportunistic predator with a generalist diet, with fish feeding on a wide variety of prey items particularly those that are temporally ‘superabundant’. Small fish fed predominantly on copepods and terrestrial insects, whereas larger fish consumed bivalves and crabs. Teleosts, primarily engraulids, were important components to the diet of fish of all sizes. An ontogenetic dietary shift was observed just after sexual maturity (300-mm fork length) that is possibly linked to a change in habitat preference with larger fish foraging on deeper reefs.
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  • Date Issued: 2015

Brown hyena habitat selection varies among sites in a semi-arid region of southern Africa

- Welch, Rebecca J, Tambling, Craig J, Bissett, Charlene, Gaylard, Angela, Müller, Konrad, Slater, Kerry, Strauss, W Maartin, Parker, Daniel M

  • Authors: Welch, Rebecca J , Tambling, Craig J , Bissett, Charlene , Gaylard, Angela , Müller, Konrad , Slater, Kerry , Strauss, W Maartin , Parker, Daniel M
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/123277 , vital:35423 , https://doi.10.1093/jmammal/gyv189
  • Description: In the last 50 years, the human impact on ecosystems has been greater than during any other time period in human history (Millennium Ecosystem Assessment 2003). Large carnivores face anthropogenic threats worldwide, specifically persecution, habitat degradation, and habitat fragmentation (Everatt et al. 2014; Groom et al. 2014; Ripple et al. 2014; Wolfe et al. 2015). Because large carnivores often occupy high trophic levels, their presence influences species at lower levels through trophic cascades (Ripple et al. 2014). Natural experiments, taking advantage of large carnivore management, have shown that large predators provide fundamental ecosystem and economic services that help maintain healthy and diverse ecosystems (Ripple et al. 2014). Additionally, carnivores play an important role in other ecosystem processes, for example, scavenging carnivores may provide regulatory services, such as waste removal, nutrient cycling, and disease regulation. Such services add stability to ecosystems and ensure energy flow through multiple trophic levels (DeVault et al. 2003; Wilson and Wolkovich 2011).
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  • Date Issued: 2015

Connectivity through allochthony: Reciprocal links between adjacent aquatic and terrestrial ecosystems in South Africa

- Richoux, Nicole B, Moyo, Sydney, Chari, Lenin D, Bergamino, Leandro, Carassou, Laure, Dalu, Tatenda, Hean, Jeffrey W, Sikutshwa, Likho, Gininda, Simphiwe, Magoro, Mandla L, Perhar, Gurbir, Ni, Felicity, Villet, Martin H, Whitfield, Alan K, Parker, Daniel M, Froneman, P William, Arhonditsis, George, Craig, Adrian J F K

  • Authors: Richoux, Nicole B , Moyo, Sydney , Chari, Lenin D , Bergamino, Leandro , Carassou, Laure , Dalu, Tatenda , Hean, Jeffrey W , Sikutshwa, Likho , Gininda, Simphiwe , Magoro, Mandla L , Perhar, Gurbir , Ni, Felicity , Villet, Martin H , Whitfield, Alan K , Parker, Daniel M , Froneman, P William , Arhonditsis, George , Craig, Adrian J F K
  • Date: 2015
  • Subjects: To be catalogued
  • Language: English
  • Type: text , report
  • Identifier: http://hdl.handle.net/10962/438363 , vital:73454 , ISBN 978-1-4312-0679-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2186-1-15.pdf
  • Description: An important aspect of the dynamics of nutrients and pollutants in natural systems is captured in the concept of allochthony, founded on the observation that nutrients and energy in a variety of forms are transferred between adjacent habitats, com-munities and ecosystems that are not routinely considered as connected. Different forms of nutrients and energy move across the conceptual boundaries of habitats via organisms’ activities or physical processes such as wind or water currents, and these transfers can represent important food subsidies. Such cross-partition ecolog-ical subsidies can augment the nutritional condition, biomass and biodiversity of communities, particularly where local production (or autochthony) alone may be inadequate to support local food webs. Furthermore, organic subsidies can influ-ence population dynamics, community interactions and ecosystem processes, and can represent dominant flux inputs in ecosystem budgets. Our intention was to ex-plore organic nutrient fluxes in relation to a primarily lotic (i.e. flowing) aquatic sys-tem at the scale of a hydrological catchment.
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  • Date Issued: 2015

Seasonal consumption of browse by the African buffalo (Syncerus caffer) in the Thicket Biome of South Africa

- Watermeyer, Jessica P, Carroll, Sarah L, Parker, Daniel M

  • Authors: Watermeyer, Jessica P , Carroll, Sarah L , Parker, Daniel M
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/126096 , vital:35849 , https://doi.org/10.1111/aje.12214
  • Description: The African buffalo (Syncerus caffer Sparrman) is both morphologically and physiologically adapted for grazing (Prins, 1996). However, buffalo populations of the Eastern Cape, South Africa, are confined to reserves dominated by thicket vegetation where grass is sparse (Landman & Kerley, 2001; Tshabalala, Dube & Lent, 2009). Given that the nutritional value of grass deteriorates more rapidly than browse in nonproductive periods (Shipley, 1993), it has been hypothesized that buffalo increase their intake of browse during the dry season (Tshabalala, Dube & Lent, 2009). However, past studies contradict one another (de Graaf, Schulz & van der Walt, 1973; Landman & Kerley, 2001; Tshabalala, Dube & Lent, 2009). de Graaf, Schulz & van der Walt (1973) analysed the rumen contents of buffalo in the Addo Elephant National Park and suggested that buffalo should be considered browsers because of the high proportion of browse in rumen samples. However, their study was restricted to one site during a drought. Landman & Kerley (2001) later found the opposite (grass comprised ~72% of buffalo dung) and criticized the findings of de Graaf, Schulz amp; van der Walt (1973). However, their study was conducted after a period of exceptionally high rainfall. More recently, Tshabalala, Dube & Lent (2009) recorded significantly more browse in the diet of buffalo during the dry season (33%) than the wet season (28%) at the Great Fish River Nature Reserve. We test the assertion that buffalo increase their intake of browse during dry periods, at another site dominated by thicket. We describe the extent to which grass and browse were consumed by buffalo and whether the proportional occurrence changed monthly.
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  • Date Issued: 2015

Elephants in Africa: Big, grey biodiversity thieves?

- Kuiper, Timothy R, Parker, Daniel M

  • Authors: Kuiper, Timothy R , Parker, Daniel M
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124385 , vital:35601 , https://doi.org/10.2989/16085914.2011.589120
  • Description: The conservation of biological diversity is one of the greatest challenges facing humanity today.1,2 Addressing this challenge must inevitably involve the maintenance of the composition, structure and functioning of multi-species ecosystems.2-4 While preventing the loss of particular species is an obvious strategy, a second goal might be to manage for local species diversity and the heterogeneity of habitats.5 A further objective may be the restoration of damaged ecosystems.6 Large herbivore assemblages form an important component of many diverse ecosystems and are of distinct ecological, and hence conservation, value.7-9 On the other hand, herbivores managed at unnaturally high densities may drive detrimental changes in the structural heterogeneity of habitats.10-12 Thus, decision-makers are faced with the challenge of balancing the needs of populations of large herbivores with the preservation of vegetation and ecosystem diversity.9 In light of these considerations, conclusions as to whether large herbivores are ‘good’ or ‘bad’ for biological diversity are both contentious and elusive. Nonetheless, we seek to explore this question with particular reference to African savannah elephants (Loxodonta africana). We discuss whether or not the elephant should be considered a biodiversity thief – a species that upsets the natural diversity of life in the habitat in which it lives.
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  • Date Issued: 2014
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